WIP: support rp2040

This was added in Go 1.18.

.circleci/config.yml

@@ -6,52 +6,6 @@ commands:
       - run:
           name: "Pull submodules"
           command: git submodule update --init
-  apt-dependencies:
-    parameters:
-      llvm:
-        type: string
-    steps:
-      - run:
-          name: "Install apt dependencies"
-          command: |
-            echo 'deb https://apt.llvm.org/buster/ llvm-toolchain-buster-<<parameters.llvm>> main' | sudo tee /etc/apt/sources.list.d/llvm.list
-            wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key|sudo apt-key add -
-            sudo apt-get update
-            sudo apt-get install \
-                llvm-<<parameters.llvm>>-dev \
-                clang-<<parameters.llvm>> \
-                libclang-<<parameters.llvm>>-dev \
-                lld-<<parameters.llvm>> \
-                gcc-arm-linux-gnueabihf \
-                gcc-aarch64-linux-gnu \
-                qemu-system-arm \
-                qemu-user \
-                gcc-avr \
-                avr-libc
-            sudo apt-get install --no-install-recommends libc6-dev-i386 lib32gcc-8-dev
-  install-node:
-    steps:
-      - run:
-          name: "Install node.js"
-          command: |
-            wget https://nodejs.org/dist/v10.15.1/node-v10.15.1-linux-x64.tar.xz
-            sudo tar -C /usr/local -xf node-v10.15.1-linux-x64.tar.xz
-            sudo ln -s /usr/local/node-v10.15.1-linux-x64/bin/node /usr/bin/node
-            rm node-v10.15.1-linux-x64.tar.xz
-  install-chrome:
-    steps:
-      - run:
-          name: "Install Chrome"
-          command: |
-            wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
-            sudo apt install ./google-chrome-stable_current_amd64.deb
-  install-wasmtime:
-    steps:
-      - run:
-          name: "Install wasmtime"
-          command: |
-            curl https://wasmtime.dev/install.sh -sSf | bash
-            sudo ln -s ~/.wasmtime/bin/wasmtime /usr/local/bin/wasmtime
   install-xtensa-toolchain:
     parameters:
       variant:
@@ -68,26 +22,38 @@ commands:
     steps:
       - restore_cache:
           keys:
-            - llvm-source-11-v1
+            - llvm-source-14-v2
       - run:
           name: "Fetch LLVM source"
           command: make llvm-source
       - save_cache:
-          key: llvm-source-11-v1
+          key: llvm-source-14-v2
           paths:
-            - llvm-project
-  build-wasi-libc:
+            - llvm-project/clang/lib/Headers
+            - llvm-project/clang/include
+            - llvm-project/compiler-rt
+            - llvm-project/lld/include
+            - llvm-project/llvm/include
+  hack-ninja-jobs:
+    steps:
+      - run:
+          name: "Hack Ninja to use less jobs"
+          command: |
+            echo -e '#!/bin/sh\n/usr/bin/ninja -j3 "$@"' > /go/bin/ninja
+            chmod +x /go/bin/ninja
+  build-binaryen-linux:
     steps:
       - restore_cache:
           keys:
-            - wasi-libc-sysroot-v4
+            - binaryen-linux-v1
       - run:
-          name: "Build wasi-libc"
-          command: make wasi-libc
+          name: "Build Binaryen"
+          command: |
+            make binaryen
       - save_cache:
-          key: wasi-libc-sysroot-v4
+          key: binaryen-linux-v1
           paths:
-            - lib/wasi-libc/sysroot
+            - build/wasm-opt
   test-linux:
     parameters:
       llvm:
@@ -95,11 +61,23 @@ commands:
     steps:
       - checkout
       - submodules
-      - apt-dependencies:
-          llvm: "<<parameters.llvm>>"
-      - install-node
-      - install-chrome
-      - install-wasmtime
+      - run:
+          name: "Install apt dependencies"
+          command: |
+            echo 'deb https://apt.llvm.org/buster/ llvm-toolchain-buster-<<parameters.llvm>> main' | sudo tee /etc/apt/sources.list.d/llvm.list
+            wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+            sudo apt-get update
+            sudo apt-get install --no-install-recommends \
+                llvm-<<parameters.llvm>>-dev \
+                clang-<<parameters.llvm>> \
+                libclang-<<parameters.llvm>>-dev \
+                lld-<<parameters.llvm>> \
+                gcc-avr \
+                avr-libc \
+                cmake \
+                ninja-build
+      - hack-ninja-jobs
+      - build-binaryen-linux
       - restore_cache:
           keys:
             - go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
@@ -108,293 +86,32 @@ commands:
       - run: go install -tags=llvm<<parameters.llvm>> .
       - restore_cache:
           keys:
-            - wasi-libc-sysroot-systemclang-v3
+            - wasi-libc-sysroot-systemclang-v5
       - run: make wasi-libc
       - save_cache:
-          key: wasi-libc-sysroot-systemclang-v3
+          key: wasi-libc-sysroot-systemclang-v5
           paths:
             - lib/wasi-libc/sysroot
-      - run: go test -v -tags=llvm<<parameters.llvm>> ./cgo ./compileopts ./compiler ./interp ./transform .
       - run: make gen-device -j4
       - run: make smoketest XTENSA=0
-      - run: make tinygo-test
-      - run: make wasmtest
       - save_cache:
           key: go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
           paths:
             - ~/.cache/go-build
             - /go/pkg/mod
       - run: make fmt-check
-  assert-test-linux:
-    steps:
-      - checkout
-      - submodules
-      - run:
-          name: "Install apt dependencies"
-          command: |
-            sudo apt-get update
-            sudo apt-get install \
-                gcc-arm-linux-gnueabihf \
-                libc6-dev-armel-cross \
-                gcc-aarch64-linux-gnu \
-                libc6-dev-arm64-cross \
-                qemu-system-arm \
-                qemu-user \
-                gcc-avr \
-                avr-libc
-            sudo apt-get install --no-install-recommends libc6-dev-i386 lib32gcc-6-dev
-      - install-node
-      - install-wasmtime
-      - install-xtensa-toolchain:
-          variant: "linux-amd64"
-      - restore_cache:
-          keys:
-            - go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
-            - go-cache-v2-{{ checksum "go.mod" }}
-      - llvm-source-linux
-      - restore_cache:
-          keys:
-            - llvm-build-11-linux-v2-assert
-      - run:
-          name: "Build LLVM"
-          command: |
-            if [ ! -f llvm-build/lib/liblldELF.a ]
-            then
-              # install dependencies
-              sudo apt-get install cmake ninja-build
-              # hack ninja to use less jobs
-              echo -e '#!/bin/sh\n/usr/bin/ninja -j3 "$@"' > /go/bin/ninja
-              chmod +x /go/bin/ninja
-              # build!
-              make ASSERT=1 llvm-build
-            fi
-      - save_cache:
-          key: llvm-build-11-linux-v2-assert
-          paths:
-            llvm-build
-      - run: |
-          # Note: -p=2 limits parallelism to two jobs at a time, which is
-          # necessary to keep memory consumption down and avoid OOM (for a
-          # 2CPU/4GB executor).
-          GOFLAGS="-p=2" make ASSERT=1
-      - build-wasi-libc
-      - run:
-          name: "Test TinyGo"
-          command: make ASSERT=1 test
-      - save_cache:
-          key: go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
-          paths:
-            - ~/.cache/go-build
-            - /go/pkg/mod
-      - run: make gen-device -j4
-      - run: make smoketest TINYGO=build/tinygo
-  build-linux:
-    steps:
-      - checkout
-      - submodules
-      - run:
-          name: "Install apt dependencies"
-          command: |
-            sudo apt-get update
-            sudo apt-get install \
-                gcc-arm-linux-gnueabihf \
-                libc6-dev-armel-cross \
-                gcc-aarch64-linux-gnu \
-                libc6-dev-arm64-cross \
-                qemu-system-arm \
-                qemu-user \
-                gcc-avr \
-                avr-libc
-            sudo apt-get install --no-install-recommends libc6-dev-i386 lib32gcc-6-dev
-      - install-node
-      - install-wasmtime
-      - install-xtensa-toolchain:
-          variant: "linux-amd64"
-      - restore_cache:
-          keys:
-            - go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
-            - go-cache-v2-{{ checksum "go.mod" }}
-      - llvm-source-linux
-      - restore_cache:
-          keys:
-            - llvm-build-11-linux-v2-noassert
-      - run:
-          name: "Build LLVM"
-          command: |
-            if [ ! -f llvm-build/lib/liblldELF.a ]
-            then
-              # install dependencies
-              sudo apt-get install cmake ninja-build
-              # hack ninja to use less jobs
-              echo -e '#!/bin/sh\n/usr/bin/ninja -j3 "$@"' > /go/bin/ninja
-              chmod +x /go/bin/ninja
-              # build!
-              make llvm-build
-            fi
-      - save_cache:
-          key: llvm-build-11-linux-v2-noassert
-          paths:
-            llvm-build
-      - build-wasi-libc
-      - run:
-          name: "Test TinyGo"
-          command: make test
-      - run:
-          name: "Install fpm"
-          command: |
-            sudo apt-get install ruby ruby-dev
-            sudo gem install --no-document fpm
-      - run:
-          name: "Build TinyGo release"
-          command: |
-            make release deb -j3
-            cp -p build/release.tar.gz /tmp/tinygo.linux-amd64.tar.gz
-            cp -p build/release.deb    /tmp/tinygo_amd64.deb
-      - store_artifacts:
-          path: /tmp/tinygo.linux-amd64.tar.gz
-      - store_artifacts:
-          path: /tmp/tinygo_amd64.deb
-      - save_cache:
-          key: go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
-          paths:
-            - ~/.cache/go-build
-            - /go/pkg/mod
-      - run:
-          name: "Extract release tarball"
-          command: |
-            mkdir -p ~/lib
-            tar -C ~/lib -xf /tmp/tinygo.linux-amd64.tar.gz
-            ln -s ~/lib/tinygo/bin/tinygo /go/bin/tinygo
-            tinygo version
-      - run: make smoketest
-  build-macos:
-    steps:
-      - checkout
-      - submodules
-      - run:
-          name: "Install dependencies"
-          command: |
-            curl https://dl.google.com/go/go1.16.darwin-amd64.tar.gz -o go1.16.darwin-amd64.tar.gz
-            sudo tar -C /usr/local -xzf go1.16.darwin-amd64.tar.gz
-            ln -s /usr/local/go/bin/go /usr/local/bin/go
-            HOMEBREW_NO_AUTO_UPDATE=1 brew install qemu
-      - install-xtensa-toolchain:
-          variant: "macos"
-      - restore_cache:
-          keys:
-            - go-cache-macos-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
-            - go-cache-macos-v2-{{ checksum "go.mod" }}
-      - restore_cache:
-          keys:
-            - llvm-source-11-macos-v1
-      - run:
-          name: "Fetch LLVM source"
-          command: make llvm-source
-      - save_cache:
-          key: llvm-source-11-macos-v1
-          paths:
-            - llvm-project
-      - restore_cache:
-          keys:
-            - llvm-build-11-macos-v2
-      - run:
-          name: "Build LLVM"
-          command: |
-            if [ ! -f llvm-build/lib/liblldELF.a ]
-            then
-              # install dependencies
-              HOMEBREW_NO_AUTO_UPDATE=1 brew install cmake ninja
-              # build!
-              make llvm-build
-            fi
-      - save_cache:
-          key: llvm-build-11-macos-v2
-          paths:
-            llvm-build
-      - restore_cache:
-          keys:
-            - wasi-libc-sysroot-macos-v3
-      - run:
-          name: "Build wasi-libc"
-          command: make wasi-libc
-      - save_cache:
-          key: wasi-libc-sysroot-macos-v3
-          paths:
-            - lib/wasi-libc/sysroot
-      - run:
-          name: "Test TinyGo"
-          command: make test
-      - run:
-          name: "Build TinyGo release"
-          command: |
-            make release -j3
-            cp -p build/release.tar.gz /tmp/tinygo.darwin-amd64.tar.gz
-      - store_artifacts:
-          path: /tmp/tinygo.darwin-amd64.tar.gz
-      - run:
-          name: "Extract release tarball"
-          command: |
-            mkdir -p ~/lib
-            tar -C /usr/local/opt -xf /tmp/tinygo.darwin-amd64.tar.gz
-            ln -s /usr/local/opt/tinygo/bin/tinygo /usr/local/bin/tinygo
-            tinygo version
-      - run: make smoketest AVR=0
-      - save_cache:
-          key: go-cache-macos-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
-          paths:
-            - ~/.cache/go-build
-            - /go/pkg/mod
 
 jobs:
-  test-llvm10-go113:
-    docker:
-      - image: circleci/golang:1.13-buster
-    steps:
-      - test-linux:
-          llvm: "10"
-  test-llvm10-go114:
-    docker:
-      - image: circleci/golang:1.14-buster
-    steps:
-      - test-linux:
-          llvm: "10"
-  test-llvm11-go115:
-    docker:
-      - image: circleci/golang:1.15-buster
-    steps:
-      - test-linux:
-          llvm: "11"
-  test-llvm11-go116:
+  test-llvm13-go116:
     docker:
       - image: circleci/golang:1.16-buster
     steps:
       - test-linux:
-          llvm: "11"
-  assert-test-linux:
-    docker:
-      - image: circleci/golang:1.14-stretch
-    steps:
-      - assert-test-linux
-  build-linux:
-    docker:
-      - image: circleci/golang:1.14-stretch
-    steps:
-      - build-linux
-  build-macos:
-    macos:
-      xcode: "10.1.0"
-    steps:
-      - build-macos
-
-
+          llvm: "13"
 
 workflows:
   test-all:
     jobs:
-      - test-llvm10-go113
-      - test-llvm10-go114
-      - test-llvm11-go115
-      - test-llvm11-go116
-      - build-linux
-      - build-macos
-      - assert-test-linux
+      # This tests our lowest supported versions of Go and LLVM, to make sure at
+      # least the smoke tests still pass.
+      - test-llvm13-go116

.dockerignore

@@ -0,0 +1,3 @@
+build/
+llvm-*/
+

.github/workflows/build-macos.yml

@@ -0,0 +1,98 @@
+name: macOS
+
+on:
+  pull_request:
+  push:
+    branches:
+      - dev
+      - release
+
+jobs:
+  build-macos:
+    name: build-macos
+    runs-on: macos-11
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Install Dependencies
+        shell: bash
+        run: |
+          HOMEBREW_NO_AUTO_UPDATE=1 brew install qemu binaryen
+      - name: Install Xtensa toolchain
+        shell: bash
+        run: |
+          curl -L https://github.com/espressif/crosstool-NG/releases/download/esp-2020r2/xtensa-esp32-elf-gcc8_2_0-esp-2020r2-macos.tar.gz -o xtensa-esp32-elf-gcc8_2_0-esp-2020r2-macos.tar.gz
+          sudo tar -C /usr/local -xf xtensa-esp32-elf-gcc8_2_0-esp-2020r2-macos.tar.gz
+          sudo ln -s /usr/local/xtensa-esp32-elf/bin/xtensa-esp32-elf-ld /usr/local/bin/xtensa-esp32-elf-ld
+          rm xtensa-esp32-elf-gcc8_2_0-esp-2020r2-macos.tar.gz
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-macos-v1
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-macos-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        shell: bash
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # install dependencies
+          HOMEBREW_NO_AUTO_UPDATE=1 brew install cmake ninja
+          # build!
+          make llvm-build
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache wasi-libc sysroot
+        uses: actions/cache@v2
+        id: cache-wasi-libc
+        with:
+          key: wasi-libc-sysroot-v3
+          path: lib/wasi-libc/sysroot
+      - name: Build wasi-libc
+        if: steps.cache-wasi-libc.outputs.cache-hit != 'true'
+        run: make wasi-libc
+      - name: Test TinyGo
+        shell: bash
+        run: make test GOTESTFLAGS="-v -short"
+      - name: Build TinyGo release tarball
+        run: make release -j3
+      - name: Test stdlib packages
+        run: make tinygo-test
+      - name: Make release artifact
+        shell: bash
+        run: cp -p build/release.tar.gz build/tinygo.darwin-amd64.tar.gz 
+      - name: Publish release artifact
+        # Note: this release artifact is double-zipped, see:
+        # https://github.com/actions/upload-artifact/issues/39
+        # We can essentially pick one of these:
+        # - have a double-zipped artifact when downloaded from the UI
+        # - have a very slow artifact upload
+        # We're doing the former here, to keep artifact uploads fast.
+        uses: actions/upload-artifact@v2
+        with:
+          name: release-double-zipped
+          path: build/tinygo.darwin-amd64.tar.gz
+      - name: Smoke tests
+        shell: bash
+        run: make smoketest TINYGO=$(PWD)/build/tinygo AVR=0

.github/workflows/docker.yml

@@ -0,0 +1,83 @@
+# This is the Github action to build and push the tinygo/tinygo-dev Docker image.
+# If you are looking for the tinygo/tinygo "release" Docker image please see
+# https://github.com/tinygo-org/docker
+#
+name: Docker
+on:
+  push:
+    branches: [ dev, fix-docker-llvm-build ]
+
+jobs:
+  push_to_registry:
+    name: build-push-dev
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v2
+        with:
+          submodules: recursive
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: |
+            tinygo/tinygo-dev
+            ghcr.io/${{ github.repository }}/tinygo-dev
+          tags: |
+            type=sha,format=long
+            type=raw,value=latest
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
+      - name: Log in to Github Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
+      - name: Trigger Drivers repo build on CircleCI
+        run: |
+          curl --location --request POST 'https://circleci.com/api/v2/project/github/tinygo-org/drivers/pipeline' \
+            --header 'Content-Type: application/json' \
+            -d '{"branch": "dev"}' \
+            -u "${{ secrets.CIRCLECI_API_TOKEN }}"
+      - name: Trigger Bluetooth repo build on CircleCI
+        run: |
+          curl --location --request POST 'https://circleci.com/api/v2/project/github/tinygo-org/bluetooth/pipeline' \
+            --header 'Content-Type: application/json' \
+            -d '{"branch": "dev"}' \
+            -u "${{ secrets.CIRCLECI_API_TOKEN }}"
+      - name: Trigger TinyFS repo build on CircleCI
+        run: |
+          curl --location --request POST 'https://circleci.com/api/v2/project/github/tinygo-org/tinyfs/pipeline' \
+            --header 'Content-Type: application/json' \
+            -d '{"branch": "dev"}' \
+            -u "${{ secrets.CIRCLECI_API_TOKEN }}"
+      - name: Trigger TinyFont repo build on CircleCI
+        run: |
+          curl --location --request POST 'https://circleci.com/api/v2/project/github/tinygo-org/tinyfont/pipeline' \
+            --header 'Content-Type: application/json' \
+            -d '{"branch": "dev"}' \
+            -u "${{ secrets.CIRCLECI_API_TOKEN }}"
+      - name: Trigger TinyDraw repo build on CircleCI
+        run: |
+          curl --location --request POST 'https://circleci.com/api/v2/project/github/tinygo-org/tinydraw/pipeline' \
+            --header 'Content-Type: application/json' \
+            -d '{"branch": "dev"}' \
+            -u "${{ secrets.CIRCLECI_API_TOKEN }}"

.github/workflows/linux.yml

@@ -0,0 +1,448 @@
+name: Linux
+
+on:
+  pull_request:
+  push:
+    branches:
+      - dev
+      - release
+
+jobs:
+  build-linux:
+    # Build Linux binaries, ready for release.
+    # This intentionally uses an older Linux image, so that we compile against
+    # an older glibc version and therefore are compatible with a wide range of
+    # Linux distributions.
+    runs-on: ubuntu-18.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Install apt dependencies
+        run: |
+          sudo apt-get install --no-install-recommends \
+              ninja-build
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Cache Go
+        uses: actions/cache@v2
+        with:
+          key: go-cache-linux-v1-${{ hashFiles('go.mod') }}
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-linux-v2
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-linux-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # build!
+          make llvm-build
+          # Remove unnecessary object files (to reduce cache size).
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache Binaryen
+        uses: actions/cache@v2
+        id: cache-binaryen
+        with:
+          key: binaryen-linux-v1
+          path: build/wasm-opt
+      - name: Build Binaryen
+        if: steps.cache-binaryen.outputs.cache-hit != 'true'
+        run: make binaryen
+      - name: Cache wasi-libc
+        uses: actions/cache@v2
+        id: cache-wasi-libc
+        with:
+          key: wasi-libc-sysroot-linux-asserts-v4
+          path: lib/wasi-libc/sysroot
+      - name: Build wasi-libc
+        if: steps.cache-wasi-libc.outputs.cache-hit != 'true'
+        run: make wasi-libc
+      - name: Install fpm
+        run: |
+          sudo gem install --no-document fpm
+      - name: Build TinyGo release
+        run: |
+          make release deb -j3
+          cp -p build/release.tar.gz /tmp/tinygo.linux-amd64.tar.gz
+          cp -p build/release.deb    /tmp/tinygo_amd64.deb
+      - name: Publish release artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: linux-amd64-double-zipped
+          path: |
+            /tmp/tinygo.linux-amd64.tar.gz
+            /tmp/tinygo_amd64.deb
+  test-linux-build:
+    # Test the binaries built in the build-linux job by running the smoke tests.
+    runs-on: ubuntu-latest
+    needs: build-linux
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Install wasmtime
+        run: |
+          curl https://wasmtime.dev/install.sh -sSf | bash
+          echo "$HOME/.wasmtime/bin" >> $GITHUB_PATH
+      - name: Download release artifact
+        uses: actions/download-artifact@v2
+        with:
+          name: linux-amd64-double-zipped
+      - name: Extract release tarball
+        run: |
+          mkdir -p ~/lib
+          tar -C ~/lib -xf tinygo.linux-amd64.tar.gz
+          ln -s ~/lib/tinygo/bin/tinygo ~/go/bin/tinygo
+      - name: Install apt dependencies
+        run: |
+          sudo apt-get install --no-install-recommends \
+              gcc-avr \
+              avr-libc
+      - name: "Install Xtensa toolchain"
+        run: |
+          curl -L https://github.com/espressif/crosstool-NG/releases/download/esp-2020r2/xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz -o xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+          sudo tar -C /usr/local -xf xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+          sudo ln -s /usr/local/xtensa-esp32-elf/bin/xtensa-esp32-elf-ld /usr/local/bin/xtensa-esp32-elf-ld
+          rm xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+      - run: make tinygo-test-wasi-fast
+      - run: make smoketest
+  assert-test-linux:
+    # Run all tests that can run on Linux, with LLVM assertions enabled to catch
+    # potential bugs.
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Install apt dependencies
+        run: |
+          echo "Show cpuinfo; sometimes useful when troubleshooting"
+          cat /proc/cpuinfo
+          sudo apt-get update
+          sudo apt-get install --no-install-recommends \
+              qemu-system-arm \
+              qemu-system-riscv32 \
+              qemu-user \
+              gcc-avr \
+              avr-libc \
+              simavr \
+              ninja-build
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Install Node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: '12'
+      - name: Install wasmtime
+        run: |
+          curl https://wasmtime.dev/install.sh -sSf | bash
+          echo "$HOME/.wasmtime/bin" >> $GITHUB_PATH
+      - name: Cache Go
+        uses: actions/cache@v2
+        with:
+          key: go-cache-linux-asserts-v1-${{ hashFiles('go.mod') }}
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-linux-asserts-v2
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-linux-asserts-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # build!
+          make llvm-build ASSERT=1
+          # Remove unnecessary object files (to reduce cache size).
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache Binaryen
+        uses: actions/cache@v2
+        id: cache-binaryen
+        with:
+          key: binaryen-linux-asserts-v1
+          path: build/wasm-opt
+      - name: Build Binaryen
+        if: steps.cache-binaryen.outputs.cache-hit != 'true'
+        run: make binaryen
+      - name: Cache wasi-libc
+        uses: actions/cache@v2
+        id: cache-wasi-libc
+        with:
+          key: wasi-libc-sysroot-linux-asserts-v4
+          path: lib/wasi-libc/sysroot
+      - name: Build wasi-libc
+        if: steps.cache-wasi-libc.outputs.cache-hit != 'true'
+        run: make wasi-libc
+      - run: make gen-device -j4
+      - name: Test TinyGo
+        run: make ASSERT=1 test
+      - name: Build TinyGo
+        run: |
+          make ASSERT=1
+          echo "$(pwd)/build" >> $GITHUB_PATH
+      - name: Test stdlib packages
+        run: make tinygo-test
+      - name: Install Xtensa toolchain
+        run: |
+          curl -L https://github.com/espressif/crosstool-NG/releases/download/esp-2020r2/xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz -o xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+          sudo tar -C /usr/local -xf xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+          sudo ln -s /usr/local/xtensa-esp32-elf/bin/xtensa-esp32-elf-ld /usr/local/bin/xtensa-esp32-elf-ld
+          rm xtensa-esp32-elf-gcc8_2_0-esp-2020r2-linux-amd64.tar.gz
+      - run: make smoketest
+      - run: make wasmtest
+      - run: make tinygo-baremetal
+  build-linux-arm:
+    # Build ARM Linux binaries, ready for release.
+    # This intentionally uses an older Linux image, so that we compile against
+    # an older glibc version and therefore are compatible with a wide range of
+    # Linux distributions.
+    # It is set to "needs: build-linux" because it modifies the release created
+    # in that process to avoid doing lots of duplicate work and to avoid
+    # complications around precompiled libraries such as compiler-rt shipped as
+    # part of the release tarball.
+    runs-on: ubuntu-18.04
+    needs: build-linux
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install apt dependencies
+        run: |
+          sudo apt-get install --no-install-recommends \
+              qemu-user \
+              g++-arm-linux-gnueabihf \
+              libc6-dev-armhf-cross
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Cache Go
+        uses: actions/cache@v2
+        with:
+          key: go-cache-linux-arm-v2-${{ hashFiles('go.mod') }}
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-linux-v2
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-linux-arm-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # Install build dependencies.
+          sudo apt-get install --no-install-recommends ninja-build
+          # build!
+          make llvm-build CROSS=arm-linux-gnueabihf
+          # Remove unnecessary object files (to reduce cache size).
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache Binaryen
+        uses: actions/cache@v2
+        id: cache-binaryen
+        with:
+          key: binaryen-linux-arm-v1
+          path: build/wasm-opt
+      - name: Build Binaryen
+        if: steps.cache-binaryen.outputs.cache-hit != 'true'
+        run: |
+          sudo apt-get install --no-install-recommends ninja-build
+          git submodule update --init lib/binaryen
+          make CROSS=arm-linux-gnueabihf binaryen
+      - name: Install fpm
+        run: |
+          sudo gem install --no-document fpm
+      - name: Build TinyGo binary
+        run: |
+          make CROSS=arm-linux-gnueabihf
+      - name: Download amd64 release
+        uses: actions/download-artifact@v2
+        with:
+          name: linux-amd64-double-zipped
+      - name: Extract amd64 release
+        run: |
+          mkdir -p build/release
+          tar -xf tinygo.linux-amd64.tar.gz -C build/release tinygo
+      - name: Modify release
+        run: |
+          cp -p build/tinygo   build/release/tinygo/bin
+          cp -p build/wasm-opt build/release/tinygo/bin
+      - name: Create arm release
+        run: |
+          make release deb RELEASEONLY=1 DEB_ARCH=armhf
+          cp -p build/release.tar.gz /tmp/tinygo.linux-arm.tar.gz
+          cp -p build/release.deb    /tmp/tinygo_armhf.deb
+      - name: Publish release artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: linux-arm-double-zipped
+          path: |
+            /tmp/tinygo.linux-arm.tar.gz
+            /tmp/tinygo_armhf.deb
+  build-linux-arm64:
+    # Build ARM64 Linux binaries, ready for release.
+    # It is set to "needs: build-linux" because it modifies the release created
+    # in that process to avoid doing lots of duplicate work and to avoid
+    # complications around precompiled libraries such as compiler-rt shipped as
+    # part of the release tarball.
+    runs-on: ubuntu-18.04
+    needs: build-linux
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install apt dependencies
+        run: |
+          sudo apt-get install --no-install-recommends \
+              qemu-user \
+              g++-aarch64-linux-gnu \
+              libc6-dev-arm64-cross \
+              ninja-build
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - name: Cache Go
+        uses: actions/cache@v2
+        with:
+          key: go-cache-linux-arm64-v2-${{ hashFiles('go.mod') }}
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-linux-v1
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-linux-arm64-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # build!
+          make llvm-build CROSS=aarch64-linux-gnu
+          # Remove unnecessary object files (to reduce cache size).
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache Binaryen
+        uses: actions/cache@v2
+        id: cache-binaryen
+        with:
+          key: binaryen-linux-arm64-v1
+          path: build/wasm-opt
+      - name: Build Binaryen
+        if: steps.cache-binaryen.outputs.cache-hit != 'true'
+        run: |
+          git submodule update --init lib/binaryen
+          make CROSS=aarch64-linux-gnu binaryen
+      - name: Install fpm
+        run: |
+          sudo gem install --no-document fpm
+      - name: Build TinyGo binary
+        run: |
+          make CROSS=aarch64-linux-gnu
+      - name: Download amd64 release
+        uses: actions/download-artifact@v2
+        with:
+          name: linux-amd64-double-zipped
+      - name: Extract amd64 release
+        run: |
+          mkdir -p build/release
+          tar -xf tinygo.linux-amd64.tar.gz -C build/release tinygo
+      - name: Modify release
+        run: |
+          cp -p build/tinygo   build/release/tinygo/bin
+          cp -p build/wasm-opt build/release/tinygo/bin
+      - name: Create arm64 release
+        run: |
+          make release deb RELEASEONLY=1 DEB_ARCH=arm64
+          cp -p build/release.tar.gz /tmp/tinygo.linux-arm64.tar.gz
+          cp -p build/release.deb    /tmp/tinygo_arm64.deb
+      - name: Publish release artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: linux-arm64-double-zipped
+          path: |
+            /tmp/tinygo.linux-arm64.tar.gz
+            /tmp/tinygo_arm64.deb

.github/workflows/windows.yml

@@ -0,0 +1,105 @@
+name: Windows
+
+on:
+  pull_request:
+  push:
+    branches:
+      - dev
+      - release
+
+jobs:
+  build-windows:
+    runs-on: windows-2022
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.1'
+      - uses: brechtm/setup-scoop@v2
+        with:
+          scoop_update: 'false'
+      - name: Install Dependencies
+        shell: bash
+        run: |
+          scoop install ninja binaryen
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Cache Go
+        uses: actions/cache@v2
+        with:
+          key: go-cache-windows-v1-${{ hashFiles('go.mod') }}
+          path: |
+            ~/AppData/Local/go-build
+            ~/go/pkg/mod
+      - name: Cache LLVM source
+        uses: actions/cache@v2
+        id: cache-llvm-source
+        with:
+          key: llvm-source-14-windows-v2
+          path: |
+            llvm-project/clang/lib/Headers
+            llvm-project/clang/include
+            llvm-project/compiler-rt
+            llvm-project/lld/include
+            llvm-project/llvm/include
+      - name: Download LLVM source
+        if: steps.cache-llvm-source.outputs.cache-hit != 'true'
+        run: make llvm-source
+      - name: Cache LLVM build
+        uses: actions/cache@v2
+        id: cache-llvm-build
+        with:
+          key: llvm-build-14-windows-v1
+          path: llvm-build
+      - name: Build LLVM
+        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
+        shell: bash
+        run: |
+          # fetch LLVM source
+          rm -rf llvm-project
+          make llvm-source
+          # build!
+          make llvm-build
+          # Remove unnecessary object files (to reduce cache size).
+          find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
+      - name: Cache wasi-libc sysroot
+        uses: actions/cache@v2
+        id: cache-wasi-libc
+        with:
+          key: wasi-libc-sysroot-v3
+          path: lib/wasi-libc/sysroot
+      - name: Build wasi-libc
+        if: steps.cache-wasi-libc.outputs.cache-hit != 'true'
+        run: make wasi-libc
+      - name: Install wasmtime
+        run: |
+          scoop install wasmtime
+      - name: Test TinyGo
+        shell: bash
+        run: make test GOTESTFLAGS="-v -short"
+      - name: Build TinyGo release tarball
+        run: make build/release -j4
+      - name: Make release artifact
+        shell: bash
+        working-directory: build/release
+        run: 7z -tzip a release.zip tinygo
+      - name: Publish release artifact
+        # Note: this release artifact is double-zipped, see:
+        # https://github.com/actions/upload-artifact/issues/39
+        # We can essentially pick one of these:
+        # - have a dobule-zipped artifact when downloaded from the UI
+        # - have a very slow artifact upload
+        # We're doing the former here, to keep artifact uploads fast.
+        uses: actions/upload-artifact@v2
+        with:
+          name: release-double-zipped
+          path: build/release/release.zip
+      - name: Smoke tests
+        shell: bash
+        run: make smoketest TINYGO=$(PWD)/build/tinygo AVR=0 XTENSA=0
+      - name: Test stdlib packages
+        run: make tinygo-test
+      - name: Test stdlib packages on wasi
+        run: make tinygo-test-wasi-fast

.gitignore

@@ -1,4 +1,3 @@
-build
 docs/_build
 src/device/avr/*.go
 src/device/avr/*.ld
@@ -16,11 +15,17 @@ src/device/stm32/*.go
 src/device/stm32/*.s
 src/device/kendryte/*.go
 src/device/kendryte/*.s
+src/device/rp/*.go
+src/device/rp/*.s
 vendor
 llvm-build
 llvm-project
+build/*
 
 # Ignore files generated by smoketest
+test.bin
+test.elf
+test.exe
 test.gba
 test.hex
 test.nro

.gitmodules

@@ -10,10 +10,6 @@
 [submodule "lib/cmsis-svd"]
 	path = lib/cmsis-svd
 	url = https://github.com/tinygo-org/cmsis-svd
-[submodule "lib/compiler-rt"]
-	path = lib/compiler-rt
-	url = https://github.com/llvm-mirror/compiler-rt.git
-	branch = release_80
 [submodule "lib/wasi-libc"]
 	path = lib/wasi-libc
 	url = https://github.com/CraneStation/wasi-libc
@@ -23,3 +19,15 @@
 [submodule "lib/stm32-svd"]
 	path = lib/stm32-svd
 	url = https://github.com/tinygo-org/stm32-svd
+[submodule "lib/musl"]
+	path = lib/musl
+	url = git://git.musl-libc.org/musl
+[submodule "lib/binaryen"]
+	path = lib/binaryen
+	url = https://github.com/WebAssembly/binaryen.git
+[submodule "lib/mingw-w64"]
+	path = lib/mingw-w64
+	url = https://github.com/mingw-w64/mingw-w64.git
+[submodule "lib/macos-minimal-sdk"]
+	path = lib/macos-minimal-sdk
+	url = https://github.com/aykevl/macos-minimal-sdk.git

BUILDING.md

@@ -11,19 +11,14 @@ lld so that the binary can be easily moved between systems. It also shows how to
 build a release tarball that includes this binary and all necessary extra files.
 
 **Note**: this documentation describes how to build a statically linked release
-tarball. If you want to develop TinyGo, you will probably want to follow a
-different guide:
-
-  * [Linux](https://tinygo.org/getting-started/linux/#source-install)
-  * [macOS](https://tinygo.org/getting-started/macos/#source-install)
-  * [Windows](https://tinygo.org/getting-started/windows/#source-install)
+tarball. If you want to help with development of TinyGo itself, you should follow the guide located at https://tinygo.org/docs/guides/build/
 
 ## Dependencies
 
 LLVM, Clang and LLD are quite light on dependencies, requiring only standard
 build tools to be built. Go is of course necessary to build TinyGo itself.
 
-  * Go (1.13+)
+  * Go (1.16+)
   * Standard build tools (gcc/clang)
   * git
   * CMake

CHANGELOG.md

@@ -1,3 +1,558 @@
+0.23.0
+---
+
+* **command line**
+  - add `-work` flag
+  - add Go 1.18 support
+  - add LLVM 14 support
+  - `run`: add support for command-line parameters
+  - `build`: calculate default output path if `-o` is not specified
+  - `build`: add JSON output
+  - `test`: support multiple test binaries with `-c`
+  - `test`: support flags like `-v` on all targets (including emulated firmware)
+* **compiler**
+  - add support for ThinLTO
+  - use compiler-rt from LLVM
+  - `builder`: prefer GNU build ID over Go build ID for caching
+  - `builder`: add support for cross compiling to Darwin
+  - `builder`: support machine outlining pass in stacksize calculation
+  - `builder`: disable asynchronous unwind tables
+  - `compileopts`: fix emulator configuration on non-amd64 Linux architectures
+  - `compiler`: move allocations > 256  bytes to the heap
+  - `compiler`: fix incorrect `unsafe.Alignof` on some 32-bit architectures
+  - `compiler`: accept alias for slice `cap` builtin
+  - `compiler`: allow slices of empty structs
+  - `compiler`: fix difference in aliases in interface methods
+  - `compiler`: make `RawSyscall` an alias for `Syscall`
+  - `compiler`: remove support for memory references in `AsmFull`
+  - `loader`: only add Clang header path for CGo
+  - `transform`: fix poison value in heap-to-stack transform
+* **standard library**
+  - `internal/fuzz`: add this package as a shim
+  - `os`: implement readdir for darwin and linux
+  - `os`: add `DirFS`, which is used by many programs to access readdir.
+  - `os`: isWine: be compatible with older versions of wine, too
+  - `os`: implement `RemoveAll`
+  - `os`: Use a `uintptr` for `NewFile`
+  - `os`: add stubs for `exec.ExitError` and `ProcessState.ExitCode`
+  - `os`: export correct values for `DevNull` for each OS
+  - `os`: improve support for `Signal` by fixing various bugs
+  - `os`: implement `File.Fd` method
+  - `os`: implement `UserHomeDir`
+  - `os`: add `exec.ProcessState` stub
+  - `os`: implement `Pipe` for darwin
+  - `os`: define stub `ErrDeadlineExceeded`
+  - `reflect`: add stubs for more missing methods
+  - `reflect`: rename `reflect.Ptr` to `reflect.Pointer`
+  - `reflect`: add `Value.FieldByIndexErr` stub
+  - `runtime`: fix various small GC bugs
+  - `runtime`: use memzero for leaking collector instead of manually zeroing objects
+  - `runtime`: implement `memhash`
+  - `runtime`: implement `fastrand`
+  - `runtime`: add stub for `debug.ReadBuildInfo`
+  - `runtime`: add stub for `NumCPU`
+  - `runtime`: don't inline `runtime.alloc` with `-gc=leaking`
+  - `runtime`: add `Version`
+  - `runtime`: add stubs for `NumCgoCall` and `NumGoroutine`
+  - `runtime`: stub {Lock,Unlock}OSThread on Windows
+  - `runtime`: be able to deal with a very small heap
+  - `syscall`: make `Environ` return a copy of the environment
+  - `syscall`: implement getpagesize and munmap
+  - `syscall`: `wasi`: define `MAP_SHARED` and `PROT_READ`
+  - `syscall`: stub mmap(), munmap(), MAP_SHARED, PROT_READ, SIGBUS, etc. on nonhosted targets
+  - `syscall`: darwin: more complete list of signals
+  - `syscall`: `wasi`: more complete list of signals
+  - `syscall`: stub `WaitStatus`
+  - `syscall/js`: allow copyBytesTo(Go|JS) to use `Uint8ClampedArray`
+  - `testing`: implement `TempDir`
+  - `testing`: nudge type TB closer to upstream; should be a no-op change.
+  - `testing`: on baremetal platforms, use simpler test matcher
+* **targets**
+  - `atsamd`: fix usbcdc initialization when `-serial=uart`
+  - `atsamd51`: allow higher frequency when using SPI
+  - `esp`: support CGo
+  - `esp32c3`: add support for input pin
+  - `esp32c3`: add support for GPIO interrupts
+  - `esp32c3`: add support to receive UART data
+  - `rp2040`: fix PWM bug at high frequency
+  - `rp2040`: fix some minor I2C bugs
+  - `rp2040`: fix incorrect inline assembly
+  - `rp2040`: fix spurious i2c STOP during write+read transaction
+  - `rp2040`: improve ADC support
+  - `wasi`: remove `--export-dynamic` linker flag
+  - `wasm`: remove heap allocator from wasi-libc
+* **boards**
+  - `circuitplay-bluefruit`: move pin mappings so board can be compiled for WASM use in Playground
+  - `esp32-c3-12f`: add the ESP32-C3-12f Kit
+  - `m5stamp-c3`: add pin setting of UART
+  - `macropad-rp2040`: add the Adafruit MacroPad RP2040 board
+  - `nano-33-ble`: typo in LPS22HB peripheral definition and documentation (#2579)
+  - `teensy41`: add the Teensy 4.1 board
+  - `teensy40`: add ADC support
+  - `teensy40`: add SPI support
+  - `thingplus-rp2040`: add the SparkFun Thing Plus RP2040 board
+  - `wioterminal`: add DefaultUART
+  - `wioterminal`: verify written data when flashing through OpenOCD
+  - `xiao-ble`: add XIAO BLE nRF52840 support
+
+
+0.22.0
+---
+
+* **command line**
+  - add asyncify to scheduler flag help
+  - support -run for tests
+  - remove FreeBSD target support
+  - add LLVM 12 and LLVM 13 support, use LLVM 13 by default
+  - add support for ARM64 MacOS
+  - improve help
+  - check /run/media as well as /media on Linux for non-debian-based distros
+  - `test`: set cmd.Dir even when running emulators
+  - `info`: add JSON output using the `-json` flag
+* **compiler**
+  - `builder`: fix off-by-one in size calculation
+  - `builder`: handle concurrent library header rename
+  - `builder`: use flock to avoid double-compiles
+  - `builder`: use build ID as cache key
+  - `builder`: add -fno-stack-protector to musl build
+  - `builder`: update clang header search path to look in /usr/lib
+  - `builder`: explicitly disable unwind tables for ARM
+  - `cgo`: add support for `C.CString` and related functions
+  - `compiler`: fix ranging over maps with particular map types
+  - `compiler`: add correct debug location to init instructions
+  - `compiler`: fix emission of large object layouts
+  - `compiler`: work around AVR atomics bugs
+  - `compiler`: predeclare runtime.trackPointer
+  - `interp`: work around AVR function pointers in globals
+  - `interp`: run goroutine starts and checks at runtime
+  - `interp`: always run atomic and volatile loads/stores at runtime
+  - `interp`: bump timeout to 180 seconds
+  - `interp`: handle type assertions on nil interfaces
+  - `loader`: elminate goroot cache inconsistency
+  - `loader`: respect $GOROOT when running `go list`
+  - `transform`: allocate the correct amount of bytes in an alloca
+  - `transform`: remove switched func lowering
+* **standard library**
+  - `crypto/rand`: show error if platform has no rng
+  - `device/*`: add `*_Msk` field for each bit field and avoid duplicates
+  - `device/*`: provide Set/Get for each register field described in the SVD files
+  - `internal/task`: swap stack chain when switching goroutines
+  - `internal/task`: remove `-scheduler=coroutines`
+  - `machine`: add `Device` string constant
+  - `net`: add bare Interface implementation
+  - `net`: add net.Buffers
+  - `os`: stub out support for some features
+  - `os`: obey TMPDIR on unix, TMP on Windows, etc
+  - `os`: implement `ReadAt`, `Mkdir`, `Remove`, `Stat`, `Lstat`, `CreateTemp`, `MkdirAll`, `Chdir`, `Chmod`, `Clearenv`, `Unsetenv`, `Setenv`, `MkdirTemp`, `Rename`, `Seek`, `ExpandEnv`, `Symlink`, `Readlink`
+  - `os`: implement `File.Stat`
+  - `os`: fix `IsNotExist` on nonexistent path
+  - `os`: fix opening files on WASI in read-only mode
+  - `os`: work around lack of `syscall.seek` on 386 and arm
+  - `reflect`: make sure indirect pointers are handled correctly
+  - `runtime`: allow comparing interfaces
+  - `runtime`: use LLVM intrinsic to read the stack pointer
+  - `runtime`: strengthen hashmap hash function for structs and arrays
+  - `runtime`: fix float/complex hashing
+  - `runtime`: fix nil map dereference
+  - `runtime`: add realloc implementation to GCs
+  - `runtime`: handle negative sleep times
+  - `runtime`: correct GC scan bounds
+  - `runtime`: remove extalloc GC
+  - `rumtime`: implement `__sync` libcalls as critical sections for most microcontrollers
+  - `runtime`: add stubs for `Func.FileLine` and `Frame.PC`
+  - `sync`: fix concurrent read-lock on write-locked RWMutex
+  - `sync`: add a package doc
+  - `sync`: add tests
+  - `syscall`: add support for `Mmap` and `Mprotect`
+  - `syscall`: fix array size for mmap slice creation
+  - `syscall`: enable `Getwd` in wasi
+  - `testing`: add a stub for `CoverMode`
+  - `testing`: support -bench option to run benchmarks matching the given pattern.
+  - `testing`: support b.SetBytes(); implement sub-benchmarks.
+  - `testing`: replace spaces with underscores in test/benchmark names, as upstream does
+  - `testing`: implement testing.Cleanup
+  - `testing`: allow filtering subbenchmarks with the `-bench` flag
+  - `testing`: implement `-benchtime` flag
+  - `testing`: print duration
+  - `testing`: allow filtering of subtests using `-run`
+* **targets**
+  - `all`: change LLVM features to match vanilla Clang
+  - `avr`: use interrupt-based timer which is much more accurate
+  - `nrf`: fix races in I2C
+  - `samd51`: implement TRNG for randomness
+  - `stm32`: pull-up on I2C lines
+  - `stm32`: fix timeout for i2c comms
+  - `stm32f4`, `stm32f103`: initial implementation for ADC
+  - `stm32f4`, `stm32f7`, `stm32l0x2`, `stm32l4`, `stm32l5`, `stm32wl`: TRNG implementation in crypto/rand
+  - `stm32wl`: add I2C support
+  - `windows`: add support for the `-size=` flag
+  - `wasm`: add support for `tinygo test`
+  - `wasi`, `wasm`: raise default stack size to 16 KiB
+* **boards**
+  - add M5Stack
+  - add lorae5 (stm32wle) support
+  - add Generic Node Sensor Edition
+  - add STM32F469 Discovery
+  - add M5Stamp C3
+  - add Blues Wireless Swan
+  - `bluepill`: add definitions for ADC pins
+  - `stm32f4disco`: add definitions for ADC pins
+  - `stm32l552ze`: use supported stlink interface
+  - `microbit-v2`: add some pin definitions
+
+
+0.21.0
+---
+
+* **command line**
+  - drop support for LLVM 10
+  - `build`: drop support for LLVM targets in the -target flag
+  - `build`: fix paths in error messages on Windows
+  - `build`: add -p flag to set parallelism
+  - `lldb`: implement `tinygo lldb` subcommand
+  - `test`: use emulator exit code instead of parsing test output
+  - `test`: pass testing arguments to wasmtime
+* **compiler**
+  - use -opt flag for optimization level in CFlags (-Os, etc)
+  - `builder`: improve accuracy of the -size=full flag
+  - `builder`: hardcode some more frame sizes for __aeabi_* functions
+  - `builder`: add support for -size= flag for WebAssembly
+  - `cgo`: fix line/column reporting in syntax error messages
+  - `cgo`: support function definitions in CGo headers
+  - `cgo`: implement rudimentary C array decaying
+  - `cgo`: add support for stdio in picolibc and wasi-libc
+  - `cgo`: run CGo parser per file, not per CGo fragment
+  - `compiler`: fix unintentionally exported math functions
+  - `compiler`: properly implement div and rem operations
+  - `compiler`: add support for recursive function types
+  - `compiler`: add support for the `go` keyword on interface methods
+  - `compiler`: add minsize attribute for -Oz
+  - `compiler`: add "target-cpu" and "target-features" attributes
+  - `compiler`: fix indices into strings and arrays
+  - `compiler`: fix string compare functions
+  - `interp`: simplify some code to avoid some errors
+  - `interp`: support recursive globals (like linked lists) in globals
+  - `interp`: support constant globals
+  - `interp`: fix reverting of extractvalue/insertvalue with multiple indices
+  - `transform`: work around renamed return type after merging LLVM modules
+* **standard library**
+  - `internal/bytealg`: fix indexing error in Compare()
+  - `machine`: support Pin.Get() function when the pin is configured as output
+  - `net`, `syscall`: Reduce code duplication by switching to internal/itoa.
+  - `os`: don't try to read executable path on baremetal
+  - `os`: implement Getwd
+  - `os`: add File.WriteString and File.WriteAt
+  - `reflect`: fix type.Size() to account for struct padding
+  - `reflect`: don't construct an interface-in-interface value
+  - `reflect`: implement Value.Elem() for interface values
+  - `reflect`: fix Value.Index() in a specific case
+  - `reflect`: add support for DeepEqual
+  - `runtime`: add another set of invalid unicode runes to encodeUTF8()
+  - `runtime`: only initialize os.runtime_args when needed
+  - `runtime`: only use CRLF on baremetal systems for println
+  - `runtime/debug`: stub `debug.SetMaxStack`
+  - `runtime/debug`: stub `debug.Stack`
+  - `testing`: add a stub for t.Parallel()
+  - `testing`: add support for -test.short flag
+  - `testing`: stub B.ReportAllocs()
+  - `testing`: add `testing.Verbose`
+  - `testing`: stub `testing.AllocsPerRun`
+* **targets**
+  - fix gen-device-svd to handle 64-bit values
+  - add CPU and Features property to all targets
+  - match LLVM triple to the one Clang uses
+  - `atsam`: simplify definition of SERCOM UART, I2C and SPI peripherals
+  - `atsam`: move I2S0 to machine file
+  - `esp32`: fix SPI configuration
+  - `esp32c3`: add support for GDB debugging
+  - `esp32c3`: add support for CPU interrupts
+  - `esp32c3`: use tasks scheduler by default
+  - `fe310`: increase CPU frequency from 16MHz to 320MHz
+  - `fe310`: add support for bit banging drivers
+  - `linux`: build static binaries using musl
+  - `linux`: reduce binary size by calling `write` instead of `putchar`
+  - `linux`: add support for GOARM
+  - `riscv`: implement 32-bit atomic operations
+  - `riscv`: align the heap to 16 bytes
+  - `riscv`: switch to tasks-based scheduler
+  - `rp2040`: add CPUFrequency()
+  - `rp2040`: improve I2C baud rate configuration
+  - `rp2040`: add pin interrupt API
+  - `rp2040`: refactor PWM code and fix Period calculation
+  - `stm32f103`: fix SPI
+  - `stm32f103`: make SPI frequency selection more flexible
+  - `qemu`: signal correct exit code to QEMU
+  - `wasi`: run C/C++ constructors at startup
+  - `wasm`: ensure heapptr is aligned
+  - `wasm`: update wasi-libc dependency
+  - `wasm`: wasi: use asyncify
+  - `wasm`: support `-scheduler=none`
+  - `windows`: add support for Windows (amd64 only for now)
+* **boards**
+  - `feather-stm32f405`, `feather-rp2040`: add I2C pin names
+  - `m5stack-core2`: add M5Stack Core2
+  - `nano-33-ble`: SoftDevice s140v7 support
+  - `nano-33-ble`: add constants for more on-board pins
+
+
+0.20.0
+---
+
+* **command line**
+  - add support for Go 1.17
+  - improve Go version detection
+  - add support for the Black Magic Probe (BMP)
+  - add a flag for creating cpu profiles
+* **compiler**
+  - `builder:` list libraries at the end of the linker command
+  - `builder:` strip debug information at link time instead of at compile time
+  - `builder:` add missing error check for `ioutil.TempFile()`
+  - `builder:` simplify running of jobs
+  - `compiler:` move LLVM math builtin support into the compiler
+  - `compiler:` move math aliases from the runtime to the compiler
+  - `compiler:` add aliases for many hashing packages
+  - `compiler:` add `*ssa.MakeSlice` bounds tests
+  - `compiler:` fix max possible slice
+  - `compiler:` add support for new language features of Go 1.17
+  - `compiler:` fix equally named structs in different scopes
+  - `compiler:` avoid zero-sized alloca in channel operations
+  - `interp:` don't ignore array indices for untyped objects
+  - `interp:` keep reverted package initializers in order
+  - `interp:` fix bug in compiler-time/run-time package initializers
+  - `loader:` fix panic in CGo files with syntax errors
+  - `transform:` improve GC stack slot pass to work around a bug
+* **standard library**
+  - `crypto/rand`: switch to `arc4random_buf`
+  - `math:` fix `math.Max` and `math.Min`
+  - `math/big`: fix undefined symbols error
+  - `net:` add MAC address implementation
+  - `os:` implement `os.Executable`
+  - `os:` add `SEEK_SET`, `SEEK_CUR`, and `SEEK_END`
+  - `reflect:` add StructField.IsExported method
+  - `runtime:` reset heapptr to heapStart after preinit()
+  - `runtime:` add `subsections_via_symbols` to assembly files on darwin
+  - `testing:` add subset implementation of Benchmark
+  - `testing:` test testing package using `tinygo test`
+  - `testing:` add support for the `-test.v` flag
+* **targets**
+  - `386:` bump minimum requirement to the Pentium 4
+  - `arm:` switch to Thumb instruction set on ARM
+  - `atsamd:` fix copy-paste error for atsamd21/51 calibTrim block
+  - `baremetal`,`wasm`: support command line params and environment variables
+  - `cortexm:` fix stack overflow because of unaligned stacks
+  - `esp32c3:` add support for the ESP32-C3 from Espressif
+  - `nrf52840:` fix ram size
+  - `nxpmk66f18:` fix a suspicious bitwise operation
+  - `rp2040:` add SPI support
+  - `rp2040:` add I2C support
+  - `rp2040:` add PWM implementation
+  - `rp2040:` add openocd configuration
+  - `stm32:` add support for PortMask* functions for WS2812 support
+  - `unix:` fix time base for time.Now()
+  - `unix:` check for mmap error and act accordingly
+  - `wasm:` override dlmalloc heap implementation from wasi-libc
+  - `wasm:` align heap to 16 bytes
+  - `wasm:` add support for the crypto/rand package
+* **boards**
+  - add `DefaultUART` to adafruit boards
+  - `arduino-mkrwifi1010:` add board definition for Arduino MKR WiFi 1010
+  - `arduino-mkrwifi1010:` fix pin definition of `NINA_RESETN`
+  - `feather-nrf52:` fix pin definition of uart
+  - `feather-rp2040:` add pin name definition
+  - `gameboy-advance:` fix ROM header
+  - `mdbt50qrx-uf2:` add Raytac MDBT50Q-RX Dongle with TinyUF2
+  - `nano-rp2040:` define `NINA_SPI` and fix wifinina pins
+  - `teensy40:` enable hardware UART reconfiguration, fix receive watermark interrupt
+
+
+0.19.0
+---
+
+* **command line**
+  - don't consider compile-only tests as failing
+  - add -test flag for `tinygo list`
+  - escape commands while printing them with the -x flag
+  - make flash-command portable and safer to use
+  - use `extended-remote` instead of `remote` in GDB
+  - detect specific serial port IDs based on USB vid/pid
+  - add a flag to the command line to select the serial implementation
+* **compiler**
+  - `cgo`: improve constant parser
+  - `compiler`: support chained interrupt handlers
+  - `compiler`: add support for running a builtin in a goroutine
+  - `compiler`: do not emit nil checks for loading closure variables
+  - `compiler`: skip context parameter when starting regular goroutine
+  - `compiler`: refactor method names
+  - `compiler`: add function and global section pragmas
+  - `compiler`: implement `syscall.rawSyscallNoError` in inline assembly
+  - `interp`: ignore inline assembly in markExternal
+  - `interp`: fix a bug in pointer cast workaround
+  - `loader`: fix testing a main package
+* **standard library**
+  - `crypto/rand`: replace this package with a TinyGo version
+  - `machine`: make USBCDC global a pointer
+  - `machine`: make UART objects pointer receivers
+  - `machine`: define Serial as the default output
+  - `net`: add initial support for net.IP
+  - `net`: add more net compatibility
+  - `os`: add stub for os.ReadDir
+  - `os`: add FileMode constants from Go 1.16
+  - `os`: add stubs required for net/http
+  - `os`: implement process related functions
+  - `reflect`: implement AppendSlice
+  - `reflect`: add stubs required for net/http
+  - `runtime`: make task.Data a 64-bit integer to avoid overflow
+  - `runtime`: expose memory stats
+  - `sync`: implement NewCond
+  - `syscall`: fix int type in libc version
+* **targets**
+  - `cortexm`: do not disable interrupts on abort
+  - `cortexm`: bump default stack size to 2048 bytes
+  - `nrf`: avoid heap allocation in waitForEvent
+  - `nrf`: don't trigger a heap allocation in SPI.Transfer
+  - `nrf52840`: add support for flashing with the BOSSA tool
+  - `rp2040`: add support for GPIO input
+  - `rp2040`: add basic support for ADC
+  - `rp2040`: gpio and adc pin definitions
+  - `rp2040`: implement UART
+  - `rp2040`: patch elf to checksum 2nd stage boot
+  - `stm32`: add PWM for most chips
+  - `stm32`: add support for pin interrupts
+  - `stm32f103`: add support for PinInputPullup / PinInputPulldown
+  - `wasi`: remove wasm build tag
+* **boards**
+  - `feather-rp2040`: add support for this board
+  - `feather-nrf52840-sense`: add board definition for this board
+  - `pca10059`: support flashing from Windows
+  - `nano-rp2040`: add this board
+  - `nano-33-ble`: add support for this board
+  - `pico`: add the Raspberry Pi Pico board with the new RP2040 chip
+  - `qtpy`: add pin for neopixels
+  - all: add definition for ws2812 for supported boards
+
+
+0.18.0
+---
+
+* **command line**
+  - drop support for Go 1.11 and 1.12
+  - throw an error when no target is specified on Windows
+  - improve error messages in `getDefaultPort()`, support for multiple ports
+  - remove `-cflags` and `-ldflags` flags
+  - implement `-ldflags="-X ..."`
+  - add `-print-allocs` flag that lets you print all heap allocations
+  - openocd commands in tinygo command line
+  - add `-llvm-features` parameter
+  - match `go test` output
+  - discover USB ports only, this will ignore f.ex. bluetooth
+  - use physicmal path instead of cached GOROOT in function getGoroot
+  - add goroot for snap installs
+* **compiler**
+  - `builder`: add support for `-opt=0`
+  - `builder`, `compiler`: compile and cache packages in parallel
+  - `builder`: run interp per package
+  - `builder`: cache C and assembly file outputs
+  - `builder`: add support for `-x` flag to print commands
+  - `builder`: add optsize attribute while building the package
+  - `builder`: run function passes per package
+  - `builder`: hard code Clang compiler
+  - `compiler`: do not use `llvm.GlobalContext()`
+  - `compiler`: remove SimpleDCE pass
+  - `compiler`: do not emit nil checks for `*ssa.Alloc` instructions
+  - `compiler`: merge `runtime.typecodeID` and runtime.typeInInterface
+  - `compiler`: do not check for impossible type asserts
+  - `compiler`: fix use of global context: `llvm.Int32Type()`
+  - `compiler`: add interface IR test
+  - `compiler`: fix lack of method name in interface matching
+  - `compiler`: fix "fragment covers entire variable" bug
+  - `compiler`: optimize string literals and globals
+  - `compiler`: decouple func lowering from interface type codes
+  - `compiler`: add function attributes to some runtime calls
+  - `compiler`: improve position information in error messages
+  - `cgo`: add support for CFLAGS in .c files
+  - `interp`: support GEP on fixed (MMIO) addresses
+  - `interp`: handle `(reflect.Type).Elem()`
+  - `interp`: add support for runtime.interfaceMethod
+  - `interp`: make toLLVMValue return an error instead of panicking
+  - `interp`: add support for switch statement
+  - `interp`: fix phi instruction
+  - `interp`: remove map support
+  - `interp`: support extractvalue/insertvalue with multiple operands
+  - `transform`: optimize string comparisons against ""
+  - `transform`: optimize `reflect.Type` `Implements()` method
+  - `transform`: fix bug in interface lowering when signatures are renamed
+  - `transform`: don't rely on struct name of `runtime.typecodeID`
+  - `transform`: use IPSCCP pass instead of the constant propagation pass
+  - `transform`: fix func lowering assertion failure
+  - `transform`: do not lower zero-sized alloc to alloca
+  - `transform`: split interface and reflect lowering
+* **standard library**
+  - `runtime`: add dummy debug package
+  - `machine`: fix data shift/mask in newUSBSetup
+  - `machine`: make `machine.I2C0` and similar objects pointers
+  - `machine`: unify usbcdc code
+  - `machine`: refactor PWM support
+  - `machine`: avoid heap allocations in USB code
+  - `reflect`: let `reflect.Type` be of interface type
+  - `reflect`: implement a number of stub functions
+  - `reflect`: check for access in the `Interface` method call
+  - `reflect`: fix `AssignableTo` and `Implements` methods
+  - `reflect`: implement `Value.CanAddr`
+  - `reflect`: implement `Sizeof` and `Alignof` for func values
+  - `reflect`: implement `New` function
+  - `runtime`: implement command line arguments in hosted environments
+  - `runtime`: implement environment variables for Linux
+  - `runtime`: improve timers on nrf, and samd chips
+* **targets**
+  - all: use -Qunused-arguments only for assembly files
+  - `atmega1280`: add PWM support
+  - `attiny`: remove dummy UART
+  - `atsamd21`: improve SPI
+  - `atsamd51`: fix PWM support in atsamd51p20
+  - `atsamd5x`: improve SPI
+  - `atsamd51`, `atsame5x`: unify samd51 and same5x
+  - `atsamd51`, `atsamd21`: fix `ADC.Get()` value at 8bit and 10bit
+  - `atsame5x`: add support for CAN
+  - `avr`: remove I2C stubs from attiny support
+  - `cortexm`: check for `arm-none-eabi-gdb` and `gdb-multiarch` commands
+  - `cortexm`: add `__isr_vector` symbol
+  - `cortexm`: disable FPU on Cortex-M4
+  - `cortexm`: clean up Cortex-M target files
+  - `fe310`: fix SPI read
+  - `gameboy-advance`: Fix RGBA color interpretation
+  - `nrf52833`: add PWM support
+  - `stm32l0`: use unified UART logic
+  - `stm32`: move f103 (bluepill) to common i2c code
+  - `stm32`: separate altfunc selection for UART Tx/Rx
+  - `stm32`: i2c implementation for F7, L5 and L4 MCUs
+  - `stm32`: make SPI CLK fast to fix data issue
+  - `stm32`: support SPI on L4 series
+  - `unix`: avoid possible heap allocation with `-opt=0`
+  - `unix`: use conservative GC by default
+  - `unix`: use the tasks scheduler instead of coroutines
+  - `wasi`: upgrade WASI version to wasi_snapshot_preview1
+  - `wasi`: darwin: support basic file io based on libc
+  - `wasm`: only export explicitly exported functions
+  - `wasm`: use WASI ABI for exit function
+  - `wasm`: scan globals conservatively
+* **boards**
+  - `arduino-mega1280`: add support for the Arduino Mega 1280
+  - `arduino-nano-new`: Add Arduino Nano w/ New Bootloader target
+  - `atsame54-xpro`: add initial support this board
+  - `feather-m4-can`: add initial support for this board
+  - `grandcentral-m4`: add board support for Adafruit Grand Central M4 (SAMD51)
+  - `lgt92`: update to new UART structure
+  - `microbit`: remove LED constant
+  - `microbit-v2`: add support for S113 SoftDevice
+  - `nucleol432`: add support for this board
+  - `nucleo-l031k6`: add this board
+  - `pca10059`: initial support for this board
+  - `qtpy`: fix msd-volume-name
+  - `qtpy`: fix i2c setting
+  - `teensy40`: move txBuffer allocation to UART declaration
+  - `teensy40`: add UART0 as alias for UART1
+
+
 0.17.0
 
 ---

CONTRIBUTING.md

@@ -1,52 +1 @@
-# How to contribute
-
-Thank you for your interest in improving TinyGo.
-
-We would like your help to make this project better, so we appreciate any contributions. See if one of the following descriptions matches your situation:
-
-### New to TinyGo
-
-We'd love to get your feedback on getting started with TinyGo. Run into any difficulty, confusion, or anything else? You are not alone. We want to know about your experience, so we can help the next people. Please open a Github issue with your questions, or you can also get in touch directly with us on our Slack channel at [https://gophers.slack.com/messages/CDJD3SUP6](https://gophers.slack.com/messages/CDJD3SUP6).
-
-### Something in TinyGo is not working as you expect
-
-Please open a Github issue with your problem, and we will be happy to assist.
-
-### Something in Go that you want/need does not appear to be in TinyGo
-
-We probably have not implemented it yet. Please take a look at our [Roadmap](https://github.com/tinygo-org/tinygo/wiki/Roadmap). Your pull request adding the functionality to TinyGo would be greatly appreciated.
-
-Please open a Github issue. We want to help, and also make sure that there is no duplications of efforts. Sometimes what you need is already being worked on by someone else.
-
-A long tail of small (and large) language features haven't been implemented yet. In almost all cases, the compiler will show a `todo:` error from `compiler/compiler.go` when you try to use it. You can try implementing it, or open a bug report with a small code sample that fails to compile.
-
-### Some specific hardware you want to use does not appear to be in TinyGo
-
-As above, we probably have not implemented it yet. Your contribution adding the hardware support to TinyGo would be greatly appreciated.
-
-Please start by opening a Github issue. We want to help you to help us to help you.
-
-Lots of targets/boards are still unsupported. Adding an architecture often requires a few compiler changes, but if the architecture is supported you can try implementing support for a new chip or board in `src/runtime`. For details, see [this wiki entry on adding archs/chips/boards](https://github.com/tinygo-org/tinygo/wiki/Adding-a-new-board).
-
-Microcontrollers have lots of peripherals (I2C, SPI, ADC, etc.) and many don't have an implementation yet in the `machine` package. Adding support for new peripherals is very useful.
-
-## How to use our Github repository
-
-The `release` branch of this repo will always have the latest released version of TinyGo. All of the active development work for the next release will take place in the `dev` branch. TinyGo will use semantic versioning and will create a tag/release for each release.
-
-Here is how to contribute back some code or documentation:
-
-- Fork repo
-- Create a feature branch off of the `dev` branch
-- Make some useful change
-- Make sure the tests still pass
-- Submit a pull request against the `dev` branch.
-- Be kind
-
-## How to run tests
-
-To run the tests:
-
-```
-make test
-```
+Please take a look at our [Contributing](https://tinygo.org/docs/guides/contributing/) page on our web site for details. Thank you.

Dockerfile

@@ -1,79 +1,50 @@
-# TinyGo base stage installs the most recent Go 1.15.x, LLVM 11 and the TinyGo compiler itself.
-FROM golang:1.15 AS tinygo-base
+# tinygo-llvm stage obtains the llvm source for TinyGo
+FROM golang:1.18 AS tinygo-llvm
 
-RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
-    echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster-11 main" >> /etc/apt/sources.list && \
-    apt-get update && \
-    apt-get install -y llvm-11-dev libclang-11-dev lld-11 git
+RUN apt-get update && \
+    apt-get install -y apt-utils make cmake clang-11 binutils-avr gcc-avr avr-libc ninja-build
+
+COPY ./Makefile /tinygo/Makefile
+
+RUN cd /tinygo/ && \
+    make llvm-source
+
+# tinygo-llvm-build stage build the custom llvm with xtensa support
+FROM tinygo-llvm AS tinygo-llvm-build
+
+RUN cd /tinygo/ && \
+    make llvm-build
+
+# tinygo-xtensa stage installs tools needed for ESP32
+FROM tinygo-llvm-build AS tinygo-xtensa
+
+ARG xtensa_version="1.22.0-80-g6c4433a-5.2.0"
+RUN cd /tmp/ && \
+    wget -q https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-${xtensa_version}.tar.gz && \
+    tar xzf xtensa-esp32-elf-linux64-${xtensa_version}.tar.gz && \
+    cp ./xtensa-esp32-elf/bin/xtensa-esp32-elf-ld /usr/local/bin/ && \
+    rm -rf /tmp/xtensa*
+
+# tinygo-compiler stage builds the compiler itself
+FROM tinygo-xtensa AS tinygo-compiler
 
 COPY . /tinygo
 
-# remove submodules directories and re-init them to fix any hard-coded paths
-# after copying the tinygo directory in the previous step.
+# update submodules
 RUN cd /tinygo/ && \
-    rm -rf ./lib/* && \
+    rm -rf ./lib/*/ && \
     git submodule sync && \
     git submodule update --init --recursive --force
 
-COPY ./lib/picolibc-include/* /tinygo/lib/picolibc-include/
+RUN cd /tinygo/ && \
+    make
+
+# tinygo-tools stage installs the needed dependencies to compile TinyGo programs for all platforms.
+FROM tinygo-compiler AS tinygo-tools
 
 RUN cd /tinygo/ && \
-    go install /tinygo/
-
-# tinygo-wasm stage installs the needed dependencies to compile TinyGo programs for WASM.
-FROM tinygo-base AS tinygo-wasm
-
-COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /tinygo/src /tinygo/src
-COPY --from=tinygo-base /tinygo/targets /tinygo/targets
-
-RUN cd /tinygo/ && \
-    apt-get update && \
-    apt-get install -y make clang-11 libllvm11 lld-11 && \
-    make wasi-libc
-
-# tinygo-avr stage installs the needed dependencies to compile TinyGo programs for AVR microcontrollers.
-FROM tinygo-base AS tinygo-avr
-
-COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /tinygo/src /tinygo/src
-COPY --from=tinygo-base /tinygo/targets /tinygo/targets
-COPY --from=tinygo-base /tinygo/Makefile /tinygo/
-COPY --from=tinygo-base /tinygo/tools /tinygo/tools
-COPY --from=tinygo-base /tinygo/lib /tinygo/lib
-
-RUN cd /tinygo/ && \
-    apt-get update && \
-    apt-get install -y apt-utils make binutils-avr gcc-avr avr-libc && \
-    make gen-device-avr && \
-    apt-get autoremove -y && \
-    apt-get clean
-
-# tinygo-arm stage installs the needed dependencies to compile TinyGo programs for ARM microcontrollers.
-FROM tinygo-base AS tinygo-arm
-
-COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /tinygo/src /tinygo/src
-COPY --from=tinygo-base /tinygo/targets /tinygo/targets
-COPY --from=tinygo-base /tinygo/Makefile /tinygo/
-COPY --from=tinygo-base /tinygo/tools /tinygo/tools
-COPY --from=tinygo-base /tinygo/lib /tinygo/lib
-
-RUN cd /tinygo/ && \
-    apt-get update && \
-    apt-get install -y apt-utils make clang-11 && \
-    make gen-device-nrf && make gen-device-stm32
-
-# tinygo-all stage installs the needed dependencies to compile TinyGo programs for all platforms.
-FROM tinygo-wasm AS tinygo-all
-
-COPY --from=tinygo-base /tinygo/Makefile /tinygo/
-COPY --from=tinygo-base /tinygo/tools /tinygo/tools
-COPY --from=tinygo-base /tinygo/lib /tinygo/lib
-
-RUN cd /tinygo/ && \
-    apt-get update && \
-    apt-get install -y apt-utils make clang-11 binutils-avr gcc-avr avr-libc && \
-    make gen-device
+    make wasi-libc binaryen && \
+    make gen-device -j4 && \
+    cp build/* $GOPATH/bin/
 
 CMD ["tinygo"]

LICENSE

@@ -1,7 +1,7 @@
-Copyright (c) 2018-2021 TinyGo Authors. All rights reserved.
+Copyright (c) 2018-2022 The TinyGo Authors. All rights reserved.
 
 TinyGo includes portions of the Go standard library.
-Copyright (c) 2009-2021 The Go Authors. All rights reserved.
+Copyright (c) 2009-2022 The Go Authors. All rights reserved.
 
 TinyGo includes portions of LLVM, which is under the Apache License v2.0 with
 LLVM Exceptions. See https://llvm.org/LICENSE.txt for license information.

Makefile

@@ -9,20 +9,34 @@ CLANG_SRC ?= $(LLVM_PROJECTDIR)/clang
 LLD_SRC ?= $(LLVM_PROJECTDIR)/lld
 
 # Try to autodetect LLVM build tools.
-detect = $(shell command -v $(1) 2> /dev/null && echo $(1))
-CLANG ?= $(word 1,$(abspath $(call detect,llvm-build/bin/clang))$(call detect,clang-11)$(call detect,clang-10)$(call detect,clang))
-LLVM_AR ?= $(word 1,$(abspath $(call detect,llvm-build/bin/llvm-ar))$(call detect,llvm-ar-11)$(call detect,llvm-ar-10)$(call detect,llvm-ar))
-LLVM_NM ?= $(word 1,$(abspath $(call detect,llvm-build/bin/llvm-nm))$(call detect,llvm-nm-11)$(call detect,llvm-nm-10)$(call detect,llvm-nm))
+# Versions are listed here in descending priority order.
+LLVM_VERSIONS = 14 13 12 11
+errifempty = $(if $(1),$(1),$(error $(2)))
+detect = $(shell which $(call errifempty,$(firstword $(foreach p,$(2),$(shell command -v $(p) 2> /dev/null && echo $(p)))),failed to locate $(1) at any of: $(2)))
+toolSearchPathsVersion = $(1)-$(2)
+ifeq ($(shell uname -s),Darwin)
+	# Also explicitly search Brew's copy, which is not in PATH by default.
+	BREW_PREFIX := $(shell brew --prefix)
+	toolSearchPathsVersion += $(BREW_PREFIX)/opt/llvm@$(2)/bin/$(1)-$(2) $(BREW_PREFIX)/opt/llvm@$(2)/bin/$(1)
+endif
+# First search for a custom built copy, then move on to explicitly version-tagged binaries, then just see if the tool is in path with its normal name.
+findLLVMTool = $(call detect,$(1),$(abspath llvm-build/bin/$(1)) $(foreach ver,$(LLVM_VERSIONS),$(call toolSearchPathsVersion,$(1),$(ver))) $(1))
+CLANG ?= $(call findLLVMTool,clang)
+LLVM_AR ?= $(call findLLVMTool,llvm-ar)
+LLVM_NM ?= $(call findLLVMTool,llvm-nm)
 
 # Go binary and GOROOT to select
 GO ?= go
 export GOROOT = $(shell $(GO) env GOROOT)
 
+# Flags to pass to go test.
+GOTESTFLAGS ?= -v
+
 # md5sum binary
 MD5SUM = md5sum
 
 # tinygo binary for tests
-TINYGO ?= $(word 1,$(call detect,tinygo)$(call detect,build/tinygo))
+TINYGO ?= $(call detect,tinygo,tinygo $(CURDIR)/build/tinygo)
 
 # Use CCACHE for LLVM if possible
 ifneq (, $(shell command -v ccache 2> /dev/null))
@@ -36,9 +50,41 @@ else
     LLVM_OPTION += '-DLLVM_ENABLE_ASSERTIONS=OFF'
 endif
 
-.PHONY: all tinygo test $(LLVM_BUILDDIR) llvm-source clean fmt gen-device gen-device-nrf gen-device-nxp gen-device-avr
+# Cross compiling support.
+ifneq ($(CROSS),)
+    CC = $(CROSS)-gcc
+    CXX = $(CROSS)-g++
+    LLVM_OPTION += \
+        -DCMAKE_C_COMPILER=$(CC) \
+        -DCMAKE_CXX_COMPILER=$(CXX) \
+        -DLLVM_DEFAULT_TARGET_TRIPLE=$(CROSS) \
+        -DCROSS_TOOLCHAIN_FLAGS_NATIVE="-UCMAKE_C_COMPILER;-UCMAKE_CXX_COMPILER"
+    ifeq ($(CROSS), arm-linux-gnueabihf)
+        # Assume we're building on a Debian-like distro, with QEMU installed.
+        LLVM_CONFIG_PREFIX = qemu-arm -L /usr/arm-linux-gnueabihf/
+        # The CMAKE_SYSTEM_NAME flag triggers cross compilation mode.
+        LLVM_OPTION += \
+            -DCMAKE_SYSTEM_NAME=Linux \
+            -DLLVM_TARGET_ARCH=ARM
+        GOENVFLAGS = GOARCH=arm CC=$(CC) CXX=$(CXX) CGO_ENABLED=1
+        BINARYEN_OPTION += -DCMAKE_C_COMPILER=$(CC) -DCMAKE_CXX_COMPILER=$(CXX)
+    else ifeq ($(CROSS), aarch64-linux-gnu)
+        # Assume we're building on a Debian-like distro, with QEMU installed.
+        LLVM_CONFIG_PREFIX = qemu-aarch64 -L /usr/aarch64-linux-gnu/
+        # The CMAKE_SYSTEM_NAME flag triggers cross compilation mode.
+        LLVM_OPTION += \
+            -DCMAKE_SYSTEM_NAME=Linux \
+            -DLLVM_TARGET_ARCH=AArch64
+        GOENVFLAGS = GOARCH=arm64 CC=$(CC) CXX=$(CXX) CGO_ENABLED=1
+        BINARYEN_OPTION += -DCMAKE_C_COMPILER=$(CC) -DCMAKE_CXX_COMPILER=$(CXX)
+    else
+        $(error Unknown cross compilation target: $(CROSS))
+    endif
+endif
 
-LLVM_COMPONENTS = all-targets analysis asmparser asmprinter bitreader bitwriter codegen core coroutines coverage debuginfodwarf executionengine frontendopenmp instrumentation interpreter ipo irreader linker lto mc mcjit objcarcopts option profiledata scalaropts support target
+.PHONY: all tinygo test $(LLVM_BUILDDIR) llvm-source clean fmt gen-device gen-device-nrf gen-device-nxp gen-device-avr gen-device-rp
+
+LLVM_COMPONENTS = all-targets analysis asmparser asmprinter bitreader bitwriter codegen core coroutines coverage debuginfodwarf debuginfopdb executionengine frontendopenmp instrumentation interpreter ipo irreader libdriver linker lto mc mcjit objcarcopts option profiledata scalaropts support target windowsmanifest
 
 ifeq ($(OS),Windows_NT)
     EXE = .exe
@@ -54,32 +100,37 @@ ifeq ($(OS),Windows_NT)
     CGO_LDFLAGS += -static -static-libgcc -static-libstdc++
     CGO_LDFLAGS_EXTRA += -lversion
 
-    LIBCLANG_NAME = libclang
+    USE_SYSTEM_BINARYEN ?= 1
 
 else ifeq ($(shell uname -s),Darwin)
     MD5SUM = md5
-    LIBCLANG_NAME = clang
+
+    CGO_LDFLAGS += -lxar
+
+    USE_SYSTEM_BINARYEN ?= 1
+
 else ifeq ($(shell uname -s),FreeBSD)
     MD5SUM = md5
-    LIBCLANG_NAME = clang
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 else
-    LIBCLANG_NAME = clang
     START_GROUP = -Wl,--start-group
     END_GROUP = -Wl,--end-group
 endif
 
 # Libraries that should be linked in for the statically linked Clang.
-CLANG_LIB_NAMES = clangAnalysis clangARCMigrate clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangStaticAnalyzerCheckers clangStaticAnalyzerCore clangStaticAnalyzerFrontend clangTooling clangToolingASTDiff clangToolingCore clangToolingInclusions
+CLANG_LIB_NAMES = clangAnalysis clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangTooling clangToolingASTDiff clangToolingCore clangToolingInclusions
 CLANG_LIBS = $(START_GROUP) $(addprefix -l,$(CLANG_LIB_NAMES)) $(END_GROUP) -lstdc++
 
 # Libraries that should be linked in for the statically linked LLD.
-LLD_LIB_NAMES = lldCOFF lldCommon lldCore lldDriver lldELF lldMachO lldMinGW lldReaderWriter lldWasm lldYAML
+LLD_LIB_NAMES = lldCOFF lldCommon lldELF lldMachO lldMinGW lldWasm
 LLD_LIBS = $(START_GROUP) $(addprefix -l,$(LLD_LIB_NAMES)) $(END_GROUP)
 
 # Other libraries that are needed to link TinyGo.
-EXTRA_LIB_NAMES = LLVMInterpreter
+EXTRA_LIB_NAMES = LLVMInterpreter LLVMMCA LLVMX86TargetMCA
+
+# All libraries to be built and linked with the tinygo binary (lib/lib*.a).
+LIB_NAMES = clang $(CLANG_LIB_NAMES) $(LLD_LIB_NAMES) $(EXTRA_LIB_NAMES)
 
 # These build targets appear to be the only ones necessary to build all TinyGo
 # dependencies. Only building a subset significantly speeds up rebuilding LLVM.
@@ -87,27 +138,26 @@ EXTRA_LIB_NAMES = LLVMInterpreter
 # library path (for ninja).
 # This list also includes a few tools that are necessary as part of the full
 # TinyGo build.
-NINJA_BUILD_TARGETS = clang llvm-config llvm-ar llvm-nm $(addprefix lib/lib,$(addsuffix .a,$(LIBCLANG_NAME) $(CLANG_LIB_NAMES) $(LLD_LIB_NAMES) $(EXTRA_LIB_NAMES)))
+NINJA_BUILD_TARGETS = clang llvm-config llvm-ar llvm-nm $(addprefix lib/lib,$(addsuffix .a,$(LIB_NAMES)))
 
 # For static linking.
 ifneq ("$(wildcard $(LLVM_BUILDDIR)/bin/llvm-config*)","")
-    CGO_CPPFLAGS+=$(shell $(LLVM_BUILDDIR)/bin/llvm-config --cppflags) -I$(abspath $(LLVM_BUILDDIR))/tools/clang/include -I$(abspath $(CLANG_SRC))/include -I$(abspath $(LLD_SRC))/include
+    CGO_CPPFLAGS+=$(shell $(LLVM_CONFIG_PREFIX) $(LLVM_BUILDDIR)/bin/llvm-config --cppflags) -I$(abspath $(LLVM_BUILDDIR))/tools/clang/include -I$(abspath $(CLANG_SRC))/include -I$(abspath $(LLD_SRC))/include
     CGO_CXXFLAGS=-std=c++14
-    CGO_LDFLAGS+=$(abspath $(LLVM_BUILDDIR))/lib/lib$(LIBCLANG_NAME).a -L$(abspath $(LLVM_BUILDDIR)/lib) $(CLANG_LIBS) $(LLD_LIBS) $(shell $(LLVM_BUILDDIR)/bin/llvm-config --ldflags --libs --system-libs $(LLVM_COMPONENTS)) -lstdc++ $(CGO_LDFLAGS_EXTRA)
+    CGO_LDFLAGS+=-L$(abspath $(LLVM_BUILDDIR)/lib) -lclang $(CLANG_LIBS) $(LLD_LIBS) $(shell $(LLVM_CONFIG_PREFIX) $(LLVM_BUILDDIR)/bin/llvm-config --ldflags --libs --system-libs $(LLVM_COMPONENTS)) -lstdc++ $(CGO_LDFLAGS_EXTRA)
 endif
 
-
 clean:
 	@rm -rf build
 
-FMT_PATHS = ./*.go builder cgo compiler interp loader src/device/arm src/examples src/machine src/os src/reflect src/runtime src/sync src/syscall src/internal/reflectlite transform
+FMT_PATHS = ./*.go builder cgo compiler interp loader src/device/arm src/examples src/machine src/os src/reflect src/runtime src/sync src/syscall src/testing src/internal/reflectlite transform
 fmt:
 	@gofmt -l -w $(FMT_PATHS)
 fmt-check:
 	@unformatted=$$(gofmt -l $(FMT_PATHS)); [ -z "$$unformatted" ] && exit 0; echo "Unformatted:"; for fn in $$unformatted; do echo "  $$fn"; done; exit 1
 
 
-gen-device: gen-device-avr gen-device-esp gen-device-nrf gen-device-sam gen-device-sifive gen-device-kendryte gen-device-nxp
+gen-device: gen-device-avr gen-device-esp gen-device-nrf gen-device-sam gen-device-sifive gen-device-kendryte gen-device-nxp gen-device-rp
 ifneq ($(STM32), 0)
 gen-device: gen-device-stm32
 endif
@@ -124,6 +174,7 @@ build/gen-device-svd: ./tools/gen-device-svd/*.go
 
 gen-device-esp: build/gen-device-svd
 	./build/gen-device-svd -source=https://github.com/posborne/cmsis-svd/tree/master/data/Espressif-Community -interrupts=software lib/cmsis-svd/data/Espressif-Community/ src/device/esp/
+	./build/gen-device-svd -source=https://github.com/posborne/cmsis-svd/tree/master/data/Espressif -interrupts=software lib/cmsis-svd/data/Espressif/ src/device/esp/
 	GO111MODULE=off $(GO) fmt ./src/device/esp
 
 gen-device-nrf: build/gen-device-svd
@@ -150,61 +201,188 @@ gen-device-stm32: build/gen-device-svd
 	./build/gen-device-svd -source=https://github.com/tinygo-org/stm32-svd lib/stm32-svd/svd src/device/stm32/
 	GO111MODULE=off $(GO) fmt ./src/device/stm32
 
+gen-device-rp: build/gen-device-svd
+	./build/gen-device-svd -source=https://github.com/posborne/cmsis-svd/tree/master/data/RaspberryPi lib/cmsis-svd/data/RaspberryPi/ src/device/rp/
+	GO111MODULE=off $(GO) fmt ./src/device/rp
 
 # Get LLVM sources.
-$(LLVM_PROJECTDIR)/README.md:
-	git clone -b xtensa_release_11.0.0 --depth=1 https://github.com/tinygo-org/llvm-project $(LLVM_PROJECTDIR)
-llvm-source: $(LLVM_PROJECTDIR)/README.md
+$(LLVM_PROJECTDIR)/llvm:
+	git clone -b xtensa_release_14.0.0-patched --depth=1 https://github.com/tinygo-org/llvm-project $(LLVM_PROJECTDIR)
+llvm-source: $(LLVM_PROJECTDIR)/llvm
 
 # Configure LLVM.
 TINYGO_SOURCE_DIR=$(shell pwd)
-$(LLVM_BUILDDIR)/build.ninja: llvm-source
-	mkdir -p $(LLVM_BUILDDIR); cd $(LLVM_BUILDDIR); cmake -G Ninja $(TINYGO_SOURCE_DIR)/$(LLVM_PROJECTDIR)/llvm "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64;RISCV;WebAssembly" "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=AVR;Xtensa" -DCMAKE_BUILD_TYPE=Release -DLIBCLANG_BUILD_STATIC=ON -DLLVM_ENABLE_TERMINFO=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_ENABLE_LIBEDIT=OFF -DLLVM_ENABLE_Z3_SOLVER=OFF -DLLVM_ENABLE_OCAMLDOC=OFF -DLLVM_ENABLE_LIBXML2=OFF -DLLVM_ENABLE_PROJECTS="clang;lld" -DLLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD=OFF $(LLVM_OPTION)
+$(LLVM_BUILDDIR)/build.ninja:
+	mkdir -p $(LLVM_BUILDDIR) && cd $(LLVM_BUILDDIR) && cmake -G Ninja $(TINYGO_SOURCE_DIR)/$(LLVM_PROJECTDIR)/llvm "-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64;RISCV;WebAssembly" "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=AVR;Xtensa" -DCMAKE_BUILD_TYPE=Release -DLIBCLANG_BUILD_STATIC=ON -DLLVM_ENABLE_TERMINFO=OFF -DLLVM_ENABLE_ZLIB=OFF -DLLVM_ENABLE_LIBEDIT=OFF -DLLVM_ENABLE_Z3_SOLVER=OFF -DLLVM_ENABLE_OCAMLDOC=OFF -DLLVM_ENABLE_LIBXML2=OFF -DLLVM_ENABLE_PROJECTS="clang;lld" -DLLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD=OFF -DCLANG_ENABLE_STATIC_ANALYZER=OFF -DCLANG_ENABLE_ARCMT=OFF $(LLVM_OPTION)
 
 # Build LLVM.
 $(LLVM_BUILDDIR): $(LLVM_BUILDDIR)/build.ninja
-	cd $(LLVM_BUILDDIR); ninja $(NINJA_BUILD_TARGETS)
+	cd $(LLVM_BUILDDIR) && ninja $(NINJA_BUILD_TARGETS)
 
+ifneq ($(USE_SYSTEM_BINARYEN),1)
+# Build Binaryen
+.PHONY: binaryen
+binaryen: build/wasm-opt$(EXE)
+build/wasm-opt$(EXE):
+	mkdir -p build
+	cd lib/binaryen && cmake -G Ninja . -DBUILD_STATIC_LIB=ON $(BINARYEN_OPTION) && ninja bin/wasm-opt$(EXE)
+	cp lib/binaryen/bin/wasm-opt$(EXE) build/wasm-opt$(EXE)
+endif
 
 # Build wasi-libc sysroot
 .PHONY: wasi-libc
 wasi-libc: lib/wasi-libc/sysroot/lib/wasm32-wasi/libc.a
 lib/wasi-libc/sysroot/lib/wasm32-wasi/libc.a:
 	@if [ ! -e lib/wasi-libc/Makefile ]; then echo "Submodules have not been downloaded. Please download them using:\n  git submodule update --init"; exit 1; fi
-	cd lib/wasi-libc && make -j4 WASM_CC=$(CLANG) WASM_AR=$(LLVM_AR) WASM_NM=$(LLVM_NM)
+	cd lib/wasi-libc && make -j4 WASM_CFLAGS="-O2 -g -DNDEBUG" MALLOC_IMPL=none WASM_CC=$(CLANG) WASM_AR=$(LLVM_AR) WASM_NM=$(LLVM_NM)
 
 
 # Build the Go compiler.
 tinygo:
 	@if [ ! -f "$(LLVM_BUILDDIR)/bin/llvm-config" ]; then echo "Fetch and build LLVM first by running:"; echo "  make llvm-source"; echo "  make $(LLVM_BUILDDIR)"; exit 1; fi
-	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) build -buildmode exe -o build/tinygo$(EXE) -tags byollvm -ldflags="-X main.gitSha1=`git rev-parse --short HEAD`" .
-
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GOENVFLAGS) $(GO) build -buildmode exe -o build/tinygo$(EXE) -tags byollvm -ldflags="-X github.com/tinygo-org/tinygo/goenv.GitSha1=`git rev-parse --short HEAD`" .
 test: wasi-libc
-	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test -v -buildmode exe -tags byollvm ./builder ./cgo ./compileopts ./compiler ./interp ./transform .
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=20m -buildmode exe -tags byollvm ./builder ./cgo ./compileopts ./compiler ./interp ./transform .
+
+# Standard library packages that pass tests on darwin, linux, wasi, and windows, but take over a minute in wasi
+TEST_PACKAGES_SLOW = \
+	compress/bzip2 \
+	crypto/dsa \
+	index/suffixarray \
+
+# Standard library packages that pass tests quickly on darwin, linux, wasi, and windows
+TEST_PACKAGES_FAST = \
+	compress/zlib \
+	container/heap \
+	container/list \
+	container/ring \
+	crypto/des \
+	crypto/elliptic/internal/fiat \
+	crypto/internal/subtle \
+	crypto/md5 \
+	crypto/rc4 \
+	crypto/sha1 \
+	crypto/sha256 \
+	crypto/sha512 \
+	debug/macho \
+	embed/internal/embedtest \
+	encoding \
+	encoding/ascii85 \
+	encoding/base32 \
+	encoding/csv \
+	encoding/hex \
+	go/scanner \
+	hash \
+	hash/adler32 \
+	hash/crc64 \
+	hash/fnv \
+	html \
+	internal/itoa \
+	internal/profile \
+	math \
+	math/cmplx \
+	net \
+	net/http/internal/ascii \
+	net/mail \
+	os \
+	path \
+	reflect \
+	sync \
+	testing \
+	testing/iotest \
+	text/scanner \
+	unicode \
+	unicode/utf16 \
+	unicode/utf8 \
+
+# archive/zip requires os.ReadAt, which is not yet supported on windows
+# debug/plan9obj requires os.ReadAt, which is not yet supported on windows
+# io/fs requires os.ReadDir, which is not yet supported on windows or wasi
+# testing/fstest requires os.ReadDir, which is not yet supported on windows or wasi
+# compress/flate fails windows go 1.18, https://github.com/tinygo-org/tinygo/issues/2762
+# compress/lzw fails windows go 1.18 wasi, https://github.com/tinygo-org/tinygo/issues/2762
+
+# Additional standard library packages that pass tests on individual platforms
+TEST_PACKAGES_LINUX := \
+	archive/zip \
+	compress/flate \
+	compress/lzw \
+	debug/dwarf \
+	debug/plan9obj \
+	io/fs \
+	io/ioutil \
+	testing/fstest
+
+TEST_PACKAGES_DARWIN := $(TEST_PACKAGES_LINUX)
+
+TEST_PACKAGES_WINDOWS := \
+	compress/lzw
+
+# Report platforms on which each standard library package is known to pass tests
+jointmp := $(shell echo /tmp/join.$$$$)
+report-stdlib-tests-pass:
+	@for t in $(TEST_PACKAGES_DARWIN); do echo "$$t darwin"; done | sort > $(jointmp).darwin
+	@for t in $(TEST_PACKAGES_LINUX); do echo "$$t linux"; done | sort > $(jointmp).linux
+	@for t in $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_SLOW); do echo "$$t darwin linux wasi windows"; done | sort > $(jointmp).portable
+	@join -a1 -a2 $(jointmp).darwin $(jointmp).linux | \
+	join -a1 -a2 - $(jointmp).portable
+	@rm $(jointmp).*
+
+# Standard library packages that pass tests quickly on the current platform
+ifeq ($(shell uname),Darwin)
+TEST_PACKAGES_HOST := $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_DARWIN)
+endif
+ifeq ($(shell uname),Linux)
+TEST_PACKAGES_HOST := $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_LINUX)
+endif
+ifeq ($(OS),Windows_NT)
+TEST_PACKAGES_HOST := $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_WINDOWS)
+endif
 
 # Test known-working standard library packages.
-# TODO: do this in one command, parallelize, and only show failing tests (no
-# implied -v flag).
+# TODO: parallelize, and only show failing tests (no implied -v flag).
 .PHONY: tinygo-test
 tinygo-test:
-	$(TINYGO) test container/heap
-	$(TINYGO) test container/list
-	$(TINYGO) test container/ring
-	$(TINYGO) test crypto/des
-	$(TINYGO) test encoding/ascii85
-	$(TINYGO) test encoding/base32
-	$(TINYGO) test encoding/hex
-	$(TINYGO) test hash/adler32
-	$(TINYGO) test hash/fnv
-	$(TINYGO) test hash/crc64
-	$(TINYGO) test math
-	$(TINYGO) test math/cmplx
-	$(TINYGO) test text/scanner
-	$(TINYGO) test unicode/utf8
+	$(TINYGO) test $(TEST_PACKAGES_HOST) $(TEST_PACKAGES_SLOW)
+tinygo-test-fast:
+	$(TINYGO) test $(TEST_PACKAGES_HOST)
+tinygo-bench:
+	$(TINYGO) test -bench . $(TEST_PACKAGES_HOST) $(TEST_PACKAGES_SLOW)
+tinygo-bench-fast:
+	$(TINYGO) test -bench . $(TEST_PACKAGES_HOST)
+
+# Same thing, except for wasi rather than the current platform.
+tinygo-test-wasi:
+	$(TINYGO) test -target wasi $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_SLOW)
+tinygo-test-wasi-fast:
+	$(TINYGO) test -target wasi $(TEST_PACKAGES_FAST)
+tinygo-bench-wasi:
+	$(TINYGO) test -target wasi -bench . $(TEST_PACKAGES_FAST) $(TEST_PACKAGES_SLOW)
+tinygo-bench-wasi-fast:
+	$(TINYGO) test -target wasi -bench . $(TEST_PACKAGES_FAST)
+
+# Test external packages in a large corpus.
+test-corpus:
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=1h -buildmode exe -tags byollvm -run TestCorpus . -corpus=testdata/corpus.yaml
+test-corpus-fast:
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=1h -buildmode exe -tags byollvm -run TestCorpus -short . -corpus=testdata/corpus.yaml
+test-corpus-wasi: wasi-libc
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=1h -buildmode exe -tags byollvm -run TestCorpus . -corpus=testdata/corpus.yaml -target=wasi
+
+tinygo-baremetal:
+	# Regression tests that run on a baremetal target and don't fit in either main_test.go or smoketest.
+	# regression test for #2666: e.g. encoding/hex must pass on baremetal
+	$(TINYGO) test -target cortex-m-qemu encoding/hex
 
 .PHONY: smoketest
 smoketest:
 	$(TINYGO) version
+	# regression test for #2892
+	cd tests/testing/recurse && ($(TINYGO) test ./... > recurse.log && cat recurse.log && test $$(wc -l < recurse.log) = 2 && rm recurse.log)
+	# compile-only platform-independent examples
+	cd tests/text/template/smoke && $(TINYGO) test -c && rm -f smoke.test
+	# regression test for #2563
+	cd tests/os/smoke && $(TINYGO) test -c -target=pybadge && rm smoke.test
 	# test all examples (except pwm)
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/blinky1
 	@$(MD5SUM) test.hex
@@ -220,13 +398,15 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/echo
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/echo2
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=circuitplay-express examples/i2s
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/mcp3008
 	@$(MD5SUM) test.hex
-	$(TINYGO) build -size short -o test.hex -target=microbit            examples/microbit-blink
+	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/memstats
 	@$(MD5SUM) test.hex
-	$(TINYGO) build -size short -o test.hex -target=microbit-v2         examples/microbit-blink
+	$(TINYGO) build -size short -o test.hex -target=microbit            examples/microbit-blink
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/pininterrupt
 	@$(MD5SUM) test.hex
@@ -236,19 +416,27 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/test
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=wioterminal         examples/hid-mouse
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=wioterminal         examples/hid-keyboard
+	@$(MD5SUM) test.hex
 	# test simulated boards on play.tinygo.org
-	$(TINYGO) build             -o test.wasm -tags=arduino              examples/blinky1
+ifneq ($(WASM), 0)
+	$(TINYGO) build -size short -o test.wasm -tags=arduino              examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build             -o test.wasm -tags=hifive1b             examples/blinky1
+	$(TINYGO) build -size short -o test.wasm -tags=hifive1b             examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build             -o test.wasm -tags=reelboard            examples/blinky1
+	$(TINYGO) build -size short -o test.wasm -tags=reelboard            examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build             -o test.wasm -tags=pca10040             examples/blinky2
+	$(TINYGO) build -size short -o test.wasm -tags=pca10040             examples/blinky2
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build             -o test.wasm -tags=pca10056             examples/blinky2
+	$(TINYGO) build -size short -o test.wasm -tags=pca10056             examples/blinky2
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build             -o test.wasm -tags=circuitplay_express  examples/blinky1
+	$(TINYGO) build -size short -o test.wasm -tags=circuitplay_express  examples/blinky1
 	@$(MD5SUM) test.wasm
+	$(TINYGO) build -size short -o test.wasm -tags=circuitplay_bluefruit examples/blinky1
+	@$(MD5SUM) test.wasm
+endif
 	# test all targets/boards
 	$(TINYGO) build -size short -o test.hex -target=pca10040-s132v6     examples/blinky1
 	@$(MD5SUM) test.hex
@@ -256,6 +444,10 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=microbit-s110v8     examples/echo
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=microbit-v2         examples/microbit-blink
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=microbit-v2-s113v7  examples/microbit-blink
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=nrf52840-mdk        examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10031            examples/blinky1
@@ -288,6 +480,8 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.gba -target=gameboy-advance     examples/gba-display
 	@$(MD5SUM) test.gba
+	$(TINYGO) build -size short -o test.hex -target=grandcentral-m4     examples/blinky1
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-m4        examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=feather-m4          examples/blinky1
@@ -324,9 +518,13 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=feather-nrf52840  	examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=feather-nrf52840-sense examples/blinky1
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-nrf52840  examples/blinky1
 	@$(MD5SUM) test.hex
-	$(TINYGO) build -size short -o test.hex -target=qtpy  				examples/blinky1
+	$(TINYGO) build -size short -o test.hex -target=qtpy                examples/serial
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=teensy41            examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=teensy40            examples/blinky1
 	@$(MD5SUM) test.hex
@@ -334,6 +532,28 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=p1am-100            examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=atsame54-xpro       examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=atsame54-xpro       examples/can
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=feather-m4-can      examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=feather-m4-can      examples/caninterrupt
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=arduino-nano33      examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=arduino-mkrwifi1010 examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=pico                examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=nano-33-ble         examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=nano-rp2040         examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=feather-rp2040 		examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=macropad-rp2040 	examples/blinky1
+	@$(MD5SUM) test.hex
 	# test pwm
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-m0        examples/pwm
 	@$(MD5SUM) test.hex
@@ -341,7 +561,10 @@ smoketest:
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=feather-m4          examples/pwm
 	@$(MD5SUM) test.hex
-	$(TINYGO) build -size short -o test.hex -target=pyportal            examples/pwm
+	# test usbhid
+	$(TINYGO) build -size short -o test.hex -target=feather-nrf52840    examples/hid-keyboard
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=circuitplay-express examples/hid-keyboard
 	@$(MD5SUM) test.hex
 ifneq ($(STM32), 0)
 	$(TINYGO) build -size short -o test.hex -target=bluepill            examples/blinky1
@@ -354,16 +577,28 @@ ifneq ($(STM32), 0)
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=nucleo-f722ze       examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=nucleo-l031k6       examples/blinky1
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=nucleo-l432kc       examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=nucleo-l552ze       examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=nucleo-wl55jc       examples/blinky1
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=stm32f4disco        examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=stm32f4disco        examples/blinky2
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=stm32f4disco-1      examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=stm32f4disco-1      examples/pwm
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=stm32f469disco      examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=lorae5              examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=swan                examples/blinky1
+	@$(MD5SUM) test.hex
 endif
 ifneq ($(AVR), 0)
 	$(TINYGO) build -size short -o test.hex -target=atmega1284p         examples/serial
@@ -374,6 +609,10 @@ ifneq ($(AVR), 0)
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=arduino -scheduler=tasks  examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=arduino-mega1280    examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=arduino-mega1280    examples/pwm
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=arduino-nano        examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=digispark           examples/blinky1
@@ -386,71 +625,134 @@ ifneq ($(XTENSA), 0)
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=nodemcu             examples/blinky1
 	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target m5stack-core2       examples/serial
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target m5stack             examples/serial
+	@$(MD5SUM) test.bin
 endif
+	$(TINYGO) build -size short -o test.bin -target=esp32c3           	examples/serial
+	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=m5stamp-c3          examples/serial
+	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.hex -target=hifive1b            examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=hifive1-qemu        examples/serial
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=maixbit             examples/blinky1
 	@$(MD5SUM) test.hex
-	$(TINYGO) build             -o wasm.wasm -target=wasm               examples/wasm/export
-	$(TINYGO) build             -o wasm.wasm -target=wasm               examples/wasm/main
+ifneq ($(WASM), 0)
+	$(TINYGO) build -size short -o wasm.wasm -target=wasm               examples/wasm/export
+	$(TINYGO) build -size short -o wasm.wasm -target=wasm               examples/wasm/main
+endif
 	# test various compiler flags
 	$(TINYGO) build -size short -o test.hex -target=pca10040 -gc=none -scheduler=none examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040 -opt=1     examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=pca10040 -serial=none examples/echo
+	@$(MD5SUM) test.hex
 	$(TINYGO) build             -o test.nro -target=nintendoswitch      examples/serial
 	@$(MD5SUM) test.nro
 	$(TINYGO) build -size short -o test.hex -target=pca10040 -opt=0     ./testdata/stdlib.go
 	@$(MD5SUM) test.hex
+	GOOS=linux GOARCH=arm $(TINYGO) build -size short -o test.elf       ./testdata/cgo
+	GOOS=windows GOARCH=amd64 $(TINYGO) build -size short -o test.exe   ./testdata/cgo
+	GOOS=darwin GOARCH=amd64 $(TINYGO) build  -size short -o test       ./testdata/cgo
+	GOOS=darwin GOARCH=arm64 $(TINYGO) build  -size short -o test       ./testdata/cgo
+ifneq ($(OS),Windows_NT)
+	# TODO: this does not yet work on Windows. Somehow, unused functions are
+	# not garbage collected.
+	$(TINYGO) build -o test.elf -gc=leaking -scheduler=none examples/serial
+endif
 
 
 wasmtest:
 	$(GO) test ./tests/wasm
 
-build/release: tinygo gen-device wasi-libc
+build/release: tinygo gen-device wasi-libc $(if $(filter 1,$(USE_SYSTEM_BINARYEN)),,binaryen)
 	@mkdir -p build/release/tinygo/bin
 	@mkdir -p build/release/tinygo/lib/clang/include
 	@mkdir -p build/release/tinygo/lib/CMSIS/CMSIS
-	@mkdir -p build/release/tinygo/lib/compiler-rt/lib
+	@mkdir -p build/release/tinygo/lib/macos-minimal-sdk
+	@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
+	@mkdir -p build/release/tinygo/lib/mingw-w64/mingw-w64-headers/defaults
+	@mkdir -p build/release/tinygo/lib/musl/arch
+	@mkdir -p build/release/tinygo/lib/musl/crt
+	@mkdir -p build/release/tinygo/lib/musl/src
 	@mkdir -p build/release/tinygo/lib/nrfx
 	@mkdir -p build/release/tinygo/lib/picolibc/newlib/libc
+	@mkdir -p build/release/tinygo/lib/picolibc/newlib/libm
 	@mkdir -p build/release/tinygo/lib/wasi-libc
-	@mkdir -p build/release/tinygo/pkg/armv6m-none-eabi
-	@mkdir -p build/release/tinygo/pkg/armv7m-none-eabi
-	@mkdir -p build/release/tinygo/pkg/armv7em-none-eabi
+	@mkdir -p build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0
+	@mkdir -p build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0plus
+	@mkdir -p build/release/tinygo/pkg/thumbv7em-unknown-unknown-eabi-cortex-m4
 	@echo copying source files
 	@cp -p  build/tinygo$(EXE)           build/release/tinygo/bin
+ifneq ($(USE_SYSTEM_BINARYEN),1)
+	@cp -p  build/wasm-opt$(EXE)         build/release/tinygo/bin
+endif
 	@cp -p $(abspath $(CLANG_SRC))/lib/Headers/*.h build/release/tinygo/lib/clang/include
 	@cp -rp lib/CMSIS/CMSIS/Include      build/release/tinygo/lib/CMSIS/CMSIS
 	@cp -rp lib/CMSIS/README.md          build/release/tinygo/lib/CMSIS
-	@cp -rp lib/compiler-rt/lib/builtins build/release/tinygo/lib/compiler-rt/lib
-	@cp -rp lib/compiler-rt/LICENSE.TXT  build/release/tinygo/lib/compiler-rt
-	@cp -rp lib/compiler-rt/README.txt   build/release/tinygo/lib/compiler-rt
+	@cp -rp lib/macos-minimal-sdk/*      build/release/tinygo/lib/macos-minimal-sdk
+	@cp -rp lib/musl/arch/aarch64        build/release/tinygo/lib/musl/arch
+	@cp -rp lib/musl/arch/arm            build/release/tinygo/lib/musl/arch
+	@cp -rp lib/musl/arch/generic        build/release/tinygo/lib/musl/arch
+	@cp -rp lib/musl/arch/i386           build/release/tinygo/lib/musl/arch
+	@cp -rp lib/musl/arch/x86_64         build/release/tinygo/lib/musl/arch
+	@cp -rp lib/musl/crt/crt1.c          build/release/tinygo/lib/musl/crt
+	@cp -rp lib/musl/COPYRIGHT           build/release/tinygo/lib/musl
+	@cp -rp lib/musl/include             build/release/tinygo/lib/musl
+	@cp -rp lib/musl/src/env             build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/errno           build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/exit            build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/include         build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/internal        build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/malloc          build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/mman            build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/signal          build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/stdio           build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/string          build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/thread          build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/time            build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/unistd          build/release/tinygo/lib/musl/src
+	@cp -rp lib/mingw-w64/mingw-w64-crt/def-include                 build/release/tinygo/lib/mingw-w64/mingw-w64-crt
+	@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/api-ms-win-crt-* build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
+	@cp -rp lib/mingw-w64/mingw-w64-crt/lib-common/kernel32.def.in  build/release/tinygo/lib/mingw-w64/mingw-w64-crt/lib-common
+	@cp -rp lib/mingw-w64/mingw-w64-headers/crt/                    build/release/tinygo/lib/mingw-w64/mingw-w64-headers
+	@cp -rp lib/mingw-w64/mingw-w64-headers/defaults/include        build/release/tinygo/lib/mingw-w64/mingw-w64-headers/defaults
 	@cp -rp lib/nrfx/*                   build/release/tinygo/lib/nrfx
 	@cp -rp lib/picolibc/newlib/libc/ctype       build/release/tinygo/lib/picolibc/newlib/libc
 	@cp -rp lib/picolibc/newlib/libc/include     build/release/tinygo/lib/picolibc/newlib/libc
 	@cp -rp lib/picolibc/newlib/libc/locale      build/release/tinygo/lib/picolibc/newlib/libc
 	@cp -rp lib/picolibc/newlib/libc/string      build/release/tinygo/lib/picolibc/newlib/libc
 	@cp -rp lib/picolibc/newlib/libc/tinystdio   build/release/tinygo/lib/picolibc/newlib/libc
-	@cp -rp lib/picolibc-include         build/release/tinygo/lib
+	@cp -rp lib/picolibc/newlib/libm/common      build/release/tinygo/lib/picolibc/newlib/libm
+	@cp -rp lib/picolibc-stdio.c         build/release/tinygo/lib
 	@cp -rp lib/wasi-libc/sysroot        build/release/tinygo/lib/wasi-libc/sysroot
+	@cp -rp llvm-project/compiler-rt/lib/builtins build/release/tinygo/lib/compiler-rt-builtins
+	@cp -rp llvm-project/compiler-rt/LICENSE.TXT  build/release/tinygo/lib/compiler-rt-builtins
 	@cp -rp src                          build/release/tinygo/src
 	@cp -rp targets                      build/release/tinygo/targets
-	./build/tinygo build-library -target=armv6m-none-eabi  -o build/release/tinygo/pkg/armv6m-none-eabi/compiler-rt.a compiler-rt
-	./build/tinygo build-library -target=armv7m-none-eabi  -o build/release/tinygo/pkg/armv7m-none-eabi/compiler-rt.a compiler-rt
-	./build/tinygo build-library -target=armv7em-none-eabi -o build/release/tinygo/pkg/armv7em-none-eabi/compiler-rt.a compiler-rt
-	./build/tinygo build-library -target=armv6m-none-eabi  -o build/release/tinygo/pkg/armv6m-none-eabi/picolibc.a picolibc
-	./build/tinygo build-library -target=armv7m-none-eabi  -o build/release/tinygo/pkg/armv7m-none-eabi/picolibc.a picolibc
-	./build/tinygo build-library -target=armv7em-none-eabi -o build/release/tinygo/pkg/armv7em-none-eabi/picolibc.a picolibc
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m0     -o build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0/compiler-rt     compiler-rt
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m0plus -o build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0plus/compiler-rt compiler-rt
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m4     -o build/release/tinygo/pkg/thumbv7em-unknown-unknown-eabi-cortex-m4/compiler-rt    compiler-rt
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m0     -o build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0/picolibc     picolibc
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m0plus -o build/release/tinygo/pkg/thumbv6m-unknown-unknown-eabi-cortex-m0plus/picolibc picolibc
+	./build/release/tinygo/bin/tinygo build-library -target=cortex-m4     -o build/release/tinygo/pkg/thumbv7em-unknown-unknown-eabi-cortex-m4/picolibc    picolibc
 
-release: build/release
+release:
 	tar -czf build/release.tar.gz -C build/release tinygo
 
-deb: build/release
+DEB_ARCH ?= native
+deb:
 	@mkdir -p build/release-deb/usr/local/bin
 	@mkdir -p build/release-deb/usr/local/lib
 	cp -ar build/release/tinygo build/release-deb/usr/local/lib/tinygo
 	ln -sf ../lib/tinygo/bin/tinygo build/release-deb/usr/local/bin/tinygo
-	fpm -f -s dir -t deb -n tinygo -v $(shell grep "const Version = " goenv/version.go | awk '{print $$NF}') -m '@tinygo-org' --description='TinyGo is a Go compiler for small places.' --license='BSD 3-Clause' --url=https://tinygo.org/ --deb-changelog CHANGELOG.md -p build/release.deb -C ./build/release-deb
+	fpm -f -s dir -t deb -n tinygo -a $(DEB_ARCH) -v $(shell grep "const Version = " goenv/version.go | awk '{print $$NF}') -m '@tinygo-org' --description='TinyGo is a Go compiler for small places.' --license='BSD 3-Clause' --url=https://tinygo.org/ --deb-changelog CHANGELOG.md -p build/release.deb -C ./build/release-deb
+
+ifneq ($(RELEASEONLY), 1)
+release: build/release
+deb: build/release
+endif

README.md

@@ -1,6 +1,6 @@
 # TinyGo - Go compiler for small places
 
-[![CircleCI](https://circleci.com/gh/tinygo-org/tinygo/tree/dev.svg?style=svg)](https://circleci.com/gh/tinygo-org/tinygo/tree/dev) [![Build Status](https://dev.azure.com/tinygo/tinygo/_apis/build/status/tinygo-CI?branchName=dev)](https://dev.azure.com/tinygo/tinygo/_build/latest?definitionId=1&branchName=dev)
+[![Linux](https://github.com/tinygo-org/tinygo/actions/workflows/linux.yml/badge.svg?branch=dev)](https://github.com/tinygo-org/tinygo/actions/workflows/linux.yml) [![macOS](https://github.com/tinygo-org/tinygo/actions/workflows/build-macos.yml/badge.svg?branch=dev)](https://github.com/tinygo-org/tinygo/actions/workflows/build-macos.yml) [![Windows](https://github.com/tinygo-org/tinygo/actions/workflows/windows.yml/badge.svg?branch=dev)](https://github.com/tinygo-org/tinygo/actions/workflows/windows.yml) [![Docker](https://github.com/tinygo-org/tinygo/actions/workflows/docker.yml/badge.svg?branch=dev)](https://github.com/tinygo-org/tinygo/actions/workflows/docker.yml) [![CircleCI](https://circleci.com/gh/tinygo-org/tinygo/tree/dev.svg?style=svg)](https://circleci.com/gh/tinygo-org/tinygo/tree/dev)
 
 TinyGo is a Go compiler intended for use in small places such as microcontrollers, WebAssembly (Wasm), and command-line tools.
 
@@ -43,18 +43,23 @@ See the [getting started instructions](https://tinygo.org/getting-started/) for
 
 You can compile TinyGo programs for microcontrollers, WebAssembly and Linux.
 
-The following 55 microcontroller boards are currently supported:
+The following 85 microcontroller boards are currently supported:
 
 * [Adafruit Circuit Playground Bluefruit](https://www.adafruit.com/product/4333)
 * [Adafruit Circuit Playground Express](https://www.adafruit.com/product/3333)
 * [Adafruit CLUE](https://www.adafruit.com/product/4500)
 * [Adafruit Feather M0](https://www.adafruit.com/product/2772)
 * [Adafruit Feather M4](https://www.adafruit.com/product/3857)
+* [Adafruit Feather M4 CAN](https://www.adafruit.com/product/4759)
 * [Adafruit Feather nRF52840 Express](https://www.adafruit.com/product/4062)
+* [Adafruit Feather nRF52840 Sense](https://www.adafruit.com/product/4516)
+* [Adafruit Feather RP2040](https://www.adafruit.com/product/4884)
 * [Adafruit Feather STM32F405 Express](https://www.adafruit.com/product/4382)
+* [Adafruit Grand Central M4](https://www.adafruit.com/product/4064)
 * [Adafruit ItsyBitsy M0](https://www.adafruit.com/product/3727)
 * [Adafruit ItsyBitsy M4](https://www.adafruit.com/product/3800)
 * [Adafruit ItsyBitsy nRF52840](https://www.adafruit.com/product/4481)
+* [Adafruit MacroPad RP2040](https://www.adafruit.com/product/5100)
 * [Adafruit Matrix Portal M4](https://www.adafruit.com/product/4745)
 * [Adafruit Metro M4 Express Airlift](https://www.adafruit.com/product/4000)
 * [Adafruit PyBadge](https://www.adafruit.com/product/4200)
@@ -62,26 +67,40 @@ The following 55 microcontroller boards are currently supported:
 * [Adafruit PyPortal](https://www.adafruit.com/product/4116)
 * [Adafruit QT Py](https://www.adafruit.com/product/4600)
 * [Adafruit Trinket M0](https://www.adafruit.com/product/3500)
+* [Arduino Mega 1280](https://www.arduino.cc/en/Main/arduinoBoardMega/)
 * [Arduino Mega 2560](https://store.arduino.cc/arduino-mega-2560-rev3)
 * [Arduino MKR1000](https://store.arduino.cc/arduino-mkr1000-wifi)
+* [Arduino MKR WiFi 1010](https://store.arduino.cc/usa/mkr-wifi-1010)
 * [Arduino Nano](https://store.arduino.cc/arduino-nano)
-* [Arduino Nano33 IoT](https://store.arduino.cc/nano-33-iot)
+* [Arduino Nano 33 BLE](https://store.arduino.cc/nano-33-ble)
+* [Arduino Nano 33 BLE Sense](https://store.arduino.cc/nano-33-ble-sense)
+* [Arduino Nano 33 IoT](https://store.arduino.cc/nano-33-iot)
+* [Arduino Nano RP2040 Connect](https://store.arduino.cc/nano-rp2040-connect)
 * [Arduino Uno](https://store.arduino.cc/arduino-uno-rev3)
 * [Arduino Zero](https://store.arduino.cc/usa/arduino-zero)
 * [BBC micro:bit](https://microbit.org/)
 * [BBC micro:bit v2](https://microbit.org/new-microbit/)
+* [blues wireless Swan](https://blues.io/products/swan/)
 * [Digispark](http://digistump.com/products/1)
 * [Dragino LoRaWAN GPS Tracker LGT-92](http://www.dragino.com/products/lora-lorawan-end-node/item/142-lgt-92.html)
-* [ESP32](https://www.espressif.com/en/products/socs/esp32)
-* [ESP8266](https://www.espressif.com/en/products/socs/esp8266)
+* [ESP32 - Core board](https://www.espressif.com/en/products/socs/esp32)
+* [ESP32 - mini32](https://www.espressif.com/en/products/socs/esp32)
+* [ESP32-C3-12f](https://www.espressif.com/en/products/socs/esp32-c3)
+* [ESP8266 - d1mini](https://www.espressif.com/en/products/socs/esp8266)
+* [ESP8266 - NodeMCU](https://www.espressif.com/en/products/socs/esp8266)
 * [Game Boy Advance](https://en.wikipedia.org/wiki/Game_Boy_Advance)
+* [M5Stack](https://docs.m5stack.com/en/core/basic)
+* [M5Stack Core2](https://shop.m5stack.com/products/m5stack-core2-esp32-iot-development-kit)
+* [M5Stamp C3](https://docs.m5stack.com/en/core/stamp_c3)
 * [Makerdiary nRF52840-MDK](https://wiki.makerdiary.com/nrf52840-mdk/)
 * [Makerdiary nRF52840-MDK USB Dongle](https://wiki.makerdiary.com/nrf52840-mdk-usb-dongle/)
+* [Microchip SAM E54 Xplained Pro](https://www.microchip.com/developmenttools/productdetails/atsame54-xpro)
 * [nice!nano](https://docs.nicekeyboards.com/#/nice!nano/)
 * [Nintendo Switch](https://www.nintendo.com/switch/)
 * [Nordic Semiconductor PCA10031](https://www.nordicsemi.com/eng/Products/nRF51-Dongle)
 * [Nordic Semiconductor PCA10040](https://www.nordicsemi.com/eng/Products/Bluetooth-low-energy/nRF52-DK)
 * [Nordic Semiconductor PCA10056](https://www.nordicsemi.com/Software-and-Tools/Development-Kits/nRF52840-DK)
+* [Nordic Semiconductor pca10059](https://www.nordicsemi.com/Software-and-tools/Development-Kits/nRF52840-Dongle)
 * [Particle Argon](https://docs.particle.io/datasheets/wi-fi/argon-datasheet/)
 * [Particle Boron](https://docs.particle.io/datasheets/cellular/boron-datasheet/)
 * [Particle Xenon](https://docs.particle.io/datasheets/discontinued/xenon-datasheet/)
@@ -89,17 +108,28 @@ The following 55 microcontroller boards are currently supported:
 * [PineTime DevKit](https://www.pine64.org/pinetime/)
 * [PJRC Teensy 3.6](https://www.pjrc.com/store/teensy36.html)
 * [PJRC Teensy 4.0](https://www.pjrc.com/store/teensy40.html)
+* [PJRC Teensy 4.1](https://www.pjrc.com/store/teensy41.html)
 * [ProductivityOpen P1AM-100](https://facts-engineering.github.io/modules/P1AM-100/P1AM-100.html)
-* [Seeed Wio Terminal](https://www.seeedstudio.com/Wio-Terminal-p-4509.html)
+* [Raspberry Pi Pico](https://www.raspberrypi.org/products/raspberry-pi-pico/)
+* [Raytac MDBT50Q-RX Dongle (with TinyUF2 bootloader)](https://www.adafruit.com/product/5199)
 * [Seeed Seeeduino XIAO](https://www.seeedstudio.com/Seeeduino-XIAO-Arduino-Microcontroller-SAMD21-Cortex-M0+-p-4426.html)
+* [Seeed XIAO BLE](https://www.seeedstudio.com/Seeed-XIAO-BLE-nRF52840-p-5201.html)
+* [Seeed LoRa-E5 Development Kit](https://www.seeedstudio.com/LoRa-E5-Dev-Kit-p-4868.html)
 * [Seeed Sipeed MAix BiT](https://www.seeedstudio.com/Sipeed-MAix-BiT-for-RISC-V-AI-IoT-p-2872.html)
-* [SiFIve HiFive1](https://www.sifive.com/boards/hifive1)
+* [Seeed Wio Terminal](https://www.seeedstudio.com/Wio-Terminal-p-4509.html)
+* [SiFIve HiFive1 Rev B](https://www.sifive.com/boards/hifive1)
+* [Sparkfun Thing Plus RP2040](https://www.sparkfun.com/products/17745)
 * [ST Micro "Nucleo" F103RB](https://www.st.com/en/evaluation-tools/nucleo-f103rb.html)
 * [ST Micro "Nucleo" F722ZE](https://www.st.com/en/evaluation-tools/nucleo-f722ze.html)
+* [ST Micro "Nucleo" L031K6](https://www.st.com/ja/evaluation-tools/nucleo-l031k6.html)
+* [ST Micro "Nucleo" L432KC](https://www.st.com/ja/evaluation-tools/nucleo-l432kc.html)
 * [ST Micro "Nucleo" L552ZE](https://www.st.com/en/evaluation-tools/nucleo-l552ze-q.html)
+* [ST Micro "Nucleo" WL55JC](https://www.st.com/en/evaluation-tools/nucleo-wl55jc.html)
 * [ST Micro STM32F103XX "Bluepill"](https://stm32-base.org/boards/STM32F103C8T6-Blue-Pill)
 * [ST Micro STM32F407 "Discovery"](https://www.st.com/en/evaluation-tools/stm32f4discovery.html)
+* [ST Micro STM32F469 "Discovery"](https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eval-tools/stm32-mcu-mpu-eval-tools/stm32-discovery-kits/32f469idiscovery.html)
 * [X9 Pro smartwatch](https://github.com/curtpw/nRF5x-device-reverse-engineering/tree/master/X9-nrf52832-activity-tracker/)
+* [The Things Industries Generic Node Sensor Edition](https://www.genericnode.com/docs/sensor-edition/)
 
 For more information, see [this list of boards](https://tinygo.org/microcontrollers/). Pull requests for additional support are welcome!
 
@@ -126,7 +156,7 @@ should arrive fairly quickly (under 1 min): https://invite.slack.golangbridge.or
 
 Your contributions are welcome!
 
-Please take a look at our [CONTRIBUTING.md](./CONTRIBUTING.md) document for details.
+Please take a look at our [Contributing](https://tinygo.org/docs/guides/contributing/) page on our web site for details.
 
 ## Project Scope
 
@@ -140,7 +170,6 @@ Goals:
 
 Non-goals:
 
-* Using more than one core.
 * Be efficient while using zillions of goroutines. However, good goroutine support is certainly a goal.
 * Be as fast as `gc`. However, LLVM will probably be better at optimizing certain things so TinyGo might actually turn out to be faster for number crunching.
 * Be able to compile every Go program out there.

azure-pipelines.yml

@@ -1,88 +0,0 @@
-# Avoid lengthy LLVM rebuilds on each newly pushed branch. Pull requests will
-# be built anyway.
-trigger:
-- release
-- dev
-
-jobs:
-- job: Build
-  timeoutInMinutes: 240 # 4h
-  pool:
-    vmImage: 'VS2017-Win2016'
-  steps:
-    - task: GoTool@0
-      inputs:
-        version: '1.16'
-    - checkout: self
-      fetchDepth: 1
-    - task: Cache@2
-      displayName: Cache LLVM source
-      inputs:
-        key: llvm-source-11-windows-v1
-        path: llvm-project
-    - task: Bash@3
-      displayName: Download LLVM source
-      inputs:
-        targetType: inline
-        script: make llvm-source
-    - task: CacheBeta@0
-      displayName: Cache LLVM build
-      inputs:
-        key: llvm-build-11-windows-v4
-        path: llvm-build
-    - task: Bash@3
-      displayName: Build LLVM
-      inputs:
-        targetType: inline
-        script: |
-          if [ ! -f llvm-build/lib/liblldELF.a ]
-          then
-            # install dependencies
-            choco install ninja
-            # hack ninja to use fewer jobs
-            echo -e 'C:\\ProgramData\\Chocolatey\\bin\\ninja -j4 %*' > /usr/bin/ninja.bat
-            # build!
-            make llvm-build
-          fi
-    - task: Bash@3
-      displayName: Install QEMU
-      inputs:
-        targetType: inline
-        script: choco install qemu --version=2020.06.12
-    - task: CacheBeta@0
-      displayName: Cache wasi-libc sysroot
-      inputs:
-        key: wasi-libc-sysroot-v4
-        path: lib/wasi-libc/sysroot
-    - task: Bash@3
-      displayName: Build wasi-libc
-      inputs:
-        targetType: inline
-        script: PATH=/usr/bin:$PATH make wasi-libc
-    - task: Bash@3
-      displayName: Test TinyGo
-      inputs:
-        targetType: inline
-        script: |
-          export PATH="$PATH:./llvm-build/bin:/c/Program Files/qemu"
-          unset GOROOT
-          make test
-    - task: Bash@3
-      displayName: Build TinyGo release tarball
-      inputs:
-        targetType: inline
-        script: |
-          export PATH="$PATH:./llvm-build/bin:/c/Program Files/qemu"
-          unset GOROOT
-          make build/release -j4
-    - publish: $(System.DefaultWorkingDirectory)/build/release/tinygo
-      displayName: Publish zip as artifact
-      artifact: tinygo
-    - task: Bash@3
-      displayName: Smoke tests
-      inputs:
-        targetType: inline
-        script: |
-          export PATH="$PATH:./llvm-build/bin:/c/Program Files/qemu"
-          unset GOROOT
-          make smoketest TINYGO=build/tinygo AVR=0 XTENSA=0

builder/ar.go

@@ -3,8 +3,10 @@ package builder
 import (
 	"bytes"
 	"debug/elf"
+	"debug/pe"
 	"encoding/binary"
 	"errors"
+	"fmt"
 	"io"
 	"os"
 	"path/filepath"
@@ -17,17 +19,12 @@ import (
 // given as a parameter. It is equivalent to the following command:
 //
 //     ar -rcs <archivePath> <objs...>
-func makeArchive(archivePath string, objs []string) error {
+func makeArchive(arfile *os.File, objs []string) error {
 	// Open the archive file.
-	arfile, err := os.Create(archivePath)
-	if err != nil {
-		return err
-	}
-	defer arfile.Close()
 	arwriter := ar.NewWriter(arfile)
-	err = arwriter.WriteGlobalHeader()
+	err := arwriter.WriteGlobalHeader()
 	if err != nil {
-		return &os.PathError{"write ar header", archivePath, err}
+		return &os.PathError{Op: "write ar header", Path: arfile.Name(), Err: err}
 	}
 
 	// Open all object files and read the symbols for the symbol table.
@@ -35,43 +32,55 @@ func makeArchive(archivePath string, objs []string) error {
 		name      string // symbol name
 		fileIndex int    // index into objfiles
 	}{}
-	objfiles := make([]struct {
-		file          *os.File
-		archiveOffset int32
-	}, len(objs))
+	archiveOffsets := make([]int32, len(objs))
 	for i, objpath := range objs {
 		objfile, err := os.Open(objpath)
 		if err != nil {
 			return err
 		}
-		objfiles[i].file = objfile
 
 		// Read the symbols and add them to the symbol table.
-		dbg, err := elf.NewFile(objfile)
-		if err != nil {
-			return err
-		}
-		symbols, err := dbg.Symbols()
-		if err != nil {
-			return err
-		}
-		for _, symbol := range symbols {
-			bind := elf.ST_BIND(symbol.Info)
-			if bind != elf.STB_GLOBAL && bind != elf.STB_WEAK {
-				// Don't include local symbols (STB_LOCAL).
-				continue
+		if dbg, err := elf.NewFile(objfile); err == nil {
+			symbols, err := dbg.Symbols()
+			if err != nil {
+				return err
 			}
-			if elf.ST_TYPE(symbol.Info) != elf.STT_FUNC {
-				// Not a function.
-				// TODO: perhaps globals variables should also be included?
-				continue
+			for _, symbol := range symbols {
+				bind := elf.ST_BIND(symbol.Info)
+				if bind != elf.STB_GLOBAL && bind != elf.STB_WEAK {
+					// Don't include local symbols (STB_LOCAL).
+					continue
+				}
+				if elf.ST_TYPE(symbol.Info) != elf.STT_FUNC && elf.ST_TYPE(symbol.Info) != elf.STT_OBJECT {
+					// Not a function.
+					continue
+				}
+				// Include in archive.
+				symbolTable = append(symbolTable, struct {
+					name      string
+					fileIndex int
+				}{symbol.Name, i})
 			}
-			// Include in archive.
-			symbolTable = append(symbolTable, struct {
-				name      string
-				fileIndex int
-			}{symbol.Name, i})
+		} else if dbg, err := pe.NewFile(objfile); err == nil {
+			for _, symbol := range dbg.Symbols {
+				if symbol.StorageClass != 2 {
+					continue
+				}
+				if symbol.SectionNumber == 0 {
+					continue
+				}
+				symbolTable = append(symbolTable, struct {
+					name      string
+					fileIndex int
+				}{symbol.Name, i})
+			}
+		} else {
+			return fmt.Errorf("failed to open file %s as ELF or PE/COFF: %w", objpath, err)
 		}
+
+		// Close file, to avoid issues with too many open files (especially on
+		// MacOS X).
+		objfile.Close()
 	}
 
 	// Create the symbol table buffer.
@@ -125,7 +134,14 @@ func makeArchive(archivePath string, objs []string) error {
 	}
 
 	// Add all object files to the archive.
-	for i, objfile := range objfiles {
+	var copyBuf bytes.Buffer
+	for i, objpath := range objs {
+		objfile, err := os.Open(objpath)
+		if err != nil {
+			return err
+		}
+		defer objfile.Close()
+
 		// Store the start index, for when we'll update the symbol table with
 		// the correct file start indices.
 		offset, err := arfile.Seek(0, os.SEEK_CUR)
@@ -133,17 +149,17 @@ func makeArchive(archivePath string, objs []string) error {
 			return err
 		}
 		if int64(int32(offset)) != offset {
-			return errors.New("large archives (4GB+) not supported: " + archivePath)
+			return errors.New("large archives (4GB+) not supported: " + arfile.Name())
 		}
-		objfiles[i].archiveOffset = int32(offset)
+		archiveOffsets[i] = int32(offset)
 
 		// Write the file header.
-		st, err := objfile.file.Stat()
+		st, err := objfile.Stat()
 		if err != nil {
 			return err
 		}
 		err = arwriter.WriteHeader(&ar.Header{
-			Name:    filepath.Base(objfile.file.Name()),
+			Name:    filepath.Base(objfile.Name()),
 			ModTime: time.Unix(0, 0),
 			Uid:     0,
 			Gid:     0,
@@ -155,22 +171,30 @@ func makeArchive(archivePath string, objs []string) error {
 		}
 
 		// Copy the file contents into the archive.
-		n, err := io.Copy(arwriter, objfile.file)
+		// First load all contents into a buffer, then write it all in one go to
+		// the archive file. This is a bit complicated, but is necessary because
+		// io.Copy can't deal with files that are of an odd size.
+		copyBuf.Reset()
+		n, err := io.Copy(&copyBuf, objfile)
 		if err != nil {
-			return err
+			return fmt.Errorf("could not copy object file into ar file: %w", err)
 		}
 		if n != st.Size() {
-			return errors.New("file modified during ar creation: " + archivePath)
+			return errors.New("file modified during ar creation: " + arfile.Name())
+		}
+		_, err = arwriter.Write(copyBuf.Bytes())
+		if err != nil {
+			return fmt.Errorf("could not copy object file into ar file: %w", err)
 		}
 
 		// File is not needed anymore.
-		objfile.file.Close()
+		objfile.Close()
 	}
 
 	// Create symbol indices.
 	indicesBuf := &bytes.Buffer{}
 	for _, sym := range symbolTable {
-		err = binary.Write(indicesBuf, binary.BigEndian, objfiles[sym.fileIndex].archiveOffset)
+		err = binary.Write(indicesBuf, binary.BigEndian, archiveOffsets[sym.fileIndex])
 		if err != nil {
 			return err
 		}

builder/buildcache.go

@@ -1,105 +0,0 @@
-package builder
-
-import (
-	"io"
-	"os"
-	"path/filepath"
-	"time"
-
-	"github.com/tinygo-org/tinygo/goenv"
-)
-
-// Return the newest timestamp of all the file paths passed in. Used to check
-// for stale caches.
-func cacheTimestamp(paths []string) (time.Time, error) {
-	var timestamp time.Time
-	for _, path := range paths {
-		st, err := os.Stat(path)
-		if err != nil {
-			return time.Time{}, err
-		}
-		if timestamp.IsZero() {
-			timestamp = st.ModTime()
-		} else if timestamp.Before(st.ModTime()) {
-			timestamp = st.ModTime()
-		}
-	}
-	return timestamp, nil
-}
-
-// Try to load a given file from the cache. Return "", nil if no cached file can
-// be found (or the file is stale), return the absolute path if there is a cache
-// and return an error on I/O errors.
-func cacheLoad(name string, sourceFiles []string) (string, error) {
-	cachepath := filepath.Join(goenv.Get("GOCACHE"), name)
-	cacheStat, err := os.Stat(cachepath)
-	if os.IsNotExist(err) {
-		return "", nil // does not exist
-	} else if err != nil {
-		return "", err // cannot stat cache file
-	}
-
-	sourceTimestamp, err := cacheTimestamp(sourceFiles)
-	if err != nil {
-		return "", err // cannot stat source files
-	}
-
-	if cacheStat.ModTime().After(sourceTimestamp) {
-		return cachepath, nil
-	} else {
-		os.Remove(cachepath)
-		// stale cache
-		return "", nil
-	}
-}
-
-// Store the file located at tmppath in the cache with the given name. The
-// tmppath may or may not be gone afterwards.
-func cacheStore(tmppath, name string, sourceFiles []string) (string, error) {
-	// get the last modified time
-	if len(sourceFiles) == 0 {
-		panic("cache: no source files")
-	}
-
-	// TODO: check the config key
-
-	dir := goenv.Get("GOCACHE")
-	err := os.MkdirAll(dir, 0777)
-	if err != nil {
-		return "", err
-	}
-	cachepath := filepath.Join(dir, name)
-	err = copyFile(tmppath, cachepath)
-	if err != nil {
-		return "", err
-	}
-	return cachepath, nil
-}
-
-// copyFile copies the given file from src to dst. It can copy over
-// a possibly already existing file at the destination.
-func copyFile(src, dst string) error {
-	inf, err := os.Open(src)
-	if err != nil {
-		return err
-	}
-	defer inf.Close()
-	outpath := dst + ".tmp"
-	outf, err := os.Create(outpath)
-	if err != nil {
-		return err
-	}
-
-	_, err = io.Copy(outf, inf)
-	if err != nil {
-		os.Remove(outpath)
-		return err
-	}
-
-	err = outf.Close()
-	if err != nil {
-		return err
-	}
-
-	return os.Rename(dst+".tmp", dst)
-}

builder/builder_test.go

@@ -0,0 +1,168 @@
+package builder
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/goenv"
+	"tinygo.org/x/go-llvm"
+)
+
+// Test whether the Clang generated "target-cpu" and "target-features"
+// attributes match the CPU and Features property in TinyGo target files.
+func TestClangAttributes(t *testing.T) {
+	var targetNames = []string{
+		// Please keep this list sorted!
+		"atmega328p",
+		"atmega1280",
+		"atmega1284p",
+		"atmega2560",
+		"attiny85",
+		"cortex-m0",
+		"cortex-m0plus",
+		"cortex-m3",
+		"cortex-m33",
+		"cortex-m4",
+		"cortex-m7",
+		"esp32c3",
+		"fe310",
+		"gameboy-advance",
+		"k210",
+		"nintendoswitch",
+		"riscv-qemu",
+		"wasi",
+		"wasm",
+	}
+	if hasBuiltinTools {
+		// hasBuiltinTools is set when TinyGo is statically linked with LLVM,
+		// which also implies it was built with Xtensa support.
+		targetNames = append(targetNames, "esp32", "esp8266")
+	}
+	for _, targetName := range targetNames {
+		targetName := targetName
+		t.Run(targetName, func(t *testing.T) {
+			testClangAttributes(t, &compileopts.Options{Target: targetName})
+		})
+	}
+
+	for _, options := range []*compileopts.Options{
+		{GOOS: "linux", GOARCH: "386"},
+		{GOOS: "linux", GOARCH: "amd64"},
+		{GOOS: "linux", GOARCH: "arm", GOARM: "5"},
+		{GOOS: "linux", GOARCH: "arm", GOARM: "6"},
+		{GOOS: "linux", GOARCH: "arm", GOARM: "7"},
+		{GOOS: "linux", GOARCH: "arm64"},
+		{GOOS: "darwin", GOARCH: "amd64"},
+		{GOOS: "darwin", GOARCH: "arm64"},
+		{GOOS: "windows", GOARCH: "amd64"},
+	} {
+		name := "GOOS=" + options.GOOS + ",GOARCH=" + options.GOARCH
+		if options.GOARCH == "arm" {
+			name += ",GOARM=" + options.GOARM
+		}
+		t.Run(name, func(t *testing.T) {
+			testClangAttributes(t, options)
+		})
+	}
+}
+
+func testClangAttributes(t *testing.T, options *compileopts.Options) {
+	testDir := t.TempDir()
+	clangHeaderPath := getClangHeaderPath(goenv.Get("TINYGOROOT"))
+
+	ctx := llvm.NewContext()
+	defer ctx.Dispose()
+
+	target, err := compileopts.LoadTarget(options)
+	if err != nil {
+		t.Fatalf("could not load target: %s", err)
+	}
+	config := compileopts.Config{
+		Options:      options,
+		Target:       target,
+		ClangHeaders: clangHeaderPath,
+	}
+
+	// Create a very simple C input file.
+	srcpath := filepath.Join(testDir, "test.c")
+	err = ioutil.WriteFile(srcpath, []byte("int add(int a, int b) { return a + b; }"), 0o666)
+	if err != nil {
+		t.Fatalf("could not write target file %s: %s", srcpath, err)
+	}
+
+	// Compile this file using Clang.
+	outpath := filepath.Join(testDir, "test.bc")
+	flags := append([]string{"-c", "-emit-llvm", "-o", outpath, srcpath}, config.CFlags()...)
+	if config.GOOS() == "darwin" {
+		// Silence some warnings that happen when testing GOOS=darwin on
+		// something other than MacOS.
+		flags = append(flags, "-Wno-missing-sysroot", "-Wno-incompatible-sysroot")
+	}
+	err = runCCompiler(flags...)
+	if err != nil {
+		t.Fatalf("failed to compile %s: %s", srcpath, err)
+	}
+
+	// Read the resulting LLVM bitcode.
+	mod, err := ctx.ParseBitcodeFile(outpath)
+	if err != nil {
+		t.Fatalf("could not parse bitcode file %s: %s", outpath, err)
+	}
+	defer mod.Dispose()
+
+	// Check whether the LLVM target matches.
+	if mod.Target() != config.Triple() {
+		t.Errorf("target has LLVM triple %#v but Clang makes it LLVM triple %#v", config.Triple(), mod.Target())
+	}
+
+	// Check the "target-cpu" and "target-features" string attribute of the add
+	// function.
+	add := mod.NamedFunction("add")
+	var cpu, features string
+	cpuAttr := add.GetStringAttributeAtIndex(-1, "target-cpu")
+	featuresAttr := add.GetStringAttributeAtIndex(-1, "target-features")
+	if !cpuAttr.IsNil() {
+		cpu = cpuAttr.GetStringValue()
+	}
+	if !featuresAttr.IsNil() {
+		features = featuresAttr.GetStringValue()
+	}
+	if cpu != config.CPU() {
+		t.Errorf("target has CPU %#v but Clang makes it CPU %#v", config.CPU(), cpu)
+	}
+	if features != config.Features() {
+		if hasBuiltinTools || runtime.GOOS != "linux" {
+			// Skip this step when using an external Clang invocation on Linux.
+			// The reason is that Debian has patched Clang in a way that
+			// modifies the LLVM features string, changing lots of FPU/float
+			// related flags. We want to test vanilla Clang, not Debian Clang.
+			t.Errorf("target has LLVM features\n\t%#v\nbut Clang makes it\n\t%#v", config.Features(), features)
+		}
+	}
+}
+
+// This TestMain is necessary because TinyGo may also be invoked to run certain
+// LLVM tools in a separate process. Not capturing these invocations would lead
+// to recursive tests.
+func TestMain(m *testing.M) {
+	if len(os.Args) >= 2 {
+		switch os.Args[1] {
+		case "clang", "ld.lld", "wasm-ld":
+			// Invoke a specific tool.
+			err := RunTool(os.Args[1], os.Args[2:]...)
+			if err != nil {
+				fmt.Fprintln(os.Stderr, err)
+				os.Exit(1)
+			}
+			os.Exit(0)
+		}
+	}
+
+	// Run normal tests.
+	os.Exit(m.Run())
+}

builder/buildid.go

@@ -0,0 +1,103 @@
+package builder
+
+import (
+	"bytes"
+	"debug/elf"
+	"debug/macho"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"os"
+	"runtime"
+)
+
+// ReadBuildID reads the build ID from the currently running executable.
+func ReadBuildID() ([]byte, error) {
+	executable, err := os.Executable()
+	if err != nil {
+		return nil, err
+	}
+	f, err := os.Open(executable)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	switch runtime.GOOS {
+	case "linux", "freebsd":
+		// Read the GNU build id section. (Not sure about FreeBSD though...)
+		file, err := elf.NewFile(f)
+		if err != nil {
+			return nil, err
+		}
+		var gnuID, goID []byte
+		for _, section := range file.Sections {
+			if section.Type != elf.SHT_NOTE ||
+				(section.Name != ".note.gnu.build-id" && section.Name != ".note.go.buildid") {
+				continue
+			}
+			buf := make([]byte, section.Size)
+			n, err := section.ReadAt(buf, 0)
+			if uint64(n) != section.Size || err != nil {
+				return nil, fmt.Errorf("could not read build id: %w", err)
+			}
+			if section.Name == ".note.gnu.build-id" {
+				gnuID = buf
+			} else {
+				goID = buf
+			}
+		}
+		if gnuID != nil {
+			return gnuID, nil
+		} else if goID != nil {
+			return goID, nil
+		}
+	case "darwin":
+		// Read the LC_UUID load command, which contains the equivalent of a
+		// build ID.
+		file, err := macho.NewFile(f)
+		if err != nil {
+			return nil, err
+		}
+		for _, load := range file.Loads {
+			// Unfortunately, the debug/macho package doesn't support the
+			// LC_UUID command directly. So we have to read it from
+			// macho.LoadBytes.
+			load, ok := load.(macho.LoadBytes)
+			if !ok {
+				continue
+			}
+			raw := load.Raw()
+			command := binary.LittleEndian.Uint32(raw)
+			if command != 0x1b {
+				// Looking for the LC_UUID load command.
+				// LC_UUID is defined here as 0x1b:
+				// https://opensource.apple.com/source/xnu/xnu-4570.71.2/EXTERNAL_HEADERS/mach-o/loader.h.auto.html
+				continue
+			}
+			return raw[4:], nil
+		}
+	default:
+		// On other platforms (such as Windows) there isn't such a convenient
+		// build ID. Luckily, Go does have an equivalent of the build ID, which
+		// is stored as a special symbol named go.buildid. You can read it
+		// using `go tool buildid`, but the code below extracts it directly
+		// from the binary.
+		// Unfortunately, because of stripping with the -w flag, no symbol
+		// table might be available. Therefore, we have to scan the binary
+		// directly. Luckily the build ID is always at the start of the file.
+		// For details, see:
+		// https://github.com/golang/go/blob/master/src/cmd/internal/buildid/buildid.go
+		fileStart := make([]byte, 4096)
+		_, err := io.ReadFull(f, fileStart)
+		index := bytes.Index(fileStart, []byte("\xff Go build ID: \""))
+		if index < 0 || index > len(fileStart)-103 {
+			return nil, fmt.Errorf("could not find build id in %s", err)
+		}
+		buf := fileStart[index : index+103]
+		if bytes.HasPrefix(buf, []byte("\xff Go build ID: \"")) && bytes.HasSuffix(buf, []byte("\"\n \xff")) {
+			return buf[len("\xff Go build ID: \"") : len(buf)-1], nil
+		}
+	}
+	return nil, fmt.Errorf("could not find build ID in %s", executable)
+}

builder/builtins.go

@@ -1,7 +1,11 @@
 package builder
 
 import (
+	"os"
+	"path/filepath"
 	"strings"
+
+	"github.com/tinygo-org/tinygo/goenv"
 )
 
 // These are the GENERIC_SOURCES according to CMakeList.txt.
@@ -36,7 +40,6 @@ var genericBuiltins = []string{
 	"divdf3.c",
 	"divdi3.c",
 	"divmoddi4.c",
-	"divmodsi4.c",
 	"divsc3.c",
 	"divsf3.c",
 	"divsi3.c",
@@ -72,6 +75,7 @@ var genericBuiltins = []string{
 	"floatunsisf.c",
 	"floatuntidf.c",
 	"floatuntisf.c",
+	"fp_mode.c",
 	//"int_util.c",
 	"lshrdi3.c",
 	"lshrti3.c",
@@ -122,7 +126,6 @@ var genericBuiltins = []string{
 	"ucmpti2.c",
 	"udivdi3.c",
 	"udivmoddi4.c",
-	"udivmodsi4.c",
 	"udivmodti4.c",
 	"udivsi3.c",
 	"udivti3.c",
@@ -149,6 +152,14 @@ var aeabiBuiltins = []string{
 	"arm/aeabi_memset.S",
 	"arm/aeabi_uidivmod.S",
 	"arm/aeabi_uldivmod.S",
+
+	// These two are not technically EABI builtins but are used by them and only
+	// seem to be used on ARM. LLVM seems to use __divsi3 and __modsi3 on most
+	// other architectures.
+	// Most importantly, they have a different calling convention on AVR so
+	// should not be used on AVR.
+	"divmodsi4.c",
+	"udivmodsi4.c",
 }
 
 // CompilerRT is a library with symbols required by programs compiled with LLVM.
@@ -157,10 +168,20 @@ var aeabiBuiltins = []string{
 //
 // For more information, see: https://compiler-rt.llvm.org/
 var CompilerRT = Library{
-	name:      "compiler-rt",
-	cflags:    func() []string { return []string{"-Werror", "-Wall", "-std=c11", "-nostdlibinc"} },
-	sourceDir: "lib/compiler-rt/lib/builtins",
-	sources: func(target string) []string {
+	name: "compiler-rt",
+	cflags: func(target, headerPath string) []string {
+		return []string{"-Werror", "-Wall", "-std=c11", "-nostdlibinc"}
+	},
+	sourceDir: func() string {
+		llvmDir := filepath.Join(goenv.Get("TINYGOROOT"), "llvm-project/compiler-rt/lib/builtins")
+		if _, err := os.Stat(llvmDir); err == nil {
+			// Release build.
+			return llvmDir
+		}
+		// Development build.
+		return filepath.Join(goenv.Get("TINYGOROOT"), "lib/compiler-rt-builtins")
+	},
+	librarySources: func(target string) []string {
 		builtins := append([]string{}, genericBuiltins...) // copy genericBuiltins
 		if strings.HasPrefix(target, "arm") || strings.HasPrefix(target, "thumb") {
 			builtins = append(builtins, aeabiBuiltins...)

builder/cc.go

@@ -17,7 +17,6 @@ import (
 	"strings"
 	"unicode"
 
-	"github.com/tinygo-org/tinygo/compileopts"
 	"github.com/tinygo-org/tinygo/goenv"
 	"tinygo.org/x/go-llvm"
 )
@@ -57,25 +56,32 @@ import (
 //   depfile but without invalidating its name. For this reason, the depfile is
 //   written on each new compilation (even when it seems unnecessary). However, it
 //   could in rare cases lead to a stale file fetched from the cache.
-func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compileopts.Config) (string, error) {
+func compileAndCacheCFile(abspath, tmpdir string, cflags []string, thinlto bool, printCommands func(string, ...string)) (string, error) {
 	// Hash input file.
 	fileHash, err := hashFile(abspath)
 	if err != nil {
 		return "", err
 	}
 
+	// Acquire a lock (if supported).
+	unlock := lock(filepath.Join(goenv.Get("GOCACHE"), fileHash+".c.lock"))
+	defer unlock()
+
+	ext := ".o"
+	if thinlto {
+		ext = ".bc"
+	}
+
 	// Create cache key for the dependencies file.
 	buf, err := json.Marshal(struct {
 		Path        string
 		Hash        string
-		Compiler    string
 		Flags       []string
 		LLVMVersion string
 	}{
 		Path:        abspath,
 		Hash:        fileHash,
-		Compiler:    config.Target.Compiler,
-		Flags:       config.CFlags(),
+		Flags:       cflags,
 		LLVMVersion: llvm.Version,
 	})
 	if err != nil {
@@ -98,7 +104,7 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 		}
 
 		// Obtain hashes of all the files listed as a dependency.
-		outpath, err := makeCFileCachePath(dependencies, depfileNameHash)
+		outpath, err := makeCFileCachePath(dependencies, depfileNameHash, ext)
 		if err == nil {
 			if _, err := os.Stat(outpath); err == nil {
 				return outpath, nil
@@ -111,7 +117,7 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 		return "", err
 	}
 
-	objTmpFile, err := ioutil.TempFile(goenv.Get("GOCACHE"), "tmp-*.o")
+	objTmpFile, err := ioutil.TempFile(goenv.Get("GOCACHE"), "tmp-*"+ext)
 	if err != nil {
 		return "", err
 	}
@@ -123,11 +129,21 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 	depTmpFile.Close()
 	flags := append([]string{}, cflags...)                                   // copy cflags
 	flags = append(flags, "-MD", "-MV", "-MTdeps", "-MF", depTmpFile.Name()) // autogenerate dependencies
-	flags = append(flags, "-c", "-o", objTmpFile.Name(), abspath)
-	if config.Options.PrintCommands {
-		fmt.Printf("%s %s\n", config.Target.Compiler, strings.Join(flags, " "))
+	if thinlto {
+		flags = append(flags, "-flto=thin")
 	}
-	err = runCCompiler(config.Target.Compiler, flags...)
+	flags = append(flags, "-c", "-o", objTmpFile.Name(), abspath)
+	if strings.ToLower(filepath.Ext(abspath)) == ".s" {
+		// If this is an assembly file (.s or .S, lowercase or uppercase), then
+		// we'll need to add -Qunused-arguments because many parameters are
+		// relevant to C, not assembly. And with -Werror, having meaningless
+		// flags (for the assembler) is a compiler error.
+		flags = append(flags, "-Qunused-arguments")
+	}
+	if printCommands != nil {
+		printCommands("clang", flags...)
+	}
+	err = runCCompiler(flags...)
 	if err != nil {
 		return "", &commandError{"failed to build", abspath, err}
 	}
@@ -151,6 +167,10 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 
 	// Write dependencies file.
 	f, err := ioutil.TempFile(filepath.Dir(depfileCachePath), depfileName)
+	if err != nil {
+		return "", err
+	}
+
 	buf, err = json.MarshalIndent(dependencySlice, "", "\t")
 	if err != nil {
 		panic(err) // shouldn't happen
@@ -169,7 +189,7 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 	}
 
 	// Move temporary object file to final location.
-	outpath, err := makeCFileCachePath(dependencySlice, depfileNameHash)
+	outpath, err := makeCFileCachePath(dependencySlice, depfileNameHash, ext)
 	if err != nil {
 		return "", err
 	}
@@ -184,7 +204,7 @@ func compileAndCacheCFile(abspath, tmpdir string, cflags []string, config *compi
 // Create a cache path (a path in GOCACHE) to store the output of a compiler
 // job. This path is based on the dep file name (which is a hash of metadata
 // including compiler flags) and the hash of all input files in the paths slice.
-func makeCFileCachePath(paths []string, depfileNameHash string) (string, error) {
+func makeCFileCachePath(paths []string, depfileNameHash, ext string) (string, error) {
 	// Hash all input files.
 	fileHashes := make(map[string]string, len(paths))
 	for _, path := range paths {
@@ -209,7 +229,7 @@ func makeCFileCachePath(paths []string, depfileNameHash string) (string, error)
 	outFileNameBuf := sha512.Sum512_224(buf)
 	cacheKey := hex.EncodeToString(outFileNameBuf[:])
 
-	outpath := filepath.Join(goenv.Get("GOCACHE"), "obj-"+cacheKey+".o")
+	outpath := filepath.Join(goenv.Get("GOCACHE"), "obj-"+cacheKey+ext)
 	return outpath, nil
 }
 

builder/cc1as.cpp

@@ -38,6 +38,7 @@
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/TargetRegistry.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptTable.h"
@@ -51,7 +52,6 @@
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/SourceMgr.h"
-#include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/Timer.h"
 #include "llvm/Support/raw_ostream.h"
@@ -115,29 +115,25 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
   // Any DebugInfoKind implies GenDwarfForAssembly.
   Opts.GenDwarfForAssembly = Args.hasArg(OPT_debug_info_kind_EQ);
 
-  if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections,
-                                     OPT_compress_debug_sections_EQ)) {
-    if (A->getOption().getID() == OPT_compress_debug_sections) {
-      // TODO: be more clever about the compression type auto-detection
-      Opts.CompressDebugSections = llvm::DebugCompressionType::GNU;
-    } else {
-      Opts.CompressDebugSections =
-          llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
-              .Case("none", llvm::DebugCompressionType::None)
-              .Case("zlib", llvm::DebugCompressionType::Z)
-              .Case("zlib-gnu", llvm::DebugCompressionType::GNU)
-              .Default(llvm::DebugCompressionType::None);
-    }
+  if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections_EQ)) {
+    Opts.CompressDebugSections =
+        llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
+            .Case("none", llvm::DebugCompressionType::None)
+            .Case("zlib", llvm::DebugCompressionType::Z)
+            .Default(llvm::DebugCompressionType::None);
   }
 
   Opts.RelaxELFRelocations = Args.hasArg(OPT_mrelax_relocations);
+  if (auto *DwarfFormatArg = Args.getLastArg(OPT_gdwarf64, OPT_gdwarf32))
+    Opts.Dwarf64 = DwarfFormatArg->getOption().matches(OPT_gdwarf64);
   Opts.DwarfVersion = getLastArgIntValue(Args, OPT_dwarf_version_EQ, 2, Diags);
   Opts.DwarfDebugFlags =
       std::string(Args.getLastArgValue(OPT_dwarf_debug_flags));
   Opts.DwarfDebugProducer =
       std::string(Args.getLastArgValue(OPT_dwarf_debug_producer));
-  Opts.DebugCompilationDir =
-      std::string(Args.getLastArgValue(OPT_fdebug_compilation_dir));
+  if (const Arg *A = Args.getLastArg(options::OPT_ffile_compilation_dir_EQ,
+                                     options::OPT_fdebug_compilation_dir_EQ))
+    Opts.DebugCompilationDir = A->getValue();
   Opts.MainFileName = std::string(Args.getLastArgValue(OPT_main_file_name));
 
   for (const auto &Arg : Args.getAllArgValues(OPT_fdebug_prefix_map_EQ)) {
@@ -219,7 +215,7 @@ getOutputStream(StringRef Path, DiagnosticsEngine &Diags, bool Binary) {
 
   std::error_code EC;
   auto Out = std::make_unique<raw_fd_ostream>(
-      Path, EC, (Binary ? sys::fs::OF_None : sys::fs::OF_Text));
+      Path, EC, (Binary ? sys::fs::OF_None : sys::fs::OF_TextWithCRLF));
   if (EC) {
     Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
     return nullptr;
@@ -228,7 +224,8 @@ getOutputStream(StringRef Path, DiagnosticsEngine &Diags, bool Binary) {
   return Out;
 }
 
-bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
+static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
+                                 DiagnosticsEngine &Diags) {
   // Get the target specific parser.
   std::string Error;
   const Target *TheTarget = TargetRegistry::lookupTarget(Opts.Triple, Error);
@@ -236,7 +233,7 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
     return Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
 
   ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
-      MemoryBuffer::getFileOrSTDIN(Opts.InputFile);
+      MemoryBuffer::getFileOrSTDIN(Opts.InputFile, /*IsText=*/true);
 
   if (std::error_code EC = Buffer.getError()) {
     Error = EC.message();
@@ -277,11 +274,15 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
   if (!Opts.SplitDwarfOutput.empty())
     DwoOS = getOutputStream(Opts.SplitDwarfOutput, Diags, IsBinary);
 
-  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
-  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
-  std::unique_ptr<MCObjectFileInfo> MOFI(new MCObjectFileInfo());
+  // Build up the feature string from the target feature list.
+  std::string FS = llvm::join(Opts.Features, ",");
 
-  MCContext Ctx(MAI.get(), MRI.get(), MOFI.get(), &SrcMgr, &MCOptions);
+  std::unique_ptr<MCSubtargetInfo> STI(
+      TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
+  assert(STI && "Unable to create subtarget info!");
+
+  MCContext Ctx(Triple(Opts.Triple), MAI.get(), MRI.get(), STI.get(), &SrcMgr,
+                &MCOptions);
 
   bool PIC = false;
   if (Opts.RelocationModel == "static") {
@@ -294,7 +295,12 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
     PIC = false;
   }
 
-  MOFI->InitMCObjectFileInfo(Triple(Opts.Triple), PIC, Ctx);
+  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
+  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
+  std::unique_ptr<MCObjectFileInfo> MOFI(
+      TheTarget->createMCObjectFileInfo(Ctx, PIC));
+  Ctx.setObjectFileInfo(MOFI.get());
+
   if (Opts.SaveTemporaryLabels)
     Ctx.setAllowTemporaryLabels(false);
   if (Opts.GenDwarfForAssembly)
@@ -316,19 +322,16 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
       Ctx.addDebugPrefixMapEntry(KV.first, KV.second);
   if (!Opts.MainFileName.empty())
     Ctx.setMainFileName(StringRef(Opts.MainFileName));
+  Ctx.setDwarfFormat(Opts.Dwarf64 ? dwarf::DWARF64 : dwarf::DWARF32);
   Ctx.setDwarfVersion(Opts.DwarfVersion);
   if (Opts.GenDwarfForAssembly)
     Ctx.setGenDwarfRootFile(Opts.InputFile,
                             SrcMgr.getMemoryBuffer(BufferIndex)->getBuffer());
 
-  // Build up the feature string from the target feature list.
-  std::string FS = llvm::join(Opts.Features, ",");
-
   std::unique_ptr<MCStreamer> Str;
 
   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
-  std::unique_ptr<MCSubtargetInfo> STI(
-      TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
+  assert(MCII && "Unable to create instruction info!");
 
   raw_pwrite_stream *Out = FDOS.get();
   std::unique_ptr<buffer_ostream> BOS;
@@ -367,6 +370,8 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
         TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx));
     std::unique_ptr<MCAsmBackend> MAB(
         TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));
+    assert(MAB && "Unable to create asm backend!");
+
     std::unique_ptr<MCObjectWriter> OW =
         DwoOS ? MAB->createDwoObjectWriter(*Out, *DwoOS)
               : MAB->createObjectWriter(*Out);
@@ -376,13 +381,12 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
         T, Ctx, std::move(MAB), std::move(OW), std::move(CE), *STI,
         Opts.RelaxAll, Opts.IncrementalLinkerCompatible,
         /*DWARFMustBeAtTheEnd*/ true));
-    Str.get()->InitSections(Opts.NoExecStack);
+    Str.get()->initSections(Opts.NoExecStack, *STI);
   }
 
   // When -fembed-bitcode is passed to clang_as, a 1-byte marker
   // is emitted in __LLVM,__asm section if the object file is MachO format.
-  if (Opts.EmbedBitcode && Ctx.getObjectFileInfo()->getObjectFileType() ==
-                               MCObjectFileInfo::IsMachO) {
+  if (Opts.EmbedBitcode && Ctx.getObjectFileType() == MCContext::IsMachO) {
     MCSection *AsmLabel = Ctx.getMachOSection(
         "__LLVM", "__asm", MachO::S_REGULAR, 4, SectionKind::getReadOnly());
     Str.get()->SwitchSection(AsmLabel);
@@ -419,12 +423,12 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
     Failed = Parser->Run(Opts.NoInitialTextSection);
   }
 
-  // Close Streamer first.
-  // It might have a reference to the output stream.
-  Str.reset();
-  // Close the output stream early.
-  BOS.reset();
-  FDOS.reset();
+  return Failed;
+}
+
+bool ExecuteAssembler(AssemblerInvocation &Opts,
+                             DiagnosticsEngine &Diags) {
+  bool Failed = ExecuteAssemblerImpl(Opts, Diags);
 
   // Delete output file if there were errors.
   if (Failed) {
@@ -437,7 +441,7 @@ bool ExecuteAssembler(AssemblerInvocation &Opts, DiagnosticsEngine &Diags) {
   return Failed;
 }
 
-static void LLVMErrorHandler(void *UserData, const std::string &Message,
+static void LLVMErrorHandler(void *UserData, const char *Message,
                              bool GenCrashDiag) {
   DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
 
@@ -472,7 +476,7 @@ int cc1as_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
     return 1;
 
   if (Asm.ShowHelp) {
-    getDriverOptTable().PrintHelp(
+    getDriverOptTable().printHelp(
         llvm::outs(), "clang -cc1as [options] file...",
         "Clang Integrated Assembler",
         /*Include=*/driver::options::CC1AsOption, /*Exclude=*/0,

builder/cc1as.h

@@ -39,6 +39,7 @@ struct AssemblerInvocation {
   unsigned SaveTemporaryLabels : 1;
   unsigned GenDwarfForAssembly : 1;
   unsigned RelaxELFRelocations : 1;
+  unsigned Dwarf64 : 1;
   unsigned DwarfVersion;
   std::string DwarfDebugFlags;
   std::string DwarfDebugProducer;
@@ -108,6 +109,7 @@ public:
     FatalWarnings = 0;
     NoWarn = 0;
     IncrementalLinkerCompatible = 0;
+    Dwarf64 = 0;
     DwarfVersion = 0;
     EmbedBitcode = 0;
   }

builder/commands.go

@@ -2,6 +2,7 @@ package builder
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"os/exec"
 	"runtime"
@@ -21,13 +22,24 @@ func init() {
 	commands["clang"] = []string{"clang-" + llvmMajor}
 	commands["ld.lld"] = []string{"ld.lld-" + llvmMajor, "ld.lld"}
 	commands["wasm-ld"] = []string{"wasm-ld-" + llvmMajor, "wasm-ld"}
+	commands["lldb"] = []string{"lldb-" + llvmMajor, "lldb"}
 	// Add the path to a Homebrew-installed LLVM for ease of use (no need to
 	// manually set $PATH).
 	if runtime.GOOS == "darwin" {
-		prefix := "/usr/local/opt/llvm@" + llvmMajor + "/bin/"
+		var prefix string
+		switch runtime.GOARCH {
+		case "amd64":
+			prefix = "/usr/local/opt/llvm@" + llvmMajor + "/bin/"
+		case "arm64":
+			prefix = "/opt/homebrew/opt/llvm@" + llvmMajor + "/bin/"
+		default:
+			// unknown GOARCH
+			panic(fmt.Sprintf("unknown GOARCH: %s on darwin", runtime.GOARCH))
+		}
 		commands["clang"] = append(commands["clang"], prefix+"clang-"+llvmMajor)
 		commands["ld.lld"] = append(commands["ld.lld"], prefix+"ld.lld")
 		commands["wasm-ld"] = append(commands["wasm-ld"], prefix+"wasm-ld")
+		commands["lldb"] = append(commands["lldb"], prefix+"lldb")
 	}
 	// Add the path for when LLVM was installed with the installer from
 	// llvm.org, which by default doesn't add LLVM to the $PATH environment
@@ -36,6 +48,7 @@ func init() {
 		commands["clang"] = append(commands["clang"], "clang", "C:\\Program Files\\LLVM\\bin\\clang.exe")
 		commands["ld.lld"] = append(commands["ld.lld"], "lld", "C:\\Program Files\\LLVM\\bin\\lld.exe")
 		commands["wasm-ld"] = append(commands["wasm-ld"], "C:\\Program Files\\LLVM\\bin\\wasm-ld.exe")
+		commands["lldb"] = append(commands["lldb"], "C:\\Program Files\\LLVM\\bin\\lldb.exe")
 	}
 	// Add the path to LLVM installed from ports.
 	if runtime.GOOS == "freebsd" {
@@ -43,23 +56,34 @@ func init() {
 		commands["clang"] = append(commands["clang"], prefix+"clang-"+llvmMajor)
 		commands["ld.lld"] = append(commands["ld.lld"], prefix+"ld.lld")
 		commands["wasm-ld"] = append(commands["wasm-ld"], prefix+"wasm-ld")
+		commands["lldb"] = append(commands["lldb"], prefix+"lldb")
 	}
 }
 
-func execCommand(cmdNames []string, args ...string) error {
-	for _, cmdName := range cmdNames {
-		cmd := exec.Command(cmdName, args...)
-		cmd.Stdout = os.Stdout
-		cmd.Stderr = os.Stderr
-		err := cmd.Run()
+// LookupCommand looks up the executable name for a given LLVM tool such as
+// clang or wasm-ld. It returns the (relative) command that can be used to
+// invoke the tool or an error if it could not be found.
+func LookupCommand(name string) (string, error) {
+	for _, cmdName := range commands[name] {
+		_, err := exec.LookPath(cmdName)
 		if err != nil {
-			if err, ok := err.(*exec.Error); ok && (err.Err == exec.ErrNotFound || err.Err.Error() == "file does not exist") {
-				// this command was not found, try the next
+			if errors.Unwrap(err) == exec.ErrNotFound {
 				continue
 			}
-			return err
+			return cmdName, err
 		}
-		return nil
+		return cmdName, nil
 	}
-	return errors.New("none of these commands were found in your $PATH: " + strings.Join(cmdNames, " "))
+	return "", errors.New("none of these commands were found in your $PATH: " + strings.Join(commands[name], " "))
+}
+
+func execCommand(name string, args ...string) error {
+	name, err := LookupCommand(name)
+	if err != nil {
+		return err
+	}
+	cmd := exec.Command(name, args...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
 }

builder/config.go

@@ -13,22 +13,32 @@ import (
 // uses the currently active GOPATH (from the goenv package) to determine the Go
 // version to use.
 func NewConfig(options *compileopts.Options) (*compileopts.Config, error) {
-	spec, err := compileopts.LoadTarget(options.Target)
+	spec, err := compileopts.LoadTarget(options)
 	if err != nil {
 		return nil, err
 	}
+
+	if options.OpenOCDCommands != nil {
+		// Override the OpenOCDCommands from the target spec if specified on
+		// the command-line
+		spec.OpenOCDCommands = options.OpenOCDCommands
+	}
+
 	goroot := goenv.Get("GOROOT")
 	if goroot == "" {
 		return nil, errors.New("cannot locate $GOROOT, please set it manually")
 	}
+
 	major, minor, err := goenv.GetGorootVersion(goroot)
 	if err != nil {
 		return nil, fmt.Errorf("could not read version from GOROOT (%v): %v", goroot, err)
 	}
-	if major != 1 || minor < 13 || minor > 16 {
-		return nil, fmt.Errorf("requires go version 1.13 through 1.16, got go%d.%d", major, minor)
+	if major != 1 || minor < 16 || minor > 18 {
+		return nil, fmt.Errorf("requires go version 1.16 through 1.18, got go%d.%d", major, minor)
 	}
+
 	clangHeaderPath := getClangHeaderPath(goenv.Get("TINYGOROOT"))
+
 	return &compileopts.Config{
 		Options:        options,
 		Target:         spec,

builder/darwin-libsystem.go

@@ -0,0 +1,58 @@
+package builder
+
+import (
+	"path/filepath"
+	"strings"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/goenv"
+)
+
+// Create a job that builds a Darwin libSystem.dylib stub library. This library
+// contains all the symbols needed so that we can link against it, but it
+// doesn't contain any real symbol implementations.
+func makeDarwinLibSystemJob(config *compileopts.Config, tmpdir string) *compileJob {
+	return &compileJob{
+		description: "compile Darwin libSystem.dylib",
+		run: func(job *compileJob) (err error) {
+			arch := strings.Split(config.Triple(), "-")[0]
+			job.result = filepath.Join(tmpdir, "libSystem.dylib")
+			objpath := filepath.Join(tmpdir, "libSystem.o")
+			inpath := filepath.Join(goenv.Get("TINYGOROOT"), "lib/macos-minimal-sdk/src", arch, "libSystem.s")
+
+			// Compile assembly file to object file.
+			flags := []string{
+				"-nostdlib",
+				"--target=" + config.Triple(),
+				"-c",
+				"-o", objpath,
+				inpath,
+			}
+			if config.Options.PrintCommands != nil {
+				config.Options.PrintCommands("clang", flags...)
+			}
+			err = runCCompiler(flags...)
+			if err != nil {
+				return err
+			}
+
+			// Link object file to dynamic library.
+			platformVersion := strings.TrimPrefix(strings.Split(config.Triple(), "-")[2], "macosx")
+			flags = []string{
+				"-flavor", "darwin",
+				"-demangle",
+				"-dynamic",
+				"-dylib",
+				"-arch", arch,
+				"-platform_version", "macos", platformVersion, platformVersion,
+				"-install_name", "/usr/lib/libSystem.B.dylib",
+				"-o", job.result,
+				objpath,
+			}
+			if config.Options.PrintCommands != nil {
+				config.Options.PrintCommands("ld.lld", flags...)
+			}
+			return link("ld.lld", flags...)
+		},
+	}
+}

builder/elfpatch.go

@@ -0,0 +1,57 @@
+package builder
+
+import (
+	"debug/elf"
+	"fmt"
+	"os"
+)
+
+func getElfSectionData(executable string, sectionName string) ([]byte, elf.FileHeader, error) {
+	elfFile, err := elf.Open(executable)
+	if err != nil {
+		return nil, elf.FileHeader{}, err
+	}
+	defer elfFile.Close()
+
+	section := elfFile.Section(sectionName)
+	if section == nil {
+		return nil, elf.FileHeader{}, fmt.Errorf("could not find %s section", sectionName)
+	}
+
+	data, err := section.Data()
+
+	return data, elfFile.FileHeader, err
+}
+
+func replaceElfSection(executable string, sectionName string, data []byte) error {
+	fp, err := os.OpenFile(executable, os.O_RDWR, 0)
+	if err != nil {
+		return err
+	}
+	defer fp.Close()
+
+	elfFile, err := elf.Open(executable)
+	if err != nil {
+		return err
+	}
+	defer elfFile.Close()
+
+	section := elfFile.Section(sectionName)
+	if section == nil {
+		return fmt.Errorf("could not find %s section", sectionName)
+	}
+
+	// Implicitly check for compressed sections
+	if section.Size != section.FileSize {
+		return fmt.Errorf("expected section %s to have identical size and file size, got %d and %d", sectionName, section.Size, section.FileSize)
+	}
+
+	// Only permit complete replacement of section
+	if section.Size != uint64(len(data)) {
+		return fmt.Errorf("expected section %s to have size %d, was actually %d", sectionName, len(data), section.Size)
+	}
+
+	// Write the replacement section data
+	_, err = fp.WriteAt(data, int64(section.Offset))
+	return err
+}

builder/env.go

@@ -84,6 +84,20 @@ func getClangHeaderPath(TINYGOROOT string) string {
 		}
 	}
 
+	// On Arch Linux, the clang executable is stored in /usr/bin rather than being symlinked from there.
+	// Search directly in /usr/lib for clang.
+	if matches, err := filepath.Glob("/usr/lib/clang/" + llvmMajor + ".*.*"); err == nil {
+		// Check for the highest version first.
+		sort.Strings(matches)
+		for i := len(matches) - 1; i >= 0; i-- {
+			path := filepath.Join(matches[i], "include")
+			_, err := os.Stat(filepath.Join(path, "stdint.h"))
+			if err == nil {
+				return path
+			}
+		}
+	}
+
 	// Could not find it.
 	return ""
 }

builder/esp.go

@@ -15,6 +15,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"sort"
+	"strings"
 )
 
 type espImageSegment struct {
@@ -78,11 +79,37 @@ func makeESPFirmareImage(infile, outfile, format string) error {
 	// An added benefit is that we don't need to check for errors all the time.
 	outf := &bytes.Buffer{}
 
+	// Separate esp32 and esp32-img. The -img suffix indicates we should make an
+	// image, not just a binary to be flashed at 0x1000 for example.
+	chip := format
+	makeImage := false
+	if strings.HasSuffix(format, "-img") {
+		makeImage = true
+		chip = format[:len(format)-len("-img")]
+	}
+
+	if makeImage {
+		// The bootloader starts at 0x1000, or 4096.
+		// TinyGo doesn't use a separate bootloader and runs the entire
+		// application in the bootloader location.
+		outf.Write(make([]byte, 4096))
+	}
+
+	// Chip IDs. Source:
+	// https://github.com/espressif/esp-idf/blob/v4.3/components/bootloader_support/include/esp_app_format.h#L22
+	chip_id := map[string]uint16{
+		"esp32":   0x0000,
+		"esp32c3": 0x0005,
+	}[chip]
+
 	// Image header.
-	switch format {
-	case "esp32":
+	switch chip {
+	case "esp32", "esp32c3":
 		// Header format:
-		// https://github.com/espressif/esp-idf/blob/8fbb63c2/components/bootloader_support/include/esp_image_format.h#L58
+		// https://github.com/espressif/esp-idf/blob/v4.3/components/bootloader_support/include/esp_app_format.h#L71
+		// Note: not adding a SHA256 hash as the binary is modified by
+		// esptool.py while flashing and therefore the hash won't be valid
+		// anymore.
 		binary.Write(outf, binary.LittleEndian, struct {
 			magic          uint8
 			segment_count  uint8
@@ -91,15 +118,18 @@ func makeESPFirmareImage(infile, outfile, format string) error {
 			entry_addr     uint32
 			wp_pin         uint8
 			spi_pin_drv    [3]uint8
-			reserved       [11]uint8
+			chip_id        uint16
+			min_chip_rev   uint8
+			reserved       [8]uint8
 			hash_appended  bool
 		}{
 			magic:          0xE9,
 			segment_count:  byte(len(segments)),
-			spi_mode:       0, // irrelevant, replaced by esptool when flashing
-			spi_speed_size: 0, // spi_speed, spi_size: replaced by esptool when flashing
+			spi_mode:       2,    // ESP_IMAGE_SPI_MODE_DIO
+			spi_speed_size: 0x1f, // ESP_IMAGE_SPI_SPEED_80M, ESP_IMAGE_FLASH_SIZE_2MB
 			entry_addr:     uint32(inf.Entry),
 			wp_pin:         0xEE, // disable WP pin
+			chip_id:        chip_id,
 			hash_appended:  true, // add a SHA256 hash
 		})
 	case "esp8266":
@@ -142,12 +172,22 @@ func makeESPFirmareImage(infile, outfile, format string) error {
 	outf.Write(make([]byte, 15-outf.Len()%16))
 	outf.WriteByte(checksum)
 
-	if format == "esp32" {
+	if chip != "esp8266" {
 		// SHA256 hash (to protect against image corruption, not for security).
 		hash := sha256.Sum256(outf.Bytes())
 		outf.Write(hash[:])
 	}
 
+	// QEMU (or more precisely, qemu-system-xtensa from Espressif) expects the
+	// image to be a certain size.
+	if makeImage {
+		// Use a default image size of 4MB.
+		grow := 4096*1024 - outf.Len()
+		if grow > 0 {
+			outf.Write(make([]byte, grow))
+		}
+	}
+
 	// Write the image to the output file.
 	return ioutil.WriteFile(outfile, outf.Bytes(), 0666)
 }

builder/jobs.go

@@ -4,8 +4,12 @@ package builder
 // parallel while taking care of dependencies.
 
 import (
+	"container/heap"
+	"errors"
 	"fmt"
 	"runtime"
+	"sort"
+	"strings"
 	"time"
 )
 
@@ -29,7 +33,6 @@ type compileJob struct {
 	dependencies []*compileJob
 	result       string // result (path)
 	run          func(*compileJob) (err error)
-	state        jobState
 	err          error         // error if finished
 	duration     time.Duration // how long it took to run this job (only set after finishing)
 }
@@ -44,91 +47,123 @@ func dummyCompileJob(result string) *compileJob {
 	}
 }
 
-// readyToRun returns whether this job is ready to run: it is itself not yet
-// started and all dependencies are finished.
-func (job *compileJob) readyToRun() bool {
-	if job.state != jobStateQueued {
-		// Already running or finished, so shouldn't be run again.
-		return false
+// runJobs runs the indicated job and all its dependencies. For every job, all
+// the dependencies are run first. It returns the error of the first job that
+// fails.
+// It runs all jobs in the order of the dependencies slice, depth-first.
+// Therefore, if some jobs are preferred to run before others, they should be
+// ordered as such in the job dependencies.
+func runJobs(job *compileJob, sema chan struct{}) error {
+	if sema == nil {
+		// Have a default, if the semaphore isn't set. This is useful for
+		// tests.
+		sema = make(chan struct{}, runtime.NumCPU())
+	}
+	if cap(sema) == 0 {
+		return errors.New("cannot 0 jobs at a time")
 	}
 
-	// Check dependencies.
-	for _, dep := range job.dependencies {
-		if dep.state != jobStateFinished {
-			// A dependency is not finished, so this job has to wait until it
-			// is.
-			return false
+	// Create a slice of jobs to run, where all dependencies are run in order.
+	jobs := []*compileJob{}
+	addedJobs := map[*compileJob]struct{}{}
+	var addJobs func(*compileJob)
+	addJobs = func(job *compileJob) {
+		if _, ok := addedJobs[job]; ok {
+			return
+		}
+		for _, dep := range job.dependencies {
+			addJobs(dep)
+		}
+		jobs = append(jobs, job)
+		addedJobs[job] = struct{}{}
+	}
+	addJobs(job)
+
+	waiting := make(map[*compileJob]map[*compileJob]struct{}, len(jobs))
+	dependents := make(map[*compileJob][]*compileJob, len(jobs))
+	jidx := make(map[*compileJob]int)
+	var ready intHeap
+	for i, job := range jobs {
+		jidx[job] = i
+		if len(job.dependencies) == 0 {
+			// This job is ready to run.
+			ready.Push(i)
+			continue
+		}
+
+		// Construct a map for dependencies which the job is currently waiting on.
+		waitDeps := make(map[*compileJob]struct{})
+		waiting[job] = waitDeps
+
+		// Add the job to the dependents list of each dependency.
+		for _, dep := range job.dependencies {
+			dependents[dep] = append(dependents[dep], job)
+			waitDeps[dep] = struct{}{}
 		}
 	}
 
-	// All conditions are satisfied.
-	return true
-}
-
-// runJobs runs all the jobs indicated in the jobs slice and returns the error
-// of the first job that fails to run.
-// It runs all jobs in the order of the slice, as long as all dependencies have
-// already run. Therefore, if some jobs are preferred to run before others, they
-// should be ordered as such in this slice.
-func runJobs(jobs []*compileJob) error {
-	// Create channels to communicate with the workers.
+	// Create a channel to accept notifications of completion.
 	doneChan := make(chan *compileJob)
-	workerChan := make(chan *compileJob)
-	defer close(workerChan)
-
-	// Start a number of workers.
-	for i := 0; i < runtime.NumCPU(); i++ {
-		if jobRunnerDebug {
-			fmt.Println("## starting worker", i)
-		}
-		go jobWorker(workerChan, doneChan)
-	}
 
 	// Send each job in the jobs slice to a worker, taking care of job
 	// dependencies.
 	numRunningJobs := 0
 	var totalTime time.Duration
 	start := time.Now()
-	for {
-		// If there are free workers, try starting a new job (if one is
-		// available). If it succeeds, try again to fill the entire worker pool.
-		if numRunningJobs < runtime.NumCPU() {
-			jobToRun := nextJob(jobs)
-			if jobToRun != nil {
-				// Start job.
+	for len(ready.IntSlice) > 0 || numRunningJobs != 0 {
+		var completed *compileJob
+		if len(ready.IntSlice) > 0 {
+			select {
+			case sema <- struct{}{}:
+				// Start a job.
+				job := jobs[heap.Pop(&ready).(int)]
 				if jobRunnerDebug {
-					fmt.Println("## start:   ", jobToRun.description)
+					fmt.Println("## start:   ", job.description)
 				}
-				jobToRun.state = jobStateRunning
-				workerChan <- jobToRun
+				go runJob(job, doneChan)
 				numRunningJobs++
 				continue
+
+			case completed = <-doneChan:
+				// A job completed.
 			}
+		} else {
+			// Wait for a job to complete.
+			completed = <-doneChan
 		}
-
-		// When there are no jobs running, all jobs in the jobs slice must have
-		// been finished. Therefore, the work is done.
-		if numRunningJobs == 0 {
-			break
-		}
-
-		// Wait until a job is finished.
-		job := <-doneChan
-		job.state = jobStateFinished
 		numRunningJobs--
-		totalTime += job.duration
+		<-sema
 		if jobRunnerDebug {
 			fmt.Println("## finished:", job.description, "(time "+job.duration.String()+")")
 		}
-		if job.err != nil {
-			// Wait for running jobs to finish.
+		if completed.err != nil {
+			// Wait for any current jobs to finish.
 			for numRunningJobs != 0 {
 				<-doneChan
 				numRunningJobs--
 			}
-			// Return error of first failing job.
-			return job.err
+
+			// The build failed.
+			return completed.err
 		}
+
+		// Update total run time.
+		totalTime += completed.duration
+
+		// Update dependent jobs.
+		for _, j := range dependents[completed] {
+			wait := waiting[j]
+			delete(wait, completed)
+			if len(wait) == 0 {
+				// This job is now ready to run.
+				ready.Push(jidx[j])
+				delete(waiting, j)
+			}
+		}
+	}
+	if len(waiting) != 0 {
+		// There is a dependency cycle preventing some jobs from running.
+		return errDependencyCycle{waiting}
 	}
 
 	// Some statistics, if debugging.
@@ -145,29 +180,50 @@ func runJobs(jobs []*compileJob) error {
 	return nil
 }
 
-// nextJob returns the first ready-to-run job.
-// This is an implementation detail of runJobs.
-func nextJob(jobs []*compileJob) *compileJob {
-	for _, job := range jobs {
-		if job.readyToRun() {
-			return job
-		}
-	}
-	return nil
+type errDependencyCycle struct {
+	waiting map[*compileJob]map[*compileJob]struct{}
 }
 
-// jobWorker is the goroutine that runs received jobs.
-// This is an implementation detail of runJobs.
-func jobWorker(workerChan, doneChan chan *compileJob) {
-	for job := range workerChan {
-		start := time.Now()
-		if job.run != nil {
-			err := job.run(job)
-			if err != nil {
-				job.err = err
-			}
+func (err errDependencyCycle) Error() string {
+	waits := make([]string, 0, len(err.waiting))
+	for j, wait := range err.waiting {
+		deps := make([]string, 0, len(wait))
+		for dep := range wait {
+			deps = append(deps, dep.description)
 		}
-		job.duration = time.Since(start)
-		doneChan <- job
+		sort.Strings(deps)
+
+		waits = append(waits, fmt.Sprintf("\t%s is waiting for [%s]",
+			j.description, strings.Join(deps, ", "),
+		))
 	}
+	sort.Strings(waits)
+	return "deadlock:\n" + strings.Join(waits, "\n")
+}
+
+type intHeap struct {
+	sort.IntSlice
+}
+
+func (h *intHeap) Push(x interface{}) {
+	h.IntSlice = append(h.IntSlice, x.(int))
+}
+
+func (h *intHeap) Pop() interface{} {
+	x := h.IntSlice[len(h.IntSlice)-1]
+	h.IntSlice = h.IntSlice[:len(h.IntSlice)-1]
+	return x
+}
+
+// runJob runs a compile job and notifies doneChan of completion.
+func runJob(job *compileJob, doneChan chan *compileJob) {
+	start := time.Now()
+	if job.run != nil {
+		err := job.run(job)
+		if err != nil {
+			job.err = err
+		}
+	}
+	job.duration = time.Since(start)
+	doneChan <- job
 }

builder/library.go

@@ -1,10 +1,14 @@
 package builder
 
 import (
+	"io/ioutil"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strings"
+	"sync"
 
+	"github.com/tinygo-org/tinygo/compileopts"
 	"github.com/tinygo-org/tinygo/goenv"
 )
 
@@ -14,89 +18,151 @@ type Library struct {
 	// The library name, such as compiler-rt or picolibc.
 	name string
 
-	cflags func() []string
+	// makeHeaders creates a header include dir for the library
+	makeHeaders func(target, includeDir string) error
 
-	// The source directory, relative to TINYGOROOT.
-	sourceDir string
+	// cflags returns the C flags specific to this library
+	cflags func(target, headerPath string) []string
+
+	// The source directory.
+	sourceDir func() string
 
 	// The source files, relative to sourceDir.
-	sources func(target string) []string
-}
+	librarySources func(target string) []string
 
-// fullPath returns the full path to the source directory.
-func (l *Library) fullPath() string {
-	return filepath.Join(goenv.Get("TINYGOROOT"), l.sourceDir)
-}
-
-// sourcePaths returns a slice with the full paths to the source files.
-func (l *Library) sourcePaths(target string) []string {
-	sources := l.sources(target)
-	paths := make([]string, len(sources))
-	for i, name := range sources {
-		paths[i] = filepath.Join(l.fullPath(), name)
-	}
-	return paths
+	// The source code for the crt1.o file, relative to sourceDir.
+	crt1Source string
 }
 
 // Load the library archive, possibly generating and caching it if needed.
-// The resulting file is stored in the provided tmpdir, which is expected to be
-// removed after the Load call.
-func (l *Library) Load(target, tmpdir string) (path string, err error) {
-	job, err := l.load(target, "", tmpdir)
+// The resulting directory may be stored in the provided tmpdir, which is
+// expected to be removed after the Load call.
+func (l *Library) Load(config *compileopts.Config, tmpdir string) (dir string, err error) {
+	job, unlock, err := l.load(config, tmpdir)
 	if err != nil {
 		return "", err
 	}
-	jobs := append([]*compileJob{job}, job.dependencies...)
-	err = runJobs(jobs)
-	return job.result, err
+	defer unlock()
+	err = runJobs(job, config.Options.Semaphore)
+	return filepath.Dir(job.result), err
 }
 
 // load returns a compile job to build this library file for the given target
 // and CPU. It may return a dummy compileJob if the library build is already
-// cached. The path is stored as job.result but is only valid if the job and
-// job.dependencies have been run.
+// cached. The path is stored as job.result but is only valid after the job has
+// been run.
 // The provided tmpdir will be used to store intermediary files and possibly the
 // output archive file, it is expected to be removed after use.
-func (l *Library) load(target, cpu, tmpdir string) (job *compileJob, err error) {
-	// Try to load a precompiled library.
-	precompiledPath := filepath.Join(goenv.Get("TINYGOROOT"), "pkg", target, l.name+".a")
-	if _, err := os.Stat(precompiledPath); err == nil {
+// As a side effect, this call creates the library header files if they didn't
+// exist yet.
+func (l *Library) load(config *compileopts.Config, tmpdir string) (job *compileJob, abortLock func(), err error) {
+	outdir, precompiled := config.LibcPath(l.name)
+	archiveFilePath := filepath.Join(outdir, "lib.a")
+	if precompiled {
 		// Found a precompiled library for this OS/architecture. Return the path
 		// directly.
-		return dummyCompileJob(precompiledPath), nil
+		return dummyCompileJob(archiveFilePath), func() {}, nil
 	}
 
-	var outfile string
-	if cpu != "" {
-		outfile = l.name + "-" + target + "-" + cpu + ".a"
-	} else {
-		outfile = l.name + "-" + target + ".a"
-	}
+	// Create a lock on the output (if supported).
+	// This is a bit messy, but avoids a deadlock because it is ordered consistently with other library loads within a build.
+	outname := filepath.Base(outdir)
+	unlock := lock(filepath.Join(goenv.Get("GOCACHE"), outname+".lock"))
+	var ok bool
+	defer func() {
+		if !ok {
+			unlock()
+		}
+	}()
 
 	// Try to fetch this library from the cache.
-	if path, err := cacheLoad(outfile, l.sourcePaths(target)); path != "" || err != nil {
-		// Cache hit.
-		return dummyCompileJob(path), nil
+	if _, err := os.Stat(archiveFilePath); err == nil {
+		return dummyCompileJob(archiveFilePath), func() {}, nil
 	}
 	// Cache miss, build it now.
 
+	// Create the destination directory where the components of this library
+	// (lib.a file, include directory) are placed.
+	err = os.MkdirAll(filepath.Join(goenv.Get("GOCACHE"), outname), 0o777)
+	if err != nil {
+		// Could not create directory (and not because it already exists).
+		return nil, nil, err
+	}
+
+	// Make headers if needed.
+	headerPath := filepath.Join(outdir, "include")
+	target := config.Triple()
+	if l.makeHeaders != nil {
+		if _, err = os.Stat(headerPath); err != nil {
+			temporaryHeaderPath, err := ioutil.TempDir(outdir, "include.tmp*")
+			if err != nil {
+				return nil, nil, err
+			}
+			defer os.RemoveAll(temporaryHeaderPath)
+			err = l.makeHeaders(target, temporaryHeaderPath)
+			if err != nil {
+				return nil, nil, err
+			}
+			err = os.Chmod(temporaryHeaderPath, 0o755) // TempDir uses 0o700 by default
+			if err != nil {
+				return nil, nil, err
+			}
+			err = os.Rename(temporaryHeaderPath, headerPath)
+			if err != nil {
+				switch {
+				case os.IsExist(err):
+					// Another invocation of TinyGo also seems to have already created the headers.
+
+				case runtime.GOOS == "windows" && os.IsPermission(err):
+					// On Windows, a rename with a destination directory that already
+					// exists does not result in an IsExist error, but rather in an
+					// access denied error. To be sure, check for this case by checking
+					// whether the target directory exists.
+					if _, err := os.Stat(headerPath); err == nil {
+						break
+					}
+					fallthrough
+
+				default:
+					return nil, nil, err
+				}
+			}
+		}
+	}
+
 	remapDir := filepath.Join(os.TempDir(), "tinygo-"+l.name)
 	dir := filepath.Join(tmpdir, "build-lib-"+l.name)
 	err = os.Mkdir(dir, 0777)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	// Precalculate the flags to the compiler invocation.
 	// Note: -fdebug-prefix-map is necessary to make the output archive
 	// reproducible. Otherwise the temporary directory is stored in the archive
 	// itself, which varies each run.
-	args := append(l.cflags(), "-c", "-Oz", "-g", "-ffunction-sections", "-fdata-sections", "-Wno-macro-redefined", "--target="+target, "-fdebug-prefix-map="+dir+"="+remapDir)
+	args := append(l.cflags(target, headerPath), "-c", "-Oz", "-g", "-ffunction-sections", "-fdata-sections", "-Wno-macro-redefined", "--target="+target, "-fdebug-prefix-map="+dir+"="+remapDir)
+	cpu := config.CPU()
 	if cpu != "" {
-		args = append(args, "-mcpu="+cpu)
+		// X86 has deprecated the -mcpu flag, so we need to use -march instead.
+		// However, ARM has not done this.
+		if strings.HasPrefix(target, "i386") || strings.HasPrefix(target, "x86_64") {
+			args = append(args, "-march="+cpu)
+		} else if strings.HasPrefix(target, "avr") {
+			args = append(args, "-mmcu="+cpu)
+		} else {
+			args = append(args, "-mcpu="+cpu)
+		}
 	}
 	if strings.HasPrefix(target, "arm") || strings.HasPrefix(target, "thumb") {
-		args = append(args, "-fshort-enums", "-fomit-frame-pointer", "-mfloat-abi=soft")
+		args = append(args, "-fshort-enums", "-fomit-frame-pointer", "-mfloat-abi=soft", "-fno-unwind-tables", "-fno-asynchronous-unwind-tables")
+	}
+	if strings.HasPrefix(target, "avr") {
+		// AVR defaults to C float and double both being 32-bit. This deviates
+		// from what most code (and certainly compiler-rt) expects. So we need
+		// to force the compiler to use 64-bit floating point numbers for
+		// double.
+		args = append(args, "-mdouble=64")
 	}
 	if strings.HasPrefix(target, "riscv32-") {
 		args = append(args, "-march=rv32imac", "-mabi=ilp32", "-fforce-enable-int128")
@@ -104,31 +170,59 @@ func (l *Library) load(target, cpu, tmpdir string) (job *compileJob, err error)
 	if strings.HasPrefix(target, "riscv64-") {
 		args = append(args, "-march=rv64gc", "-mabi=lp64")
 	}
+	if strings.HasPrefix(target, "xtensa") {
+		// Hack to work around an issue in the Xtensa port:
+		// https://github.com/espressif/llvm-project/issues/52
+		// Hopefully this will be fixed soon (LLVM 14).
+		args = append(args, "-D__ELF__")
+	}
+
+	var once sync.Once
 
 	// Create job to put all the object files in a single archive. This archive
 	// file is the (static) library file.
 	var objs []string
-	arpath := filepath.Join(dir, l.name+".a")
 	job = &compileJob{
-		description: "ar " + l.name + ".a",
-		result:      arpath,
+		description: "ar " + l.name + "/lib.a",
+		result:      filepath.Join(goenv.Get("GOCACHE"), outname, "lib.a"),
 		run: func(*compileJob) error {
+			defer once.Do(unlock)
+
 			// Create an archive of all object files.
-			err := makeArchive(arpath, objs)
+			f, err := ioutil.TempFile(outdir, "libc.a.tmp*")
+			if err != nil {
+				return err
+			}
+			err = makeArchive(f, objs)
+			if err != nil {
+				return err
+			}
+			err = f.Close()
+			if err != nil {
+				return err
+			}
+			err = os.Chmod(f.Name(), 0o644) // TempFile uses 0o600 by default
 			if err != nil {
 				return err
 			}
 			// Store this archive in the cache.
-			_, err = cacheStore(arpath, outfile, l.sourcePaths(target))
-			return err
+			return os.Rename(f.Name(), archiveFilePath)
 		},
 	}
 
+	sourceDir := l.sourceDir()
+
 	// Create jobs to compile all sources. These jobs are depended upon by the
 	// archive job above, so must be run first.
-	for _, srcpath := range l.sourcePaths(target) {
-		srcpath := srcpath // avoid concurrency issues by redefining inside the loop
-		objpath := filepath.Join(dir, filepath.Base(srcpath)+".o")
+	for _, path := range l.librarySources(target) {
+		// Strip leading "../" parts off the path.
+		cleanpath := path
+		for strings.HasPrefix(cleanpath, "../") {
+			cleanpath = cleanpath[3:]
+		}
+		srcpath := filepath.Join(sourceDir, path)
+		objpath := filepath.Join(dir, cleanpath+".o")
+		os.MkdirAll(filepath.Dir(objpath), 0o777)
 		objs = append(objs, objpath)
 		job.dependencies = append(job.dependencies, &compileJob{
 			description: "compile " + srcpath,
@@ -136,7 +230,7 @@ func (l *Library) load(target, cpu, tmpdir string) (job *compileJob, err error)
 				var compileArgs []string
 				compileArgs = append(compileArgs, args...)
 				compileArgs = append(compileArgs, "-o", objpath, srcpath)
-				err := runCCompiler("clang", compileArgs...)
+				err := runCCompiler(compileArgs...)
 				if err != nil {
 					return &commandError{"failed to build", srcpath, err}
 				}
@@ -145,5 +239,34 @@ func (l *Library) load(target, cpu, tmpdir string) (job *compileJob, err error)
 		})
 	}
 
-	return job, nil
+	// Create crt1.o job, if needed.
+	// Add this as a (fake) dependency to the ar file so it gets compiled.
+	// (It could be done in parallel with creating the ar file, but it probably
+	// won't make much of a difference in speed).
+	if l.crt1Source != "" {
+		srcpath := filepath.Join(sourceDir, l.crt1Source)
+		job.dependencies = append(job.dependencies, &compileJob{
+			description: "compile " + srcpath,
+			run: func(*compileJob) error {
+				var compileArgs []string
+				compileArgs = append(compileArgs, args...)
+				tmpfile, err := ioutil.TempFile(outdir, "crt1.o.tmp*")
+				if err != nil {
+					return err
+				}
+				tmpfile.Close()
+				compileArgs = append(compileArgs, "-o", tmpfile.Name(), srcpath)
+				err = runCCompiler(compileArgs...)
+				if err != nil {
+					return &commandError{"failed to build", srcpath, err}
+				}
+				return os.Rename(tmpfile.Name(), filepath.Join(outdir, "crt1.o"))
+			},
+		})
+	}
+
+	ok = true
+	return job, func() {
+		once.Do(unlock)
+	}, nil
 }

builder/lld.cpp

@@ -8,12 +8,22 @@ extern "C" {
 
 bool tinygo_link_elf(int argc, char **argv) {
 	std::vector<const char*> args(argv, argv + argc);
-	return lld::elf::link(args, false, llvm::outs(), llvm::errs());
+	return lld::elf::link(args, llvm::outs(), llvm::errs(), false, false);
+}
+
+bool tinygo_link_macho(int argc, char **argv) {
+	std::vector<const char*> args(argv, argv + argc);
+	return lld::macho::link(args, llvm::outs(), llvm::errs(), false, false);
+}
+
+bool tinygo_link_mingw(int argc, char **argv) {
+	std::vector<const char*> args(argv, argv + argc);
+	return lld::mingw::link(args, llvm::outs(), llvm::errs(), false, false);
 }
 
 bool tinygo_link_wasm(int argc, char **argv) {
 	std::vector<const char*> args(argv, argv + argc);
-	return lld::wasm::link(args, false, llvm::outs(), llvm::errs());
+	return lld::wasm::link(args, llvm::outs(), llvm::errs(), false, false);
 }
 
 } // external "C"

builder/mingw-w64.go

@@ -0,0 +1,92 @@
+package builder
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/tinygo-org/tinygo/goenv"
+)
+
+var MinGW = Library{
+	name: "mingw-w64",
+	makeHeaders: func(target, includeDir string) error {
+		// copy _mingw.h
+		srcDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib", "mingw-w64")
+		outf, err := os.Create(includeDir + "/_mingw.h")
+		if err != nil {
+			return err
+		}
+		defer outf.Close()
+		inf, err := os.Open(srcDir + "/mingw-w64-headers/crt/_mingw.h.in")
+		if err != nil {
+			return err
+		}
+		_, err = io.Copy(outf, inf)
+		return err
+	},
+	sourceDir: func() string { return "" }, // unused
+	cflags: func(target, headerPath string) []string {
+		// No flags necessary because there are no files to compile.
+		return nil
+	},
+	librarySources: func(target string) []string {
+		// We only use the UCRT DLL file. No source files necessary.
+		return nil
+	},
+}
+
+// makeMinGWExtraLibs returns a slice of jobs to import the correct .dll
+// libraries. This is done by converting input .def files to .lib files which
+// can then be linked as usual.
+//
+// TODO: cache the result. At the moment, it costs a few hundred milliseconds to
+// compile these files.
+func makeMinGWExtraLibs(tmpdir string) []*compileJob {
+	var jobs []*compileJob
+	root := goenv.Get("TINYGOROOT")
+	// Normally all the api-ms-win-crt-*.def files are all compiled to a single
+	// .lib file. But to simplify things, we're going to leave them as separate
+	// files.
+	for _, name := range []string{
+		"kernel32.def.in",
+		"api-ms-win-crt-conio-l1-1-0.def",
+		"api-ms-win-crt-convert-l1-1-0.def",
+		"api-ms-win-crt-environment-l1-1-0.def",
+		"api-ms-win-crt-filesystem-l1-1-0.def",
+		"api-ms-win-crt-heap-l1-1-0.def",
+		"api-ms-win-crt-locale-l1-1-0.def",
+		"api-ms-win-crt-math-l1-1-0.def.in",
+		"api-ms-win-crt-multibyte-l1-1-0.def",
+		"api-ms-win-crt-private-l1-1-0.def.in",
+		"api-ms-win-crt-process-l1-1-0.def",
+		"api-ms-win-crt-runtime-l1-1-0.def.in",
+		"api-ms-win-crt-stdio-l1-1-0.def",
+		"api-ms-win-crt-string-l1-1-0.def",
+		"api-ms-win-crt-time-l1-1-0.def",
+		"api-ms-win-crt-utility-l1-1-0.def",
+	} {
+		outpath := filepath.Join(tmpdir, filepath.Base(name)+".lib")
+		inpath := filepath.Join(root, "lib/mingw-w64/mingw-w64-crt/lib-common/"+name)
+		job := &compileJob{
+			description: "create lib file " + inpath,
+			result:      outpath,
+			run: func(job *compileJob) error {
+				defpath := inpath
+				if strings.HasSuffix(inpath, ".in") {
+					// .in files need to be preprocessed by a preprocessor (-E)
+					// first.
+					defpath = outpath + ".def"
+					err := runCCompiler("-E", "-x", "c", "-Wp,-w", "-P", "-DDEF_X64", "-o", defpath, inpath, "-I"+goenv.Get("TINYGOROOT")+"/lib/mingw-w64/mingw-w64-crt/def-include/")
+					if err != nil {
+						return err
+					}
+				}
+				return link("ld.lld", "-m", "i386pep", "-o", outpath, defpath)
+			},
+		}
+		jobs = append(jobs, job)
+	}
+	return jobs
+}

builder/musl.go

@@ -0,0 +1,164 @@
+package builder
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/goenv"
+)
+
+var Musl = Library{
+	name: "musl",
+	makeHeaders: func(target, includeDir string) error {
+		bits := filepath.Join(includeDir, "bits")
+		err := os.Mkdir(bits, 0777)
+		if err != nil {
+			return err
+		}
+
+		arch := compileopts.MuslArchitecture(target)
+		muslDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib", "musl")
+
+		// Create the file alltypes.h.
+		f, err := os.Create(filepath.Join(bits, "alltypes.h"))
+		if err != nil {
+			return err
+		}
+		infiles := []string{
+			filepath.Join(muslDir, "arch", arch, "bits", "alltypes.h.in"),
+			filepath.Join(muslDir, "include", "alltypes.h.in"),
+		}
+		for _, infile := range infiles {
+			data, err := ioutil.ReadFile(infile)
+			if err != nil {
+				return err
+			}
+			lines := strings.Split(string(data), "\n")
+			for _, line := range lines {
+				if strings.HasPrefix(line, "TYPEDEF ") {
+					matches := regexp.MustCompile(`TYPEDEF (.*) ([^ ]*);`).FindStringSubmatch(line)
+					value := matches[1]
+					name := matches[2]
+					line = fmt.Sprintf("#if defined(__NEED_%s) && !defined(__DEFINED_%s)\ntypedef %s %s;\n#define __DEFINED_%s\n#endif\n", name, name, value, name, name)
+				}
+				if strings.HasPrefix(line, "STRUCT ") {
+					matches := regexp.MustCompile(`STRUCT * ([^ ]*) (.*);`).FindStringSubmatch(line)
+					name := matches[1]
+					value := matches[2]
+					line = fmt.Sprintf("#if defined(__NEED_struct_%s) && !defined(__DEFINED_struct_%s)\nstruct %s %s;\n#define __DEFINED_struct_%s\n#endif\n", name, name, name, value, name)
+				}
+				f.WriteString(line + "\n")
+			}
+		}
+		f.Close()
+
+		// Create the file syscall.h.
+		f, err = os.Create(filepath.Join(bits, "syscall.h"))
+		if err != nil {
+			return err
+		}
+		data, err := ioutil.ReadFile(filepath.Join(muslDir, "arch", arch, "bits", "syscall.h.in"))
+		if err != nil {
+			return err
+		}
+		_, err = f.Write(bytes.ReplaceAll(data, []byte("__NR_"), []byte("SYS_")))
+		if err != nil {
+			return err
+		}
+		f.Close()
+
+		return nil
+	},
+	cflags: func(target, headerPath string) []string {
+		arch := compileopts.MuslArchitecture(target)
+		muslDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib/musl")
+		return []string{
+			"-std=c99",            // same as in musl
+			"-D_XOPEN_SOURCE=700", // same as in musl
+			// Musl triggers some warnings and we don't want to show any
+			// warnings while compiling (only errors or silence), so disable
+			// specific warnings that are triggered in musl.
+			"-Werror",
+			"-Wno-logical-op-parentheses",
+			"-Wno-bitwise-op-parentheses",
+			"-Wno-shift-op-parentheses",
+			"-Wno-ignored-attributes",
+			"-Wno-string-plus-int",
+			"-Qunused-arguments",
+			// Select include dirs. Don't include standard library includes
+			// (that would introduce host dependencies and other complications),
+			// but do include all the include directories expected by musl.
+			"-nostdlibinc",
+			"-I" + muslDir + "/arch/" + arch,
+			"-I" + muslDir + "/arch/generic",
+			"-I" + muslDir + "/src/include",
+			"-I" + muslDir + "/src/internal",
+			"-I" + headerPath,
+			"-I" + muslDir + "/include",
+			"-fno-stack-protector",
+		}
+	},
+	sourceDir: func() string { return filepath.Join(goenv.Get("TINYGOROOT"), "lib/musl/src") },
+	librarySources: func(target string) []string {
+		arch := compileopts.MuslArchitecture(target)
+		globs := []string{
+			"env/*.c",
+			"errno/*.c",
+			"exit/*.c",
+			"internal/defsysinfo.c",
+			"internal/libc.c",
+			"internal/syscall_ret.c",
+			"internal/vdso.c",
+			"legacy/*.c",
+			"malloc/*.c",
+			"mman/*.c",
+			"signal/*.c",
+			"stdio/*.c",
+			"string/*.c",
+			"thread/" + arch + "/*.s",
+			"thread/" + arch + "/*.c",
+			"thread/*.c",
+			"time/*.c",
+			"unistd/*.c",
+		}
+
+		var sources []string
+		seenSources := map[string]struct{}{}
+		basepath := goenv.Get("TINYGOROOT") + "/lib/musl/src/"
+		for _, pattern := range globs {
+			matches, err := filepath.Glob(basepath + pattern)
+			if err != nil {
+				// From the documentation:
+				// > Glob ignores file system errors such as I/O errors reading
+				// > directories. The only possible returned error is
+				// > ErrBadPattern, when pattern is malformed.
+				// So the only possible error is when the (statically defined)
+				// pattern is wrong. In other words, a programming bug.
+				panic("could not glob source dirs: " + err.Error())
+			}
+			for _, match := range matches {
+				relpath, err := filepath.Rel(basepath, match)
+				if err != nil {
+					// Not sure if this is even possible.
+					panic(err)
+				}
+				// Make sure architecture specific files override generic files.
+				id := strings.ReplaceAll(relpath, "/"+arch+"/", "/")
+				if _, ok := seenSources[id]; ok {
+					// Already seen this file, skipping this (generic) file.
+					continue
+				}
+				seenSources[id] = struct{}{}
+				sources = append(sources, relpath)
+			}
+		}
+		return sources
+	},
+	crt1Source: "../crt/crt1.c", // lib/musl/crt/crt1.c
+}

builder/nrfutil.go

@@ -0,0 +1,27 @@
+package builder
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os/exec"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+)
+
+// https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrfutil%2FUG%2Fnrfutil%2Fnrfutil_intro.html
+
+func makeDFUFirmwareImage(options *compileopts.Options, infile, outfile string) error {
+	cmdLine := []string{"nrfutil", "pkg", "generate", "--hw-version", "52", "--sd-req", "0x0", "--debug-mode", "--application", infile, outfile}
+
+	if options.PrintCommands != nil {
+		options.PrintCommands(cmdLine[0], cmdLine[1:]...)
+	}
+
+	cmd := exec.Command(cmdLine[0], cmdLine[1:]...)
+	cmd.Stdout = ioutil.Discard
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("could not run nrfutil pkg generate: %w", err)
+	}
+	return nil
+}

builder/picolibc.go

@@ -1,6 +1,7 @@
 package builder
 
 import (
+	"os"
 	"path/filepath"
 
 	"github.com/tinygo-org/tinygo/goenv"
@@ -10,17 +11,134 @@ import (
 // based on newlib.
 var Picolibc = Library{
 	name: "picolibc",
-	cflags: func() []string {
-		picolibcDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib/picolibc/newlib/libc")
-		return []string{"-Werror", "-Wall", "-std=gnu11", "-D_COMPILING_NEWLIB", "-nostdlibinc", "-Xclang", "-internal-isystem", "-Xclang", picolibcDir + "/include", "-I" + picolibcDir + "/tinystdio", "-I" + goenv.Get("TINYGOROOT") + "/lib/picolibc-include"}
+	makeHeaders: func(target, includeDir string) error {
+		f, err := os.Create(filepath.Join(includeDir, "picolibc.h"))
+		if err != nil {
+			return err
+		}
+		return f.Close()
 	},
-	sourceDir: "lib/picolibc/newlib/libc",
-	sources: func(target string) []string {
+	cflags: func(target, headerPath string) []string {
+		picolibcDir := filepath.Join(goenv.Get("TINYGOROOT"), "lib/picolibc/newlib/libc")
+		return []string{
+			"-Werror",
+			"-Wall",
+			"-std=gnu11",
+			"-D_COMPILING_NEWLIB",
+			"-DHAVE_ALIAS_ATTRIBUTE",
+			"-DTINY_STDIO",
+			"-nostdlibinc",
+			"-isystem", picolibcDir + "/include",
+			"-I" + picolibcDir + "/tinystdio",
+			"-I" + headerPath,
+		}
+	},
+	sourceDir: func() string { return filepath.Join(goenv.Get("TINYGOROOT"), "lib/picolibc/newlib/libc") },
+	librarySources: func(target string) []string {
 		return picolibcSources
 	},
 }
 
 var picolibcSources = []string{
+	"../../../picolibc-stdio.c",
+
+	"tinystdio/asprintf.c",
+	"tinystdio/atod_engine.c",
+	"tinystdio/atod_ryu.c",
+	"tinystdio/atof_engine.c",
+	"tinystdio/atof_ryu.c",
+	//"tinystdio/atold_engine.c", // have_long_double and not long_double_equals_double
+	"tinystdio/clearerr.c",
+	"tinystdio/compare_exchange.c",
+	"tinystdio/dtoa_data.c",
+	"tinystdio/dtoa_engine.c",
+	"tinystdio/dtoa_ryu.c",
+	"tinystdio/ecvtbuf.c",
+	"tinystdio/ecvt.c",
+	"tinystdio/ecvt_data.c",
+	"tinystdio/ecvtfbuf.c",
+	"tinystdio/ecvtf.c",
+	"tinystdio/ecvtf_data.c",
+	"tinystdio/exchange.c",
+	//"tinystdio/fclose.c", // posix-io
+	"tinystdio/fcvtbuf.c",
+	"tinystdio/fcvt.c",
+	"tinystdio/fcvtfbuf.c",
+	"tinystdio/fcvtf.c",
+	"tinystdio/fdevopen.c",
+	//"tinystdio/fdopen.c", // posix-io
+	"tinystdio/feof.c",
+	"tinystdio/ferror.c",
+	"tinystdio/fflush.c",
+	"tinystdio/fgetc.c",
+	"tinystdio/fgets.c",
+	"tinystdio/fileno.c",
+	"tinystdio/filestrget.c",
+	"tinystdio/filestrputalloc.c",
+	"tinystdio/filestrput.c",
+	//"tinystdio/fopen.c", // posix-io
+	"tinystdio/fprintf.c",
+	"tinystdio/fputc.c",
+	"tinystdio/fputs.c",
+	"tinystdio/fread.c",
+	"tinystdio/fscanf.c",
+	"tinystdio/fseek.c",
+	"tinystdio/ftell.c",
+	"tinystdio/ftoa_data.c",
+	"tinystdio/ftoa_engine.c",
+	"tinystdio/ftoa_ryu.c",
+	"tinystdio/fwrite.c",
+	"tinystdio/gcvtbuf.c",
+	"tinystdio/gcvt.c",
+	"tinystdio/gcvtfbuf.c",
+	"tinystdio/gcvtf.c",
+	"tinystdio/getchar.c",
+	"tinystdio/gets.c",
+	"tinystdio/matchcaseprefix.c",
+	"tinystdio/perror.c",
+	//"tinystdio/posixiob.c", // posix-io
+	//"tinystdio/posixio.c", // posix-io
+	"tinystdio/printf.c",
+	"tinystdio/putchar.c",
+	"tinystdio/puts.c",
+	"tinystdio/ryu_divpow2.c",
+	"tinystdio/ryu_log10.c",
+	"tinystdio/ryu_log2pow5.c",
+	"tinystdio/ryu_pow5bits.c",
+	"tinystdio/ryu_table.c",
+	"tinystdio/ryu_umul128.c",
+	"tinystdio/scanf.c",
+	"tinystdio/setbuf.c",
+	"tinystdio/setvbuf.c",
+	//"tinystdio/sflags.c", // posix-io
+	"tinystdio/snprintf.c",
+	"tinystdio/snprintfd.c",
+	"tinystdio/snprintff.c",
+	"tinystdio/sprintf.c",
+	"tinystdio/sprintfd.c",
+	"tinystdio/sprintff.c",
+	"tinystdio/sscanf.c",
+	"tinystdio/strfromd.c",
+	"tinystdio/strfromf.c",
+	"tinystdio/strtod.c",
+	"tinystdio/strtod_l.c",
+	"tinystdio/strtof.c",
+	//"tinystdio/strtold.c",   // have_long_double and not long_double_equals_double
+	//"tinystdio/strtold_l.c", // have_long_double and not long_double_equals_double
+	"tinystdio/ungetc.c",
+	"tinystdio/vasprintf.c",
+	"tinystdio/vfiprintf.c",
+	"tinystdio/vfiscanf.c",
+	"tinystdio/vfprintf.c",
+	"tinystdio/vfprintff.c",
+	"tinystdio/vfscanf.c",
+	"tinystdio/vfscanff.c",
+	"tinystdio/vprintf.c",
+	"tinystdio/vscanf.c",
+	"tinystdio/vsnprintf.c",
+	"tinystdio/vsprintf.c",
+	"tinystdio/vsscanf.c",
+
 	"string/bcmp.c",
 	"string/bcopy.c",
 	"string/bzero.c",

builder/sizes.go

@@ -1,16 +1,32 @@
 package builder
 
 import (
+	"bytes"
+	"debug/dwarf"
 	"debug/elf"
+	"debug/macho"
+	"debug/pe"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"regexp"
 	"sort"
 	"strings"
+
+	"github.com/aykevl/go-wasm"
+	"github.com/tinygo-org/tinygo/goenv"
 )
 
+// Set to true to print extra debug logs.
+const sizesDebug = false
+
 // programSize contains size statistics per package of a compiled program.
 type programSize struct {
-	Packages map[string]*packageSize
-	Sum      *packageSize
+	Packages map[string]packageSize
 	Code     uint64
+	ROData   uint64
 	Data     uint64
 	BSS      uint64
 }
@@ -26,6 +42,16 @@ func (ps *programSize) sortedPackageNames() []string {
 	return names
 }
 
+// Flash usage in regular microcontrollers.
+func (ps *programSize) Flash() uint64 {
+	return ps.Code + ps.ROData + ps.Data
+}
+
+// Static RAM usage in regular microcontrollers.
+func (ps *programSize) RAM() uint64 {
+	return ps.Data + ps.BSS
+}
+
 // packageSize contains the size of a package, calculated from the linked object
 // file.
 type packageSize struct {
@@ -45,129 +71,659 @@ func (ps *packageSize) RAM() uint64 {
 	return ps.Data + ps.BSS
 }
 
-type symbolList []elf.Symbol
-
-func (l symbolList) Len() int {
-	return len(l)
+// A mapping of a single chunk of code or data to a file path.
+type addressLine struct {
+	Address    uint64
+	Length     uint64 // length of this chunk
+	File       string // file path as stored in DWARF
+	IsVariable bool   // true if this is a variable (or constant), false if it is code
 }
 
-func (l symbolList) Less(i, j int) bool {
-	bind_i := elf.ST_BIND(l[i].Info)
-	bind_j := elf.ST_BIND(l[j].Info)
-	if l[i].Value == l[j].Value && bind_i != elf.STB_WEAK && bind_j == elf.STB_WEAK {
-		// sort weak symbols after non-weak symbols
-		return true
+// Sections defined in the input file. This struct defines them in a
+// filetype-agnostic way but roughly follow the ELF types (.text, .data, .bss,
+// etc).
+type memorySection struct {
+	Type    memoryType
+	Address uint64
+	Size    uint64
+}
+
+type memoryType int
+
+const (
+	memoryCode memoryType = iota + 1
+	memoryData
+	memoryROData
+	memoryBSS
+	memoryStack
+)
+
+func (t memoryType) String() string {
+	return [...]string{
+		0:            "-",
+		memoryCode:   "code",
+		memoryData:   "data",
+		memoryROData: "rodata",
+		memoryBSS:    "bss",
+		memoryStack:  "stack",
+	}[t]
+}
+
+// Regular expressions to match particular symbol names. These are not stored as
+// DWARF variables because they have no mapping to source code global variables.
+var (
+	// Various globals that aren't a variable but nonetheless need to be stored
+	// somewhere:
+	//   alloc:  heap allocations during init interpretation
+	//   pack:   data created when storing a constant in an interface for example
+	//   string: buffer behind strings
+	packageSymbolRegexp = regexp.MustCompile(`\$(alloc|embedfsfiles|embedfsslice|embedslice|pack|string)(\.[0-9]+)?$`)
+
+	// Reflect sidetables. Created by the reflect lowering pass.
+	// See src/reflect/sidetables.go.
+	reflectDataRegexp = regexp.MustCompile(`^reflect\.[a-zA-Z]+Sidetable$`)
+)
+
+// readProgramSizeFromDWARF reads the source location for each line of code and
+// each variable in the program, as far as this is stored in the DWARF debug
+// information.
+func readProgramSizeFromDWARF(data *dwarf.Data, codeOffset uint64) ([]addressLine, error) {
+	r := data.Reader()
+	var lines []*dwarf.LineFile
+	var addresses []addressLine
+	for {
+		e, err := r.Next()
+		if err != nil {
+			return nil, err
+		}
+		if e == nil {
+			break
+		}
+		switch e.Tag {
+		case dwarf.TagCompileUnit:
+			// Found a compile unit.
+			// We can read the .debug_line section using it, which contains a
+			// mapping for most instructions to their file/line/column - even
+			// for inlined functions!
+			lr, err := data.LineReader(e)
+			if err != nil {
+				return nil, err
+			}
+			lines = lr.Files()
+			var lineEntry = dwarf.LineEntry{
+				EndSequence: true,
+			}
+
+			// Line tables are organized as sequences of line entries until an
+			// end sequence. A single line table can contain multiple such
+			// sequences. The last line entry is an EndSequence to indicate the
+			// end.
+			for {
+				// Read the next .debug_line entry.
+				prevLineEntry := lineEntry
+				err := lr.Next(&lineEntry)
+				if err != nil {
+					if err == io.EOF {
+						break
+					}
+					return nil, err
+				}
+
+				if prevLineEntry.EndSequence && lineEntry.Address == 0 {
+					// Tombstone value. This symbol has been removed, for
+					// example by the --gc-sections linker flag. It is still
+					// here in the debug information because the linker can't
+					// just remove this reference.
+					// Read until the next EndSequence so that this sequence is
+					// skipped.
+					// For more details, see (among others):
+					// https://reviews.llvm.org/D84825
+					for {
+						err := lr.Next(&lineEntry)
+						if err != nil {
+							return nil, err
+						}
+						if lineEntry.EndSequence {
+							break
+						}
+					}
+				}
+
+				if !prevLineEntry.EndSequence {
+					// The chunk describes the code from prevLineEntry to
+					// lineEntry.
+					line := addressLine{
+						Address: prevLineEntry.Address + codeOffset,
+						Length:  lineEntry.Address - prevLineEntry.Address,
+						File:    prevLineEntry.File.Name,
+					}
+					if line.Length != 0 {
+						addresses = append(addresses, line)
+					}
+				}
+			}
+		case dwarf.TagVariable:
+			// Global variable (or constant). Most of these are not actually
+			// stored in the binary, because they have been optimized out. Only
+			// the ones with a location are still present.
+			r.SkipChildren()
+
+			file := e.AttrField(dwarf.AttrDeclFile)
+			location := e.AttrField(dwarf.AttrLocation)
+			globalType := e.AttrField(dwarf.AttrType)
+			if file == nil || location == nil || globalType == nil {
+				// Doesn't contain the requested information.
+				continue
+			}
+
+			// Try to parse the location. While this could in theory be a very
+			// complex expression, usually it's just a DW_OP_addr opcode
+			// followed by an address.
+			locationCode := location.Val.([]uint8)
+			if locationCode[0] != 3 { // DW_OP_addr
+				continue
+			}
+			var addr uint64
+			switch len(locationCode) {
+			case 1 + 2:
+				addr = uint64(binary.LittleEndian.Uint16(locationCode[1:]))
+			case 1 + 4:
+				addr = uint64(binary.LittleEndian.Uint32(locationCode[1:]))
+			case 1 + 8:
+				addr = binary.LittleEndian.Uint64(locationCode[1:])
+			default:
+				continue // unknown address
+			}
+
+			// Parse the type of the global variable, which (importantly)
+			// contains the variable size. We're not interested in the type,
+			// only in the size.
+			typ, err := data.Type(globalType.Val.(dwarf.Offset))
+			if err != nil {
+				return nil, err
+			}
+
+			addresses = append(addresses, addressLine{
+				Address:    addr,
+				Length:     uint64(typ.Size()),
+				File:       lines[file.Val.(int64)].Name,
+				IsVariable: true,
+			})
+		default:
+			r.SkipChildren()
+		}
 	}
-	return l[i].Value < l[j].Value
-}
-
-func (l symbolList) Swap(i, j int) {
-	l[i], l[j] = l[j], l[i]
+	return addresses, nil
 }
 
 // loadProgramSize calculate a program/data size breakdown of each package for a
 // given ELF file.
-func loadProgramSize(path string) (*programSize, error) {
-	file, err := elf.Open(path)
+// If the file doesn't contain DWARF debug information, the returned program
+// size will still have valid summaries but won't have complete size information
+// per package.
+func loadProgramSize(path string, packagePathMap map[string]string) (*programSize, error) {
+	// Open the binary file.
+	f, err := os.Open(path)
 	if err != nil {
 		return nil, err
 	}
-	defer file.Close()
+	defer f.Close()
 
-	var sumCode uint64
-	var sumData uint64
-	var sumBSS uint64
-	for _, section := range file.Sections {
-		if section.Flags&elf.SHF_ALLOC == 0 {
-			continue
-		}
-		if section.Type != elf.SHT_PROGBITS && section.Type != elf.SHT_NOBITS {
-			continue
-		}
-		if section.Name == ".stack" {
-			// HACK: this works around a bug in ld.lld from LLVM 10. The linker
-			// marks sections with no input symbols (such as is the case for the
-			// .stack section) as SHT_PROGBITS instead of SHT_NOBITS. While it
-			// doesn't affect the generated binaries (.hex and .bin), it does
-			// affect the reported size.
-			// https://bugs.llvm.org/show_bug.cgi?id=45336
-			// https://reviews.llvm.org/D76981
-			// It has been merged in master, but it has not (yet) been
-			// backported to the LLVM 10 release branch.
-			sumBSS += section.Size
-		} else if section.Type == elf.SHT_NOBITS {
-			sumBSS += section.Size
-		} else if section.Flags&elf.SHF_EXECINSTR != 0 {
-			sumCode += section.Size
-		} else if section.Flags&elf.SHF_WRITE != 0 {
-			sumData += section.Size
-		}
-	}
+	// This stores all chunks of addresses found in the binary.
+	var addresses []addressLine
 
-	allSymbols, err := file.Symbols()
-	if err != nil {
-		return nil, err
-	}
-	symbols := make([]elf.Symbol, 0, len(allSymbols))
-	for _, symbol := range allSymbols {
-		symType := elf.ST_TYPE(symbol.Info)
-		if symbol.Size == 0 {
-			continue
-		}
-		if symType != elf.STT_FUNC && symType != elf.STT_OBJECT && symType != elf.STT_NOTYPE {
-			continue
-		}
-		if symbol.Section >= elf.SectionIndex(len(file.Sections)) {
-			continue
-		}
-		section := file.Sections[symbol.Section]
-		if section.Flags&elf.SHF_ALLOC == 0 {
-			continue
-		}
-		symbols = append(symbols, symbol)
-	}
-	sort.Sort(symbolList(symbols))
-
-	sizes := map[string]*packageSize{}
-	var lastSymbolValue uint64
-	for _, symbol := range symbols {
-		symType := elf.ST_TYPE(symbol.Info)
-		//bind := elf.ST_BIND(symbol.Info)
-		section := file.Sections[symbol.Section]
-		pkgName := "(bootstrap)"
-		symName := strings.TrimLeft(symbol.Name, "(*")
-		dot := strings.IndexByte(symName, '.')
-		if dot > 0 {
-			pkgName = symName[:dot]
-		}
-		pkgSize := sizes[pkgName]
-		if pkgSize == nil {
-			pkgSize = &packageSize{}
-			sizes[pkgName] = pkgSize
-		}
-		if lastSymbolValue != symbol.Value || lastSymbolValue == 0 {
-			if symType == elf.STT_FUNC {
-				pkgSize.Code += symbol.Size
-			} else if section.Flags&elf.SHF_WRITE != 0 {
-				if section.Type == elf.SHT_NOBITS {
-					pkgSize.BSS += symbol.Size
-				} else {
-					pkgSize.Data += symbol.Size
-				}
-			} else {
-				pkgSize.ROData += symbol.Size
+	// Load the binary file, which could be in a number of file formats.
+	var sections []memorySection
+	if file, err := elf.NewFile(f); err == nil {
+		// Read DWARF information. The error is intentionally ignored.
+		data, _ := file.DWARF()
+		if data != nil {
+			addresses, err = readProgramSizeFromDWARF(data, 0)
+			if err != nil {
+				// However, _do_ report an error here. Something must have gone
+				// wrong while trying to parse DWARF data.
+				return nil, err
 			}
 		}
-		lastSymbolValue = symbol.Value
+
+		// Read the ELF symbols for some more chunks of location information.
+		// Some globals (such as strings) aren't stored in the DWARF debug
+		// information and therefore need to be obtained in a different way.
+		allSymbols, err := file.Symbols()
+		if err != nil {
+			return nil, err
+		}
+		for _, symbol := range allSymbols {
+			symType := elf.ST_TYPE(symbol.Info)
+			if symbol.Size == 0 {
+				continue
+			}
+			if symType != elf.STT_FUNC && symType != elf.STT_OBJECT && symType != elf.STT_NOTYPE {
+				continue
+			}
+			if symbol.Section >= elf.SHN_LORESERVE {
+				// Not a regular section, so skip it.
+				// One example is elf.SHN_ABS, which is used for symbols
+				// declared with an absolute value such as the memset function
+				// on the ESP32 which is defined in the mask ROM.
+				continue
+			}
+			section := file.Sections[symbol.Section]
+			if section.Flags&elf.SHF_ALLOC == 0 {
+				continue
+			}
+			if packageSymbolRegexp.MatchString(symbol.Name) || reflectDataRegexp.MatchString(symbol.Name) {
+				addresses = append(addresses, addressLine{
+					Address:    symbol.Value,
+					Length:     symbol.Size,
+					File:       symbol.Name,
+					IsVariable: true,
+				})
+			}
+		}
+
+		// Load allocated sections.
+		for _, section := range file.Sections {
+			if section.Flags&elf.SHF_ALLOC == 0 {
+				continue
+			}
+			if section.Type == elf.SHT_NOBITS {
+				if section.Name == ".stack" {
+					// TinyGo emits stack sections on microcontroller using the
+					// ".stack" name.
+					// This is a bit ugly, but I don't think there is a way to
+					// mark the stack section in a linker script.
+					sections = append(sections, memorySection{
+						Address: section.Addr,
+						Size:    section.Size,
+						Type:    memoryStack,
+					})
+				} else {
+					// Regular .bss section.
+					sections = append(sections, memorySection{
+						Address: section.Addr,
+						Size:    section.Size,
+						Type:    memoryBSS,
+					})
+				}
+			} else if section.Type == elf.SHT_PROGBITS && section.Flags&elf.SHF_EXECINSTR != 0 {
+				// .text
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    section.Size,
+					Type:    memoryCode,
+				})
+			} else if section.Type == elf.SHT_PROGBITS && section.Flags&elf.SHF_WRITE != 0 {
+				// .data
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    section.Size,
+					Type:    memoryData,
+				})
+			} else if section.Type == elf.SHT_PROGBITS {
+				// .rodata
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    section.Size,
+					Type:    memoryROData,
+				})
+			}
+		}
+	} else if file, err := macho.NewFile(f); err == nil {
+		// TODO: read DWARF information. On MacOS, DWARF debug information isn't
+		// stored in the executable but stays in the object files. The
+		// executable does however contain the object file paths that contain
+		// debug information.
+
+		// Read segments, for use while reading through sections.
+		segments := map[string]*macho.Segment{}
+		for _, load := range file.Loads {
+			switch load := load.(type) {
+			case *macho.Segment:
+				segments[load.Name] = load
+			}
+		}
+
+		// Read MachO sections.
+		for _, section := range file.Sections {
+			sectionType := section.Flags & 0xff
+			sectionFlags := section.Flags >> 8
+			segment := segments[section.Seg]
+			// For the constants used here, see:
+			// https://github.com/llvm/llvm-project/blob/release/14.x/llvm/include/llvm/BinaryFormat/MachO.h
+			if sectionFlags&0x800000 != 0 { // S_ATTR_PURE_INSTRUCTIONS
+				// Section containing only instructions.
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    uint64(section.Size),
+					Type:    memoryCode,
+				})
+			} else if sectionType == 1 { // S_ZEROFILL
+				// Section filled with zeroes on demand.
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    uint64(section.Size),
+					Type:    memoryBSS,
+				})
+			} else if segment.Maxprot&0b011 == 0b001 { // --r (read-only data)
+				// Protection doesn't allow writes, so mark this section read-only.
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    uint64(section.Size),
+					Type:    memoryROData,
+				})
+			} else {
+				// The rest is assumed to be regular data.
+				sections = append(sections, memorySection{
+					Address: section.Addr,
+					Size:    uint64(section.Size),
+					Type:    memoryData,
+				})
+			}
+		}
+	} else if file, err := pe.NewFile(f); err == nil {
+		// Read DWARF information. The error is intentionally ignored.
+		data, _ := file.DWARF()
+		if data != nil {
+			addresses, err = readProgramSizeFromDWARF(data, 0)
+			if err != nil {
+				// However, _do_ report an error here. Something must have gone
+				// wrong while trying to parse DWARF data.
+				return nil, err
+			}
+		}
+
+		// Read COFF sections.
+		optionalHeader := file.OptionalHeader.(*pe.OptionalHeader64)
+		for _, section := range file.Sections {
+			// For more information:
+			// https://docs.microsoft.com/en-us/windows/win32/api/winnt/ns-winnt-image_section_header
+			const (
+				IMAGE_SCN_CNT_CODE             = 0x00000020
+				IMAGE_SCN_CNT_INITIALIZED_DATA = 0x00000040
+				IMAGE_SCN_MEM_DISCARDABLE      = 0x02000000
+				IMAGE_SCN_MEM_READ             = 0x40000000
+				IMAGE_SCN_MEM_WRITE            = 0x80000000
+			)
+			if section.Characteristics&IMAGE_SCN_MEM_DISCARDABLE != 0 {
+				// Debug sections, etc.
+				continue
+			}
+			address := uint64(section.VirtualAddress) + optionalHeader.ImageBase
+			if section.Characteristics&IMAGE_SCN_CNT_CODE != 0 {
+				// .text
+				sections = append(sections, memorySection{
+					Address: address,
+					Size:    uint64(section.VirtualSize),
+					Type:    memoryCode,
+				})
+			} else if section.Characteristics&IMAGE_SCN_CNT_INITIALIZED_DATA != 0 {
+				if section.Characteristics&IMAGE_SCN_MEM_WRITE != 0 {
+					// .data
+					sections = append(sections, memorySection{
+						Address: address,
+						Size:    uint64(section.Size),
+						Type:    memoryData,
+					})
+					if section.Size < section.VirtualSize {
+						// Equivalent of a .bss section.
+						// Note: because of how the PE/COFF format is
+						// structured, not all zero-initialized data is marked
+						// as such. A portion may be at the end of the .data
+						// section and is thus marked as initialized data.
+						sections = append(sections, memorySection{
+							Address: address + uint64(section.Size),
+							Size:    uint64(section.VirtualSize) - uint64(section.Size),
+							Type:    memoryBSS,
+						})
+					}
+				} else if section.Characteristics&IMAGE_SCN_MEM_READ != 0 {
+					// .rdata, .buildid, .pdata
+					sections = append(sections, memorySection{
+						Address: address,
+						Size:    uint64(section.VirtualSize),
+						Type:    memoryROData,
+					})
+				}
+			}
+		}
+	} else if file, err := wasm.Parse(f); err == nil {
+		// File is in WebAssembly format.
+
+		// Put code at a very high address, so that it won't conflict with the
+		// data in the memory section.
+		const codeOffset = 0x8000_0000_0000_0000
+
+		// Read DWARF information. The error is intentionally ignored.
+		data, err := file.DWARF()
+		if data != nil {
+			addresses, err = readProgramSizeFromDWARF(data, codeOffset)
+			if err != nil {
+				// However, _do_ report an error here. Something must have gone
+				// wrong while trying to parse DWARF data.
+				return nil, err
+			}
+		}
+
+		var linearMemorySize uint64
+		for _, section := range file.Sections {
+			switch section := section.(type) {
+			case *wasm.SectionCode:
+				sections = append(sections, memorySection{
+					Address: codeOffset,
+					Size:    uint64(section.Size()),
+					Type:    memoryCode,
+				})
+			case *wasm.SectionMemory:
+				// This value is used when processing *wasm.SectionData (which
+				// always comes after *wasm.SectionMemory).
+				linearMemorySize = uint64(section.Entries[0].Limits.Initial) * 64 * 1024
+			case *wasm.SectionData:
+				// Data sections contain initial values for linear memory.
+				// First load the list of data sections, and sort them by
+				// address for easier processing.
+				var dataSections []memorySection
+				for _, entry := range section.Entries {
+					address, err := wasm.Eval(bytes.NewBuffer(entry.Offset))
+					if err != nil {
+						return nil, fmt.Errorf("could not parse data section address: %w", err)
+					}
+					dataSections = append(dataSections, memorySection{
+						Address: uint64(address[0].(int32)),
+						Size:    uint64(len(entry.Data)),
+						Type:    memoryData,
+					})
+				}
+				sort.Slice(dataSections, func(i, j int) bool {
+					return dataSections[i].Address < dataSections[j].Address
+				})
+
+				// And now add all data sections for linear memory.
+				// Parts that are in the slice of data sections are added as
+				// memoryData, and parts that are not are added as memoryBSS.
+				addr := uint64(0)
+				for _, section := range dataSections {
+					if addr < section.Address {
+						sections = append(sections, memorySection{
+							Address: addr,
+							Size:    section.Address - addr,
+							Type:    memoryBSS,
+						})
+					}
+					if addr > section.Address {
+						// This might be allowed, I'm not sure.
+						// It certainly doesn't make a lot of sense.
+						return nil, fmt.Errorf("overlapping data section")
+					}
+					// addr == section.Address
+					sections = append(sections, section)
+					addr = section.Address + section.Size
+				}
+				if addr < linearMemorySize {
+					sections = append(sections, memorySection{
+						Address: addr,
+						Size:    linearMemorySize - addr,
+						Type:    memoryBSS,
+					})
+				}
+			}
+		}
+	} else {
+		return nil, fmt.Errorf("could not parse file: %w", err)
 	}
 
-	sum := &packageSize{}
+	// Sort the slice of address chunks by address, so that we can iterate
+	// through it to calculate section sizes.
+	sort.Slice(addresses, func(i, j int) bool {
+		if addresses[i].Address == addresses[j].Address {
+			// Very rarely, there might be duplicate addresses.
+			// If that happens, sort the largest chunks first.
+			return addresses[i].Length > addresses[j].Length
+		}
+		return addresses[i].Address < addresses[j].Address
+	})
+
+	// Now finally determine the binary/RAM size usage per package by going
+	// through each allocated section.
+	sizes := make(map[string]packageSize)
+	for _, section := range sections {
+		switch section.Type {
+		case memoryCode:
+			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
+				field := sizes[path]
+				if isVariable {
+					field.ROData += size
+				} else {
+					field.Code += size
+				}
+				sizes[path] = field
+			}, packagePathMap)
+		case memoryROData:
+			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
+				field := sizes[path]
+				field.ROData += size
+				sizes[path] = field
+			}, packagePathMap)
+		case memoryData:
+			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
+				field := sizes[path]
+				field.Data += size
+				sizes[path] = field
+			}, packagePathMap)
+		case memoryBSS:
+			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
+				field := sizes[path]
+				field.BSS += size
+				sizes[path] = field
+			}, packagePathMap)
+		case memoryStack:
+			// We store the C stack as a pseudo-package.
+			sizes["C stack"] = packageSize{
+				BSS: section.Size,
+			}
+		}
+	}
+
+	// ...and summarize the results.
+	program := &programSize{
+		Packages: sizes,
+	}
 	for _, pkg := range sizes {
-		sum.Code += pkg.Code
-		sum.ROData += pkg.ROData
-		sum.Data += pkg.Data
-		sum.BSS += pkg.BSS
+		program.Code += pkg.Code
+		program.ROData += pkg.ROData
+		program.Data += pkg.Data
+		program.BSS += pkg.BSS
 	}
-
-	return &programSize{Packages: sizes, Code: sumCode, Data: sumData, BSS: sumBSS, Sum: sum}, nil
+	return program, nil
+}
+
+// readSection determines for each byte in this section to which package it
+// belongs. It reports this usage through the addSize callback.
+func readSection(section memorySection, addresses []addressLine, addSize func(string, uint64, bool), packagePathMap map[string]string) {
+	// The addr variable tracks at which address we are while going through this
+	// section. We start at the beginning.
+	addr := section.Address
+	sectionEnd := section.Address + section.Size
+	if sizesDebug {
+		fmt.Printf("%08x..%08x %5d: %s\n", addr, sectionEnd, section.Size, section.Type)
+	}
+	for _, line := range addresses {
+		if line.Address < section.Address || line.Address+line.Length > sectionEnd {
+			// Check that this line is entirely within the section.
+			// Don't bother dealing with line entries that cross sections (that
+			// seems rather unlikely anyway).
+			continue
+		}
+		if addr < line.Address {
+			// There is a gap: there is a space between the current and the
+			// previous line entry.
+			addSize("(unknown)", line.Address-addr, false)
+			if sizesDebug {
+				fmt.Printf("%08x..%08x %5d:  unknown (gap)\n", addr, line.Address, line.Address-addr)
+			}
+		}
+		if addr > line.Address+line.Length {
+			// The current line is already covered by a previous line entry.
+			// Simply skip it.
+			continue
+		}
+		// At this point, addr falls within the current line (probably at the
+		// start).
+		length := line.Length
+		if addr > line.Address {
+			// There is some overlap: the previous line entry already covered
+			// part of this line entry. So reduce the length to add to the
+			// remaining bit of the line entry.
+			length = line.Length - (addr - line.Address)
+		}
+		// Finally, mark this chunk of memory as used by the given package.
+		addSize(findPackagePath(line.File, packagePathMap), length, line.IsVariable)
+		addr = line.Address + line.Length
+	}
+	if addr < sectionEnd {
+		// There is a gap at the end of the section.
+		addSize("(unknown)", sectionEnd-addr, false)
+		if sizesDebug {
+			fmt.Printf("%08x..%08x %5d:  unknown (end)\n", addr, sectionEnd, sectionEnd-addr)
+		}
+	}
+}
+
+// findPackagePath returns the Go package (or a pseudo package) for the given
+// path. It uses some heuristics, for example for some C libraries.
+func findPackagePath(path string, packagePathMap map[string]string) string {
+	// Check whether this path is part of one of the compiled packages.
+	packagePath, ok := packagePathMap[filepath.Dir(path)]
+	if !ok {
+		if strings.HasPrefix(path, filepath.Join(goenv.Get("TINYGOROOT"), "lib")) {
+			// Emit C libraries (in the lib subdirectory of TinyGo) as a single
+			// package, with a "C" prefix. For example: "C compiler-rt" for the
+			// compiler runtime library from LLVM.
+			packagePath = "C " + strings.Split(strings.TrimPrefix(path, filepath.Join(goenv.Get("TINYGOROOT"), "lib")), string(os.PathSeparator))[1]
+		} else if packageSymbolRegexp.MatchString(path) {
+			// Parse symbol names like main$alloc or runtime$string.
+			packagePath = path[:strings.LastIndex(path, "$")]
+		} else if reflectDataRegexp.MatchString(path) {
+			// Parse symbol names like reflect.structTypesSidetable.
+			packagePath = "Go reflect data"
+		} else if path == "<Go interface assert>" {
+			// Interface type assert, generated by the interface lowering pass.
+			packagePath = "Go interface assert"
+		} else if path == "<Go interface method>" {
+			// Interface method wrapper (switch over all concrete types),
+			// generated by the interface lowering pass.
+			packagePath = "Go interface method"
+		} else if path == "<stdin>" {
+			// This can happen when the source code (in Go) doesn't have a
+			// source file and uses "-" as the location. Somewhere this is
+			// converted to "<stdin>".
+			// Convert this back to the "-" string. Eventually, this should be
+			// fixed in the compiler.
+			packagePath = "-"
+		} else {
+			// This is some other path. Not sure what it is, so just emit its directory.
+			packagePath = filepath.Dir(path) // fallback
+		}
+	}
+	return packagePath
 }

builder/tools-builtin.go

@@ -1,3 +1,4 @@
+//go:build byollvm
 // +build byollvm
 
 package builder
@@ -13,6 +14,8 @@ import (
 #include <stdlib.h>
 bool tinygo_clang_driver(int argc, char **argv);
 bool tinygo_link_elf(int argc, char **argv);
+bool tinygo_link_macho(int argc, char **argv);
+bool tinygo_link_mingw(int argc, char **argv);
 bool tinygo_link_wasm(int argc, char **argv);
 */
 import "C"
@@ -24,6 +27,15 @@ const hasBuiltinTools = true
 // This version actually runs the tools because TinyGo was compiled while
 // linking statically with LLVM (with the byollvm build tag).
 func RunTool(tool string, args ...string) error {
+	linker := "elf"
+	if tool == "ld.lld" && len(args) >= 2 {
+		if args[0] == "-m" && args[1] == "i386pep" {
+			linker = "mingw"
+		} else if args[0] == "-flavor" {
+			linker = args[1]
+			args = args[2:]
+		}
+	}
 	args = append([]string{"tinygo:" + tool}, args...)
 
 	var cflag *C.char
@@ -41,7 +53,16 @@ func RunTool(tool string, args ...string) error {
 	case "clang":
 		ok = C.tinygo_clang_driver(C.int(len(args)), (**C.char)(buf))
 	case "ld.lld":
-		ok = C.tinygo_link_elf(C.int(len(args)), (**C.char)(buf))
+		switch linker {
+		case "darwin":
+			ok = C.tinygo_link_macho(C.int(len(args)), (**C.char)(buf))
+		case "elf":
+			ok = C.tinygo_link_elf(C.int(len(args)), (**C.char)(buf))
+		case "mingw":
+			ok = C.tinygo_link_mingw(C.int(len(args)), (**C.char)(buf))
+		default:
+			return errors.New("unknown linker: " + linker)
+		}
 	case "wasm-ld":
 		ok = C.tinygo_link_wasm(C.int(len(args)), (**C.char)(buf))
 	default:

builder/tools-external.go

@@ -1,3 +1,4 @@
+//go:build !byollvm
 // +build !byollvm
 
 package builder

builder/tools.go

@@ -9,8 +9,8 @@ import (
 )
 
 // runCCompiler invokes a C compiler with the given arguments.
-func runCCompiler(command string, flags ...string) error {
-	if hasBuiltinTools && command == "clang" {
+func runCCompiler(flags ...string) error {
+	if hasBuiltinTools {
 		// Compile this with the internal Clang compiler.
 		headerPath := getClangHeaderPath(goenv.Get("TINYGOROOT"))
 		if headerPath == "" {
@@ -23,17 +23,8 @@ func runCCompiler(command string, flags ...string) error {
 		return cmd.Run()
 	}
 
-	// Running some other compiler. Maybe it has been defined in the
-	// commands map (unlikely).
-	if cmdNames, ok := commands[command]; ok {
-		return execCommand(cmdNames, flags...)
-	}
-
-	// Alternatively, run the compiler directly.
-	cmd := exec.Command(command, flags...)
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	return cmd.Run()
+	// Compile this with an external invocation of the Clang compiler.
+	return execCommand("clang", flags...)
 }
 
 // link invokes a linker with the given name and flags.
@@ -47,8 +38,8 @@ func link(linker string, flags ...string) error {
 	}
 
 	// Fall back to external command.
-	if cmdNames, ok := commands[linker]; ok {
-		return execCommand(cmdNames, flags...)
+	if _, ok := commands[linker]; ok {
+		return execCommand(linker, flags...)
 	}
 
 	cmd := exec.Command(linker, flags...)

builder/uf2.go

@@ -141,11 +141,13 @@ func split(input []byte, limit int) [][]byte {
 	var block []byte
 	output := make([][]byte, 0, len(input)/limit+1)
 	for len(input) >= limit {
+		// add all blocks
 		block, input = input[:limit], input[limit:]
 		output = append(output, block)
 	}
 	if len(input) > 0 {
-		output = append(output, input[:len(input)])
+		// add remaining block (that isn't full sized)
+		output = append(output, input)
 	}
 	return output
 }

cgo/cgo_test.go

@@ -12,7 +12,6 @@ import (
 	"go/types"
 	"io/ioutil"
 	"path/filepath"
-	"regexp"
 	"runtime"
 	"strings"
 	"testing"
@@ -25,21 +24,20 @@ var flagUpdate = flag.Bool("update", false, "Update images based on test output.
 // platforms and Go versions.
 func normalizeResult(result string) string {
 	actual := strings.ReplaceAll(result, "\r\n", "\n")
-
-	// Make sure all functions are wrapped, even those that would otherwise be
-	// single-line functions. This is necessary because Go 1.14 changed the way
-	// such functions are wrapped and it's important to have consistent test
-	// results.
-	re := regexp.MustCompile(`func \((.+)\)( .*?) +{ (.+) }`)
-	actual = re.ReplaceAllString(actual, "func ($1)$2 {\n\t$3\n}")
-
 	return actual
 }
 
 func TestCGo(t *testing.T) {
-	var cflags = []string{"--target=armv6m-none-eabi"}
+	var cflags = []string{"--target=armv6m-unknown-unknown-eabi"}
 
-	for _, name := range []string{"basic", "errors", "types", "flags", "const"} {
+	for _, name := range []string{
+		"basic",
+		"errors",
+		"types",
+		"symbols",
+		"flags",
+		"const",
+	} {
 		name := name // avoid a race condition
 		t.Run(name, func(t *testing.T) {
 			// Skip tests that require specific Go version.
@@ -65,7 +63,7 @@ func TestCGo(t *testing.T) {
 			}
 
 			// Process the AST with CGo.
-			cgoAST, _, _, _, cgoErrors := Process([]*ast.File{f}, "testdata", fset, cflags)
+			cgoAST, _, _, _, _, cgoErrors := Process([]*ast.File{f}, "testdata", fset, cflags, "")
 
 			// Check the AST for type errors.
 			var typecheckErrors []error
@@ -105,7 +103,7 @@ func TestCGo(t *testing.T) {
 			if err != nil {
 				t.Errorf("could not write out CGo AST: %v", err)
 			}
-			actual := normalizeResult(string(buf.Bytes()))
+			actual := normalizeResult(buf.String())
 
 			// Read the file with the expected output, to compare against.
 			outfile := filepath.Join("testdata", name+".out.go")

cgo/const.go

@@ -11,105 +11,184 @@ import (
 	"strings"
 )
 
+var (
+	prefixParseFns map[token.Token]func(*tokenizer) (ast.Expr, *scanner.Error)
+	precedences    = map[token.Token]int{
+		token.ADD: precedenceAdd,
+		token.SUB: precedenceAdd,
+		token.MUL: precedenceMul,
+		token.QUO: precedenceMul,
+		token.REM: precedenceMul,
+	}
+)
+
+const (
+	precedenceLowest = iota + 1
+	precedenceAdd
+	precedenceMul
+	precedencePrefix
+)
+
+func init() {
+	// This must be done in an init function to avoid an initialization order
+	// failure.
+	prefixParseFns = map[token.Token]func(*tokenizer) (ast.Expr, *scanner.Error){
+		token.IDENT:  parseIdent,
+		token.INT:    parseBasicLit,
+		token.FLOAT:  parseBasicLit,
+		token.STRING: parseBasicLit,
+		token.CHAR:   parseBasicLit,
+		token.LPAREN: parseParenExpr,
+		token.SUB:    parseUnaryExpr,
+	}
+}
+
 // parseConst parses the given string as a C constant.
 func parseConst(pos token.Pos, fset *token.FileSet, value string) (ast.Expr, *scanner.Error) {
 	t := newTokenizer(pos, fset, value)
-	expr, err := parseConstExpr(t)
-	if t.token != token.EOF {
+	expr, err := parseConstExpr(t, precedenceLowest)
+	t.Next()
+	if t.curToken != token.EOF {
 		return nil, &scanner.Error{
-			Pos: t.fset.Position(t.pos),
-			Msg: "unexpected token " + t.token.String(),
+			Pos: t.fset.Position(t.curPos),
+			Msg: "unexpected token " + t.curToken.String() + ", expected end of expression",
 		}
 	}
 	return expr, err
 }
 
 // parseConstExpr parses a stream of C tokens to a Go expression.
-func parseConstExpr(t *tokenizer) (ast.Expr, *scanner.Error) {
-	switch t.token {
-	case token.LPAREN:
-		lparen := t.pos
-		t.Next()
-		x, err := parseConstExpr(t)
-		if err != nil {
-			return nil, err
-		}
-		if t.token != token.RPAREN {
-			return nil, unexpectedToken(t, token.RPAREN)
-		}
-		expr := &ast.ParenExpr{
-			Lparen: lparen,
-			X:      x,
-			Rparen: t.pos,
-		}
-		t.Next()
-		return expr, nil
-	case token.INT, token.FLOAT, token.STRING, token.CHAR:
-		expr := &ast.BasicLit{
-			ValuePos: t.pos,
-			Kind:     t.token,
-			Value:    t.value,
-		}
-		t.Next()
-		return expr, nil
-	case token.IDENT:
-		expr := &ast.Ident{
-			NamePos: t.pos,
-			Name:    "C." + t.value,
-		}
-		t.Next()
-		return expr, nil
-	case token.EOF:
+func parseConstExpr(t *tokenizer, precedence int) (ast.Expr, *scanner.Error) {
+	if t.curToken == token.EOF {
 		return nil, &scanner.Error{
-			Pos: t.fset.Position(t.pos),
+			Pos: t.fset.Position(t.curPos),
 			Msg: "empty constant",
 		}
-	default:
+	}
+	prefix := prefixParseFns[t.curToken]
+	if prefix == nil {
 		return nil, &scanner.Error{
-			Pos: t.fset.Position(t.pos),
-			Msg: fmt.Sprintf("unexpected token %s", t.token),
+			Pos: t.fset.Position(t.curPos),
+			Msg: fmt.Sprintf("unexpected token %s", t.curToken),
 		}
 	}
+	leftExpr, err := prefix(t)
+
+	for t.peekToken != token.EOF && precedence < precedences[t.peekToken] {
+		switch t.peekToken {
+		case token.ADD, token.SUB, token.MUL, token.QUO, token.REM:
+			t.Next()
+			leftExpr, err = parseBinaryExpr(t, leftExpr)
+		}
+	}
+
+	return leftExpr, err
+}
+
+func parseIdent(t *tokenizer) (ast.Expr, *scanner.Error) {
+	return &ast.Ident{
+		NamePos: t.curPos,
+		Name:    "C." + t.curValue,
+	}, nil
+}
+
+func parseBasicLit(t *tokenizer) (ast.Expr, *scanner.Error) {
+	return &ast.BasicLit{
+		ValuePos: t.curPos,
+		Kind:     t.curToken,
+		Value:    t.curValue,
+	}, nil
+}
+
+func parseParenExpr(t *tokenizer) (ast.Expr, *scanner.Error) {
+	lparen := t.curPos
+	t.Next()
+	x, err := parseConstExpr(t, precedenceLowest)
+	if err != nil {
+		return nil, err
+	}
+	t.Next()
+	if t.curToken != token.RPAREN {
+		return nil, unexpectedToken(t, token.RPAREN)
+	}
+	expr := &ast.ParenExpr{
+		Lparen: lparen,
+		X:      x,
+		Rparen: t.curPos,
+	}
+	return expr, nil
+}
+
+func parseBinaryExpr(t *tokenizer, left ast.Expr) (ast.Expr, *scanner.Error) {
+	expression := &ast.BinaryExpr{
+		X:     left,
+		Op:    t.curToken,
+		OpPos: t.curPos,
+	}
+	precedence := precedences[t.curToken]
+	t.Next()
+	right, err := parseConstExpr(t, precedence)
+	expression.Y = right
+	return expression, err
+}
+
+func parseUnaryExpr(t *tokenizer) (ast.Expr, *scanner.Error) {
+	expression := &ast.UnaryExpr{
+		OpPos: t.curPos,
+		Op:    t.curToken,
+	}
+	t.Next()
+	x, err := parseConstExpr(t, precedencePrefix)
+	expression.X = x
+	return expression, err
 }
 
 // unexpectedToken returns an error of the form "unexpected token FOO, expected
 // BAR".
 func unexpectedToken(t *tokenizer, expected token.Token) *scanner.Error {
 	return &scanner.Error{
-		Pos: t.fset.Position(t.pos),
-		Msg: fmt.Sprintf("unexpected token %s, expected %s", t.token, expected),
+		Pos: t.fset.Position(t.curPos),
+		Msg: fmt.Sprintf("unexpected token %s, expected %s", t.curToken, expected),
 	}
 }
 
 // tokenizer reads C source code and converts it to Go tokens.
 type tokenizer struct {
-	pos   token.Pos
-	fset  *token.FileSet
-	token token.Token
-	value string
-	buf   string
+	curPos, peekPos     token.Pos
+	fset                *token.FileSet
+	curToken, peekToken token.Token
+	curValue, peekValue string
+	buf                 string
 }
 
 // newTokenizer initializes a new tokenizer, positioned at the first token in
 // the string.
 func newTokenizer(start token.Pos, fset *token.FileSet, buf string) *tokenizer {
 	t := &tokenizer{
-		pos:   start,
-		fset:  fset,
-		buf:   buf,
-		token: token.ILLEGAL,
+		peekPos:   start,
+		fset:      fset,
+		buf:       buf,
+		peekToken: token.ILLEGAL,
 	}
-	t.Next() // Parse the first token.
+	// Parse the first two tokens (cur and peek).
+	t.Next()
+	t.Next()
 	return t
 }
 
 // Next consumes the next token in the stream. There is no return value, read
 // the next token from the pos, token and value properties.
 func (t *tokenizer) Next() {
-	t.pos += token.Pos(len(t.value))
+	// The previous peek is now the current token.
+	t.curPos = t.peekPos
+	t.curToken = t.peekToken
+	t.curValue = t.peekValue
+
+	// Parse the next peek token.
+	t.peekPos += token.Pos(len(t.curValue))
 	for {
 		if len(t.buf) == 0 {
-			t.token = token.EOF
+			t.peekToken = token.EOF
 			return
 		}
 		c := t.buf[0]
@@ -118,17 +197,28 @@ func (t *tokenizer) Next() {
 			// Skip whitespace.
 			// Based on this source, not sure whether it represents C whitespace:
 			// https://en.cppreference.com/w/cpp/string/byte/isspace
-			t.pos++
+			t.peekPos++
 			t.buf = t.buf[1:]
-		case c == '(' || c == ')':
+		case c == '(' || c == ')' || c == '+' || c == '-' || c == '*' || c == '/' || c == '%':
 			// Single-character tokens.
+			// TODO: ++ (increment) and -- (decrement) operators.
 			switch c {
 			case '(':
-				t.token = token.LPAREN
+				t.peekToken = token.LPAREN
 			case ')':
-				t.token = token.RPAREN
+				t.peekToken = token.RPAREN
+			case '+':
+				t.peekToken = token.ADD
+			case '-':
+				t.peekToken = token.SUB
+			case '*':
+				t.peekToken = token.MUL
+			case '/':
+				t.peekToken = token.QUO
+			case '%':
+				t.peekToken = token.REM
 			}
-			t.value = t.buf[:1]
+			t.peekValue = t.buf[:1]
 			t.buf = t.buf[1:]
 			return
 		case c >= '0' && c <= '9':
@@ -146,17 +236,17 @@ func (t *tokenizer) Next() {
 					break
 				}
 			}
-			t.value = t.buf[:tokenLen]
+			t.peekValue = t.buf[:tokenLen]
 			t.buf = t.buf[tokenLen:]
 			if hasDot {
 				// Integer constants are more complicated than this but this is
 				// a close approximation.
 				// https://en.cppreference.com/w/cpp/language/integer_literal
-				t.token = token.FLOAT
-				t.value = strings.TrimRight(t.value, "f")
+				t.peekToken = token.FLOAT
+				t.peekValue = strings.TrimRight(t.peekValue, "f")
 			} else {
-				t.token = token.INT
-				t.value = strings.TrimRight(t.value, "uUlL")
+				t.peekToken = token.INT
+				t.peekValue = strings.TrimRight(t.peekValue, "uUlL")
 			}
 			return
 		case c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z' || c == '_':
@@ -170,9 +260,9 @@ func (t *tokenizer) Next() {
 					break
 				}
 			}
-			t.value = t.buf[:tokenLen]
+			t.peekValue = t.buf[:tokenLen]
 			t.buf = t.buf[tokenLen:]
-			t.token = token.IDENT
+			t.peekToken = token.IDENT
 			return
 		case c == '"':
 			// String constant. Find the first '"' character that is not
@@ -188,8 +278,8 @@ func (t *tokenizer) Next() {
 					escape = c == '\\'
 				}
 			}
-			t.token = token.STRING
-			t.value = t.buf[:tokenLen]
+			t.peekToken = token.STRING
+			t.peekValue = t.buf[:tokenLen]
 			t.buf = t.buf[tokenLen:]
 			return
 		case c == '\'':
@@ -206,12 +296,12 @@ func (t *tokenizer) Next() {
 					escape = c == '\\'
 				}
 			}
-			t.token = token.CHAR
-			t.value = t.buf[:tokenLen]
+			t.peekToken = token.CHAR
+			t.peekValue = t.buf[:tokenLen]
 			t.buf = t.buf[tokenLen:]
 			return
 		default:
-			t.token = token.ILLEGAL
+			t.peekToken = token.ILLEGAL
 			return
 		}
 	}

cgo/const_test.go

@@ -18,7 +18,7 @@ func TestParseConst(t *testing.T) {
 		{`(5)`, `(5)`},
 		{`(((5)))`, `(5)`},
 		{`)`, `error: 1:1: unexpected token )`},
-		{`5)`, `error: 1:2: unexpected token )`},
+		{`5)`, `error: 1:2: unexpected token ), expected end of expression`},
 		{"  \t)", `error: 1:4: unexpected token )`},
 		{`5.8f`, `5.8`},
 		{`foo`, `C.foo`},
@@ -30,7 +30,24 @@ func TestParseConst(t *testing.T) {
 		{`'a'`, `'a'`},
 		{`0b10`, `0b10`},
 		{`0x1234_5678`, `0x1234_5678`},
-		{`5 5`, `error: 1:3: unexpected token INT`}, // test for a bugfix
+		{`5 5`, `error: 1:3: unexpected token INT, expected end of expression`}, // test for a bugfix
+		// Binary operators.
+		{`5+5`, `5 + 5`},
+		{`5-5`, `5 - 5`},
+		{`5*5`, `5 * 5`},
+		{`5/5`, `5 / 5`},
+		{`5%5`, `5 % 5`},
+		{`(5/5)`, `(5 / 5)`},
+		{`1 - 2`, `1 - 2`},
+		{`1 - 2 + 3`, `1 - 2 + 3`},
+		{`1 - 2 * 3`, `1 - 2*3`},
+		{`(1 - 2) * 3`, `(1 - 2) * 3`},
+		{`1 * 2 - 3`, `1*2 - 3`},
+		{`1 * (2 - 3)`, `1 * (2 - 3)`},
+		// Unary operators.
+		{`-5`, `-5`},
+		{`-5-2`, `-5 - 2`},
+		{`5 - - 2`, `5 - -2`},
 	} {
 		fset := token.NewFileSet()
 		startPos := fset.AddFile("", -1, 1000).Pos(0)

cgo/libclang.go

@@ -16,7 +16,7 @@ import (
 )
 
 /*
-#include <clang-c/Index.h> // if this fails, install libclang-10-dev
+#include <clang-c/Index.h> // If this fails, libclang headers aren't available. Please take a look here: https://tinygo.org/docs/guides/build/
 #include <stdlib.h>
 #include <stdint.h>
 
@@ -72,17 +72,18 @@ var diagnosticSeverity = [...]string{
 	C.CXDiagnostic_Fatal:   "fatal",
 }
 
-func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename string, posLine int) {
+// Alias so that cgo.go (which doesn't import Clang related stuff and is in
+// theory decoupled from Clang) can also use this type.
+type clangCursor = C.GoCXCursor
+
+func (f *cgoFile) readNames(fragment string, cflags []string, filename string, callback func(map[string]clangCursor)) {
 	index := C.clang_createIndex(0, 0)
 	defer C.clang_disposeIndex(index)
 
 	// pretend to be a .c file
-	filenameC := C.CString(posFilename + "!cgo.c")
+	filenameC := C.CString(filename + "!cgo.c")
 	defer C.free(unsafe.Pointer(filenameC))
 
-	// fix up error locations
-	fragment = fmt.Sprintf("# %d %#v\n", posLine+1, posFilename) + fragment
-
 	fragmentC := C.CString(fragment)
 	defer C.free(unsafe.Pointer(fragmentC))
 
@@ -122,8 +123,8 @@ func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename
 			spelling := getString(C.clang_getDiagnosticSpelling(diagnostic))
 			severity := diagnosticSeverity[C.clang_getDiagnosticSeverity(diagnostic)]
 			location := C.clang_getDiagnosticLocation(diagnostic)
-			pos := p.getClangLocationPosition(location, unit)
-			p.addError(pos, severity+": "+spelling)
+			pos := f.getClangLocationPosition(location, unit)
+			f.addError(pos, severity+": "+spelling)
 		}
 		for i := 0; i < numDiagnostics; i++ {
 			diagnostic := C.clang_getDiagnostic(unit, C.uint(i))
@@ -138,7 +139,7 @@ func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename
 	}
 
 	// Extract information required by CGo.
-	ref := storedRefs.Put(p)
+	ref := storedRefs.Put(f)
 	defer storedRefs.Remove(ref)
 	cursor := C.tinygo_clang_getTranslationUnitCursor(unit)
 	C.tinygo_clang_visitChildren(cursor, C.CXCursorVisitor(C.tinygo_clang_globals_visitor), C.CXClientData(ref))
@@ -158,35 +159,64 @@ func (p *cgoPackage) parseFragment(fragment string, cflags []string, posFilename
 		data := (*[1 << 24]byte)(unsafe.Pointer(rawData))[:size]
 
 		// Hash the contents if it isn't hashed yet.
-		if _, ok := p.visitedFiles[path]; !ok {
+		if _, ok := f.visitedFiles[path]; !ok {
 			// already stored
 			sum := sha512.Sum512_224(data)
-			p.visitedFiles[path] = sum[:]
+			f.visitedFiles[path] = sum[:]
 		}
 	}
 	inclusionCallbackRef := storedRefs.Put(inclusionCallback)
 	defer storedRefs.Remove(inclusionCallbackRef)
 	C.clang_getInclusions(unit, C.CXInclusionVisitor(C.tinygo_clang_inclusion_visitor), C.CXClientData(inclusionCallbackRef))
+
+	// Do all the C AST operations inside a callback. This makes sure that
+	// libclang related memory is only freed after it is not necessary anymore.
+	callback(f.names)
 }
 
-//export tinygo_clang_globals_visitor
-func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClientData) C.int {
-	p := storedRefs.Get(unsafe.Pointer(client_data)).(*cgoPackage)
+// Convert the AST node under the given Clang cursor to a Go AST node and return
+// it.
+func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, *elaboratedTypeInfo) {
 	kind := C.tinygo_clang_getCursorKind(c)
-	pos := p.getCursorPosition(c)
+	pos := f.getCursorPosition(c)
 	switch kind {
 	case C.CXCursor_FunctionDecl:
-		name := getString(C.tinygo_clang_getCursorSpelling(c))
-		if _, required := p.missingSymbols[name]; !required {
-			return C.CXChildVisit_Continue
-		}
 		cursorType := C.tinygo_clang_getCursorType(c)
 		numArgs := int(C.tinygo_clang_Cursor_getNumArguments(c))
-		fn := &functionInfo{
-			pos:      pos,
-			variadic: C.clang_isFunctionTypeVariadic(cursorType) != 0,
+		obj := &ast.Object{
+			Kind: ast.Fun,
+			Name: "C." + name,
+		}
+		args := make([]*ast.Field, numArgs)
+		decl := &ast.FuncDecl{
+			Doc: &ast.CommentGroup{
+				List: []*ast.Comment{
+					{
+						Slash: pos - 1,
+						Text:  "//export " + name,
+					},
+				},
+			},
+			Name: &ast.Ident{
+				NamePos: pos,
+				Name:    "C." + name,
+				Obj:     obj,
+			},
+			Type: &ast.FuncType{
+				Func: pos,
+				Params: &ast.FieldList{
+					Opening: pos,
+					List:    args,
+					Closing: pos,
+				},
+			},
+		}
+		if C.clang_isFunctionTypeVariadic(cursorType) != 0 {
+			decl.Doc.List = append(decl.Doc.List, &ast.Comment{
+				Slash: pos - 1,
+				Text:  "//go:variadic",
+			})
 		}
-		p.functions[name] = fn
 		for i := 0; i < numArgs; i++ {
 			arg := C.tinygo_clang_Cursor_getArgument(c, C.uint(i))
 			argName := getString(C.tinygo_clang_getCursorSpelling(arg))
@@ -194,50 +224,108 @@ func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClient
 			if argName == "" {
 				argName = "$" + strconv.Itoa(i)
 			}
-			fn.args = append(fn.args, paramInfo{
-				name:     argName,
-				typeExpr: p.makeASTType(argType, pos),
-			})
+			args[i] = &ast.Field{
+				Names: []*ast.Ident{
+					{
+						NamePos: pos,
+						Name:    argName,
+						Obj: &ast.Object{
+							Kind: ast.Var,
+							Name: argName,
+							Decl: decl,
+						},
+					},
+				},
+				Type: f.makeDecayingASTType(argType, pos),
+			}
 		}
 		resultType := C.tinygo_clang_getCursorResultType(c)
 		if resultType.kind != C.CXType_Void {
-			fn.results = &ast.FieldList{
+			decl.Type.Results = &ast.FieldList{
 				List: []*ast.Field{
-					&ast.Field{
-						Type: p.makeASTType(resultType, pos),
+					{
+						Type: f.makeASTType(resultType, pos),
 					},
 				},
 			}
 		}
-	case C.CXCursor_StructDecl:
-		typ := C.tinygo_clang_getCursorType(c)
-		name := getString(C.tinygo_clang_getCursorSpelling(c))
-		if _, required := p.missingSymbols["struct_"+name]; !required {
-			return C.CXChildVisit_Continue
+		obj.Decl = decl
+		return decl, nil
+	case C.CXCursor_StructDecl, C.CXCursor_UnionDecl:
+		typ := f.makeASTRecordType(c, pos)
+		typeName := "C." + name
+		typeExpr := typ.typeExpr
+		if typ.unionSize != 0 {
+			// Convert to a single-field struct type.
+			typeExpr = f.makeUnionField(typ)
 		}
-		p.makeASTType(typ, pos)
+		obj := &ast.Object{
+			Kind: ast.Typ,
+			Name: typeName,
+		}
+		typeSpec := &ast.TypeSpec{
+			Name: &ast.Ident{
+				NamePos: typ.pos,
+				Name:    typeName,
+				Obj:     obj,
+			},
+			Type: typeExpr,
+		}
+		obj.Decl = typeSpec
+		return typeSpec, typ
 	case C.CXCursor_TypedefDecl:
-		typedefType := C.tinygo_clang_getCursorType(c)
-		name := getString(C.clang_getTypedefName(typedefType))
-		if _, required := p.missingSymbols[name]; !required {
-			return C.CXChildVisit_Continue
+		typeName := "C." + name
+		underlyingType := C.tinygo_clang_getTypedefDeclUnderlyingType(c)
+		obj := &ast.Object{
+			Kind: ast.Typ,
+			Name: typeName,
 		}
-		p.makeASTType(typedefType, pos)
+		typeSpec := &ast.TypeSpec{
+			Name: &ast.Ident{
+				NamePos: pos,
+				Name:    typeName,
+				Obj:     obj,
+			},
+			Type: f.makeASTType(underlyingType, pos),
+		}
+		if underlyingType.kind != C.CXType_Enum {
+			typeSpec.Assign = pos
+		}
+		obj.Decl = typeSpec
+		return typeSpec, nil
 	case C.CXCursor_VarDecl:
-		name := getString(C.tinygo_clang_getCursorSpelling(c))
-		if _, required := p.missingSymbols[name]; !required {
-			return C.CXChildVisit_Continue
-		}
 		cursorType := C.tinygo_clang_getCursorType(c)
-		p.globals[name] = globalInfo{
-			typeExpr: p.makeASTType(cursorType, pos),
-			pos:      pos,
+		typeExpr := f.makeASTType(cursorType, pos)
+		gen := &ast.GenDecl{
+			TokPos: pos,
+			Tok:    token.VAR,
+			Lparen: token.NoPos,
+			Rparen: token.NoPos,
+			Doc: &ast.CommentGroup{
+				List: []*ast.Comment{
+					{
+						Slash: pos - 1,
+						Text:  "//go:extern " + name,
+					},
+				},
+			},
 		}
+		obj := &ast.Object{
+			Kind: ast.Var,
+			Name: "C." + name,
+		}
+		valueSpec := &ast.ValueSpec{
+			Names: []*ast.Ident{{
+				NamePos: pos,
+				Name:    "C." + name,
+				Obj:     obj,
+			}},
+			Type: typeExpr,
+		}
+		obj.Decl = valueSpec
+		gen.Specs = append(gen.Specs, valueSpec)
+		return gen, nil
 	case C.CXCursor_MacroDefinition:
-		name := getString(C.tinygo_clang_getCursorSpelling(c))
-		if _, required := p.missingSymbols[name]; !required {
-			return C.CXChildVisit_Continue
-		}
 		sourceRange := C.tinygo_clang_getCursorExtent(c)
 		start := C.clang_getRangeStart(sourceRange)
 		end := C.clang_getRangeEnd(sourceRange)
@@ -245,17 +333,17 @@ func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClient
 		var startOffset, endOffset C.unsigned
 		C.clang_getExpansionLocation(start, &file, nil, nil, &startOffset)
 		if file == nil {
-			p.addError(pos, "internal error: could not find file where macro is defined")
-			break
+			f.addError(pos, "internal error: could not find file where macro is defined")
+			return nil, nil
 		}
 		C.clang_getExpansionLocation(end, &endFile, nil, nil, &endOffset)
 		if file != endFile {
-			p.addError(pos, "internal error: expected start and end location of a macro to be in the same file")
-			break
+			f.addError(pos, "internal error: expected start and end location of a macro to be in the same file")
+			return nil, nil
 		}
 		if startOffset > endOffset {
-			p.addError(pos, "internal error: start offset of macro is after end offset")
-			break
+			f.addError(pos, "internal error: start offset of macro is after end offset")
+			return nil, nil
 		}
 
 		// read file contents and extract the relevant byte range
@@ -263,31 +351,94 @@ func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClient
 		var size C.size_t
 		sourcePtr := C.clang_getFileContents(tu, file, &size)
 		if endOffset >= C.uint(size) {
-			p.addError(pos, "internal error: end offset of macro lies after end of file")
-			break
+			f.addError(pos, "internal error: end offset of macro lies after end of file")
+			return nil, nil
 		}
 		source := string(((*[1 << 28]byte)(unsafe.Pointer(sourcePtr)))[startOffset:endOffset:endOffset])
 		if !strings.HasPrefix(source, name) {
-			p.addError(pos, fmt.Sprintf("internal error: expected macro value to start with %#v, got %#v", name, source))
-			break
+			f.addError(pos, fmt.Sprintf("internal error: expected macro value to start with %#v, got %#v", name, source))
+			return nil, nil
 		}
 		value := source[len(name):]
 		// Try to convert this #define into a Go constant expression.
-		expr, scannerError := parseConst(pos+token.Pos(len(name)), p.fset, value)
+		expr, scannerError := parseConst(pos+token.Pos(len(name)), f.fset, value)
 		if scannerError != nil {
-			p.errors = append(p.errors, *scannerError)
+			f.errors = append(f.errors, *scannerError)
+			return nil, nil
 		}
-		if expr != nil {
-			// Parsing was successful.
-			p.constants[name] = constantInfo{expr, pos}
+
+		gen := &ast.GenDecl{
+			TokPos: token.NoPos,
+			Tok:    token.CONST,
+			Lparen: token.NoPos,
+			Rparen: token.NoPos,
 		}
+		obj := &ast.Object{
+			Kind: ast.Con,
+			Name: "C." + name,
+		}
+		valueSpec := &ast.ValueSpec{
+			Names: []*ast.Ident{{
+				NamePos: pos,
+				Name:    "C." + name,
+				Obj:     obj,
+			}},
+			Values: []ast.Expr{expr},
+		}
+		obj.Decl = valueSpec
+		gen.Specs = append(gen.Specs, valueSpec)
+		return gen, nil
 	case C.CXCursor_EnumDecl:
-		// Visit all enums, because the fields may be used even when the enum
-		// type itself is not.
-		typ := C.tinygo_clang_getCursorType(c)
-		p.makeASTType(typ, pos)
+		obj := &ast.Object{
+			Kind: ast.Typ,
+			Name: "C." + name,
+		}
+		underlying := C.tinygo_clang_getEnumDeclIntegerType(c)
+		// TODO: gc's CGo implementation uses types such as `uint32` for enums
+		// instead of types such as C.int, which are used here.
+		typeSpec := &ast.TypeSpec{
+			Name: &ast.Ident{
+				NamePos: pos,
+				Name:    "C." + name,
+				Obj:     obj,
+			},
+			Assign: pos,
+			Type:   f.makeASTType(underlying, pos),
+		}
+		obj.Decl = typeSpec
+		return typeSpec, nil
+	case C.CXCursor_EnumConstantDecl:
+		value := C.tinygo_clang_getEnumConstantDeclValue(c)
+		expr := &ast.BasicLit{
+			ValuePos: pos,
+			Kind:     token.INT,
+			Value:    strconv.FormatInt(int64(value), 10),
+		}
+		gen := &ast.GenDecl{
+			TokPos: token.NoPos,
+			Tok:    token.CONST,
+			Lparen: token.NoPos,
+			Rparen: token.NoPos,
+		}
+		obj := &ast.Object{
+			Kind: ast.Con,
+			Name: "C." + name,
+		}
+		valueSpec := &ast.ValueSpec{
+			Names: []*ast.Ident{{
+				NamePos: pos,
+				Name:    "C." + name,
+				Obj:     obj,
+			}},
+			Values: []ast.Expr{expr},
+		}
+		obj.Decl = valueSpec
+		gen.Specs = append(gen.Specs, valueSpec)
+		return gen, nil
+	default:
+		f.addError(pos, fmt.Sprintf("internal error: unknown cursor type: %d", kind))
+		return nil, nil
 	}
-	return C.CXChildVisit_Continue
 }
 
 func getString(clangString C.CXString) (s string) {
@@ -297,6 +448,49 @@ func getString(clangString C.CXString) (s string) {
 	return
 }
 
+//export tinygo_clang_globals_visitor
+func tinygo_clang_globals_visitor(c, parent C.GoCXCursor, client_data C.CXClientData) C.int {
+	f := storedRefs.Get(unsafe.Pointer(client_data)).(*cgoFile)
+	switch C.tinygo_clang_getCursorKind(c) {
+	case C.CXCursor_FunctionDecl:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		f.names[name] = c
+	case C.CXCursor_StructDecl:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		if name != "" {
+			f.names["struct_"+name] = c
+		}
+	case C.CXCursor_UnionDecl:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		if name != "" {
+			f.names["union_"+name] = c
+		}
+	case C.CXCursor_TypedefDecl:
+		typedefType := C.tinygo_clang_getCursorType(c)
+		name := getString(C.clang_getTypedefName(typedefType))
+		f.names[name] = c
+	case C.CXCursor_VarDecl:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		f.names[name] = c
+	case C.CXCursor_MacroDefinition:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		f.names[name] = c
+	case C.CXCursor_EnumDecl:
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		if name != "" {
+			// Named enum, which can be referenced from Go using C.enum_foo.
+			f.names["enum_"+name] = c
+		}
+		// The enum fields are in global scope, so recurse to visit them.
+		return C.CXChildVisit_Recurse
+	case C.CXCursor_EnumConstantDecl:
+		// We arrive here because of the "Recurse" above.
+		name := getString(C.tinygo_clang_getCursorSpelling(c))
+		f.names[name] = c
+	}
+	return C.CXChildVisit_Continue
+}
+
 // getCursorPosition returns a usable token.Pos from a libclang cursor.
 func (p *cgoPackage) getCursorPosition(cursor C.GoCXCursor) token.Pos {
 	return p.getClangLocationPosition(C.tinygo_clang_getCursorLocation(cursor), C.tinygo_clang_Cursor_getTranslationUnit(cursor))
@@ -380,7 +574,7 @@ func (p *cgoPackage) addErrorAfter(pos token.Pos, after, msg string) {
 func (p *cgoPackage) addErrorAt(position token.Position, msg string) {
 	if filepath.IsAbs(position.Filename) {
 		// Relative paths for readability, like other Go parser errors.
-		relpath, err := filepath.Rel(p.dir, position.Filename)
+		relpath, err := filepath.Rel(p.currentDir, position.Filename)
 		if err == nil {
 			position.Filename = relpath
 		}
@@ -391,9 +585,44 @@ func (p *cgoPackage) addErrorAt(position token.Position, msg string) {
 	})
 }
 
+// makeDecayingASTType does the same as makeASTType but takes care of decaying
+// types (arrays in function parameters, etc). It is otherwise identical to
+// makeASTType.
+func (f *cgoFile) makeDecayingASTType(typ C.CXType, pos token.Pos) ast.Expr {
+	// Strip typedefs, if any.
+	underlyingType := typ
+	if underlyingType.kind == C.CXType_Typedef {
+		c := C.tinygo_clang_getTypeDeclaration(typ)
+		underlyingType = C.tinygo_clang_getTypedefDeclUnderlyingType(c)
+		// TODO: support a chain of typedefs. At the moment, it seems to get
+		// stuck in an endless loop when trying to get to the most underlying
+		// type.
+	}
+	// Check for decaying type. An example would be an array type in a
+	// parameter. This declaration:
+	//   void foo(char buf[6]);
+	// is the same as this one:
+	//   void foo(char *buf);
+	// But this one:
+	//   void bar(char buf[6][4]);
+	// equals this:
+	//   void bar(char *buf[4]);
+	// so not all array dimensions should be stripped, just the first one.
+	// TODO: there are more kinds of decaying types.
+	if underlyingType.kind == C.CXType_ConstantArray {
+		// Apply type decaying.
+		pointeeType := C.clang_getElementType(underlyingType)
+		return &ast.StarExpr{
+			Star: pos,
+			X:    f.makeASTType(pointeeType, pos),
+		}
+	}
+	return f.makeASTType(typ, pos)
+}
+
 // makeASTType return the ast.Expr for the given libclang type. In other words,
 // it converts a libclang type to a type in the Go AST.
-func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
+func (f *cgoFile) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 	var typeName string
 	switch typ.kind {
 	case C.CXType_Char_S, C.CXType_Char_U:
@@ -454,7 +683,7 @@ func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 		}
 		return &ast.StarExpr{
 			Star: pos,
-			X:    p.makeASTType(pointeeType, pos),
+			X:    f.makeASTType(pointeeType, pos),
 		}
 	case C.CXType_ConstantArray:
 		return &ast.ArrayType{
@@ -464,7 +693,7 @@ func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 				Kind:     token.INT,
 				Value:    strconv.FormatInt(int64(C.clang_getArraySize(typ)), 10),
 			},
-			Elt: p.makeASTType(C.clang_getElementType(typ), pos),
+			Elt: f.makeASTType(C.clang_getElementType(typ), pos),
 		}
 	case C.CXType_FunctionProto:
 		// Be compatible with gc, which uses the *[0]byte type for function
@@ -485,71 +714,21 @@ func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 		}
 	case C.CXType_Typedef:
 		name := getString(C.clang_getTypedefName(typ))
-		if _, ok := p.typedefs[name]; !ok {
-			p.typedefs[name] = nil // don't recurse
-			c := C.tinygo_clang_getTypeDeclaration(typ)
-			underlyingType := C.tinygo_clang_getTypedefDeclUnderlyingType(c)
-			expr := p.makeASTType(underlyingType, pos)
-			if strings.HasPrefix(name, "_Cgo_") {
-				expr := expr.(*ast.Ident)
-				typeSize := C.clang_Type_getSizeOf(underlyingType)
-				switch expr.Name {
-				case "C.char":
-					if typeSize != 1 {
-						// This happens for some very special purpose architectures
-						// (DSPs etc.) that are not currently targeted.
-						// https://www.embecosm.com/2017/04/18/non-8-bit-char-support-in-clang-and-llvm/
-						p.addError(pos, fmt.Sprintf("unknown char width: %d", typeSize))
-					}
-					switch underlyingType.kind {
-					case C.CXType_Char_S:
-						expr.Name = "int8"
-					case C.CXType_Char_U:
-						expr.Name = "uint8"
-					}
-				case "C.schar", "C.short", "C.int", "C.long", "C.longlong":
-					switch typeSize {
-					case 1:
-						expr.Name = "int8"
-					case 2:
-						expr.Name = "int16"
-					case 4:
-						expr.Name = "int32"
-					case 8:
-						expr.Name = "int64"
-					}
-				case "C.uchar", "C.ushort", "C.uint", "C.ulong", "C.ulonglong":
-					switch typeSize {
-					case 1:
-						expr.Name = "uint8"
-					case 2:
-						expr.Name = "uint16"
-					case 4:
-						expr.Name = "uint32"
-					case 8:
-						expr.Name = "uint64"
-					}
-				}
-			}
-			p.typedefs[name] = &typedefInfo{
-				typeExpr: expr,
-				pos:      pos,
-			}
-		}
+		c := C.tinygo_clang_getTypeDeclaration(typ)
 		return &ast.Ident{
 			NamePos: pos,
-			Name:    "C." + name,
+			Name:    f.getASTDeclName(name, c, false),
 		}
 	case C.CXType_Elaborated:
 		underlying := C.clang_Type_getNamedType(typ)
 		switch underlying.kind {
 		case C.CXType_Record:
-			return p.makeASTType(underlying, pos)
+			return f.makeASTType(underlying, pos)
 		case C.CXType_Enum:
-			return p.makeASTType(underlying, pos)
+			return f.makeASTType(underlying, pos)
 		default:
 			typeKindSpelling := getString(C.clang_getTypeKindSpelling(underlying.kind))
-			p.addError(pos, fmt.Sprintf("unknown elaborated type (libclang type kind %s)", typeKindSpelling))
+			f.addError(pos, fmt.Sprintf("unknown elaborated type (libclang type kind %s)", typeKindSpelling))
 			typeName = "<unknown>"
 		}
 	case C.CXType_Record:
@@ -567,63 +746,46 @@ func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 		}
 		if name == "" {
 			// Anonymous record, probably inside a typedef.
-			typeInfo := p.makeASTRecordType(cursor, pos)
-			if typeInfo.bitfields != nil || typeInfo.unionSize != 0 {
-				// This record is a union or is a struct with bitfields, so we
-				// have to declare it as a named type (for getters/setters to
-				// work).
-				p.anonStructNum++
-				cgoName := cgoRecordPrefix + strconv.Itoa(p.anonStructNum)
-				p.elaboratedTypes[cgoName] = typeInfo
-				return &ast.Ident{
-					NamePos: pos,
-					Name:    "C." + cgoName,
-				}
+			clangLocation := C.tinygo_clang_getCursorLocation(cursor)
+			var file C.CXFile
+			var line C.unsigned
+			var column C.unsigned
+			C.clang_getFileLocation(clangLocation, &file, &line, &column, nil)
+			location := token.Position{
+				Filename: getString(C.clang_getFileName(file)),
+				Line:     int(line),
+				Column:   int(column),
 			}
-			return typeInfo.typeExpr
+			if location.Filename == "" || location.Line == 0 {
+				// Not sure when this would happen, but protect from it anyway.
+				f.addError(pos, "could not find file/line information")
+			}
+			name = f.getUnnamedDeclName("_Ctype_"+cgoRecordPrefix+"__", location)
 		} else {
-			cgoName := cgoRecordPrefix + name
-			if _, ok := p.elaboratedTypes[cgoName]; !ok {
-				p.elaboratedTypes[cgoName] = nil // predeclare (to avoid endless recursion)
-				p.elaboratedTypes[cgoName] = p.makeASTRecordType(cursor, pos)
-			}
-			return &ast.Ident{
-				NamePos: pos,
-				Name:    "C." + cgoName,
-			}
+			name = cgoRecordPrefix + name
+		}
+		return &ast.Ident{
+			NamePos: pos,
+			Name:    f.getASTDeclName(name, cursor, false),
 		}
 	case C.CXType_Enum:
 		cursor := C.tinygo_clang_getTypeDeclaration(typ)
 		name := getString(C.tinygo_clang_getCursorSpelling(cursor))
-		underlying := C.tinygo_clang_getEnumDeclIntegerType(cursor)
 		if name == "" {
-			// anonymous enum
-			ref := storedRefs.Put(p)
-			defer storedRefs.Remove(ref)
-			C.tinygo_clang_visitChildren(cursor, C.CXCursorVisitor(C.tinygo_clang_enum_visitor), C.CXClientData(ref))
-			return p.makeASTType(underlying, pos)
+			name = f.getUnnamedDeclName("_Ctype_enum___", cursor)
 		} else {
-			// named enum
-			if _, ok := p.enums[name]; !ok {
-				ref := storedRefs.Put(p)
-				defer storedRefs.Remove(ref)
-				C.tinygo_clang_visitChildren(cursor, C.CXCursorVisitor(C.tinygo_clang_enum_visitor), C.CXClientData(ref))
-				p.enums[name] = enumInfo{
-					typeExpr: p.makeASTType(underlying, pos),
-					pos:      pos,
-				}
-			}
-			return &ast.Ident{
-				NamePos: pos,
-				Name:    "C.enum_" + name,
-			}
+			name = "enum_" + name
+		}
+		return &ast.Ident{
+			NamePos: pos,
+			Name:    f.getASTDeclName(name, cursor, false),
 		}
 	}
 	if typeName == "" {
 		// Report this as an error.
 		typeSpelling := getString(C.clang_getTypeSpelling(typ))
 		typeKindSpelling := getString(C.clang_getTypeKindSpelling(typ.kind))
-		p.addError(pos, fmt.Sprintf("unknown C type: %v (libclang type kind %s)", typeSpelling, typeKindSpelling))
+		f.addError(pos, fmt.Sprintf("unknown C type: %v (libclang type kind %s)", typeSpelling, typeKindSpelling))
 		typeName = "C.<unknown>"
 	}
 	return &ast.Ident{
@@ -632,9 +794,80 @@ func (p *cgoPackage) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 	}
 }
 
+// getIntegerType returns an AST node that defines types such as C.int.
+func (p *cgoPackage) getIntegerType(name string, cursor clangCursor) *ast.TypeSpec {
+	pos := p.getCursorPosition(cursor)
+
+	// Find a Go type that matches the size and signedness of the given C type.
+	underlyingType := C.tinygo_clang_getTypedefDeclUnderlyingType(cursor)
+	var goName string
+	typeSize := C.clang_Type_getSizeOf(underlyingType)
+	switch name {
+	case "C.char":
+		if typeSize != 1 {
+			// This happens for some very special purpose architectures
+			// (DSPs etc.) that are not currently targeted.
+			// https://www.embecosm.com/2017/04/18/non-8-bit-char-support-in-clang-and-llvm/
+			p.addError(pos, fmt.Sprintf("unknown char width: %d", typeSize))
+		}
+		switch underlyingType.kind {
+		case C.CXType_Char_S:
+			goName = "int8"
+		case C.CXType_Char_U:
+			goName = "uint8"
+		}
+	case "C.schar", "C.short", "C.int", "C.long", "C.longlong":
+		switch typeSize {
+		case 1:
+			goName = "int8"
+		case 2:
+			goName = "int16"
+		case 4:
+			goName = "int32"
+		case 8:
+			goName = "int64"
+		}
+	case "C.uchar", "C.ushort", "C.uint", "C.ulong", "C.ulonglong":
+		switch typeSize {
+		case 1:
+			goName = "uint8"
+		case 2:
+			goName = "uint16"
+		case 4:
+			goName = "uint32"
+		case 8:
+			goName = "uint64"
+		}
+	}
+
+	if goName == "" { // should not happen
+		p.addError(pos, "internal error: did not find Go type for C type "+name)
+		goName = "int"
+	}
+
+	// Construct an *ast.TypeSpec for this type.
+	obj := &ast.Object{
+		Kind: ast.Typ,
+		Name: name,
+	}
+	spec := &ast.TypeSpec{
+		Name: &ast.Ident{
+			NamePos: pos,
+			Name:    name,
+			Obj:     obj,
+		},
+		Type: &ast.Ident{
+			NamePos: pos,
+			Name:    goName,
+		},
+	}
+	obj.Decl = spec
+	return spec
+}
+
 // makeASTRecordType parses a C record (struct or union) and translates it into
 // a Go struct type.
-func (p *cgoPackage) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elaboratedTypeInfo {
+func (f *cgoFile) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elaboratedTypeInfo {
 	fieldList := &ast.FieldList{
 		Opening: pos,
 		Closing: pos,
@@ -644,11 +877,11 @@ func (p *cgoPackage) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elab
 	bitfieldNum := 0
 	ref := storedRefs.Put(struct {
 		fieldList    *ast.FieldList
-		pkg          *cgoPackage
+		file         *cgoFile
 		inBitfield   *bool
 		bitfieldNum  *int
 		bitfieldList *[]bitfieldInfo
-	}{fieldList, p, &inBitfield, &bitfieldNum, &bitfieldList})
+	}{fieldList, f, &inBitfield, &bitfieldNum, &bitfieldList})
 	defer storedRefs.Remove(ref)
 	C.tinygo_clang_visitChildren(cursor, C.CXCursorVisitor(C.tinygo_clang_struct_visitor), C.CXClientData(ref))
 	renameFieldKeywords(fieldList)
@@ -677,13 +910,13 @@ func (p *cgoPackage) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elab
 		}
 		if bitfieldList != nil {
 			// This is valid C... but please don't do this.
-			p.addError(pos, "bitfield in a union is not supported")
+			f.addError(pos, "bitfield in a union is not supported")
 		}
 		typ := C.tinygo_clang_getCursorType(cursor)
 		alignInBytes := int64(C.clang_Type_getAlignOf(typ))
 		sizeInBytes := int64(C.clang_Type_getSizeOf(typ))
 		if sizeInBytes == 0 {
-			p.addError(pos, "zero-length union is not supported")
+			f.addError(pos, "zero-length union is not supported")
 		}
 		typeInfo.unionSize = sizeInBytes
 		typeInfo.unionAlign = alignInBytes
@@ -691,7 +924,7 @@ func (p *cgoPackage) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elab
 	default:
 		cursorKind := C.tinygo_clang_getCursorKind(cursor)
 		cursorKindSpelling := getString(C.clang_getCursorKindSpelling(cursorKind))
-		p.addError(pos, fmt.Sprintf("expected StructDecl or UnionDecl, not %s", cursorKindSpelling))
+		f.addError(pos, fmt.Sprintf("expected StructDecl or UnionDecl, not %s", cursorKindSpelling))
 		return &elaboratedTypeInfo{
 			typeExpr: &ast.StructType{
 				Struct: pos,
@@ -705,17 +938,17 @@ func (p *cgoPackage) makeASTRecordType(cursor C.GoCXCursor, pos token.Pos) *elab
 func tinygo_clang_struct_visitor(c, parent C.GoCXCursor, client_data C.CXClientData) C.int {
 	passed := storedRefs.Get(unsafe.Pointer(client_data)).(struct {
 		fieldList    *ast.FieldList
-		pkg          *cgoPackage
+		file         *cgoFile
 		inBitfield   *bool
 		bitfieldNum  *int
 		bitfieldList *[]bitfieldInfo
 	})
 	fieldList := passed.fieldList
-	p := passed.pkg
+	f := passed.file
 	inBitfield := passed.inBitfield
 	bitfieldNum := passed.bitfieldNum
 	bitfieldList := passed.bitfieldList
-	pos := p.getCursorPosition(c)
+	pos := f.getCursorPosition(c)
 	switch cursorKind := C.tinygo_clang_getCursorKind(c); cursorKind {
 	case C.CXCursor_FieldDecl:
 		// Expected. This is a regular field.
@@ -724,7 +957,7 @@ func tinygo_clang_struct_visitor(c, parent C.GoCXCursor, client_data C.CXClientD
 		return C.CXChildVisit_Continue
 	default:
 		cursorKindSpelling := getString(C.clang_getCursorKindSpelling(cursorKind))
-		p.addError(pos, fmt.Sprintf("expected FieldDecl in struct or union, not %s", cursorKindSpelling))
+		f.addError(pos, fmt.Sprintf("expected FieldDecl in struct or union, not %s", cursorKindSpelling))
 		return C.CXChildVisit_Continue
 	}
 	name := getString(C.tinygo_clang_getCursorSpelling(c))
@@ -735,14 +968,14 @@ func tinygo_clang_struct_visitor(c, parent C.GoCXCursor, client_data C.CXClientD
 	}
 	typ := C.tinygo_clang_getCursorType(c)
 	field := &ast.Field{
-		Type: p.makeASTType(typ, p.getCursorPosition(c)),
+		Type: f.makeASTType(typ, f.getCursorPosition(c)),
 	}
 	offsetof := int64(C.clang_Type_getOffsetOf(C.tinygo_clang_getCursorType(parent), C.CString(name)))
 	alignOf := int64(C.clang_Type_getAlignOf(typ) * 8)
 	bitfieldOffset := offsetof % alignOf
 	if bitfieldOffset != 0 {
 		if C.tinygo_clang_Cursor_isBitField(c) != 1 {
-			p.addError(pos, "expected a bitfield")
+			f.addError(pos, "expected a bitfield")
 			return C.CXChildVisit_Continue
 		}
 		if !*inBitfield {
@@ -775,7 +1008,7 @@ func tinygo_clang_struct_visitor(c, parent C.GoCXCursor, client_data C.CXClientD
 	}
 	*inBitfield = false
 	field.Names = []*ast.Ident{
-		&ast.Ident{
+		{
 			NamePos: pos,
 			Name:    name,
 			Obj: &ast.Object{
@@ -789,19 +1022,6 @@ func tinygo_clang_struct_visitor(c, parent C.GoCXCursor, client_data C.CXClientD
 	return C.CXChildVisit_Continue
 }
 
-//export tinygo_clang_enum_visitor
-func tinygo_clang_enum_visitor(c, parent C.GoCXCursor, client_data C.CXClientData) C.int {
-	p := storedRefs.Get(unsafe.Pointer(client_data)).(*cgoPackage)
-	name := getString(C.tinygo_clang_getCursorSpelling(c))
-	pos := p.getCursorPosition(c)
-	value := C.tinygo_clang_getEnumConstantDeclValue(c)
-	p.constants[name] = constantInfo{
-		expr: &ast.BasicLit{pos, token.INT, strconv.FormatInt(int64(value), 10)},
-		pos:  pos,
-	}
-	return C.CXChildVisit_Continue
-}
-
 //export tinygo_clang_inclusion_visitor
 func tinygo_clang_inclusion_visitor(includedFile C.CXFile, inclusionStack *C.CXSourceLocation, includeLen C.unsigned, clientData C.CXClientData) {
 	callback := storedRefs.Get(unsafe.Pointer(clientData)).(func(C.CXFile))

cgo/libclang_config.go

@@ -1,14 +0,0 @@
-// +build !byollvm
-// +build !llvm10
-
-package cgo
-
-/*
-#cgo linux   CFLAGS:  -I/usr/lib/llvm-11/include
-#cgo darwin  CFLAGS:  -I/usr/local/opt/llvm@11/include
-#cgo freebsd CFLAGS:  -I/usr/local/llvm11/include
-#cgo linux   LDFLAGS: -L/usr/lib/llvm-11/lib -lclang
-#cgo darwin  LDFLAGS: -L/usr/local/opt/llvm@11/lib -lclang -lffi
-#cgo freebsd LDFLAGS: -L/usr/local/llvm11/lib -lclang
-*/
-import "C"

cgo/libclang_config_llvm10.go

@@ -1,14 +0,0 @@
-// +build !byollvm
-// +build llvm10
-
-package cgo
-
-/*
-#cgo linux  CFLAGS: -I/usr/lib/llvm-10/include
-#cgo darwin CFLAGS: -I/usr/local/opt/llvm@10/include
-#cgo freebsd CFLAGS: -I/usr/local/llvm10/include
-#cgo linux  LDFLAGS: -L/usr/lib/llvm-10/lib -lclang
-#cgo darwin LDFLAGS: -L/usr/local/opt/llvm@10/lib -lclang -lffi
-#cgo freebsd LDFLAGS: -L/usr/local/llvm10/lib -lclang
-*/
-import "C"

cgo/libclang_config_llvm13.go

@@ -0,0 +1,16 @@
+//go:build !byollvm && !llvm14
+// +build !byollvm,!llvm14
+
+package cgo
+
+/*
+#cgo linux        CFLAGS:  -I/usr/lib/llvm-13/include
+#cgo darwin,amd64 CFLAGS:  -I/usr/local/opt/llvm@13/include
+#cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@13/include
+#cgo freebsd      CFLAGS:  -I/usr/local/llvm13/include
+#cgo linux        LDFLAGS: -L/usr/lib/llvm-13/lib -lclang
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@13/lib -lclang -lffi
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@13/lib -lclang -lffi
+#cgo freebsd      LDFLAGS: -L/usr/local/llvm13/lib -lclang
+*/
+import "C"

cgo/libclang_config_llvm14.go

@@ -0,0 +1,16 @@
+//go:build !byollvm && llvm14
+// +build !byollvm,llvm14
+
+package cgo
+
+/*
+#cgo linux        CFLAGS:  -I/usr/lib/llvm-14/include
+#cgo darwin,amd64 CFLAGS:  -I/usr/local/opt/llvm@14/include
+#cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@14/include
+#cgo freebsd      CFLAGS:  -I/usr/local/llvm14/include
+#cgo linux        LDFLAGS: -L/usr/lib/llvm-14/lib -lclang
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@14/lib -lclang -lffi
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@14/lib -lclang -lffi
+#cgo freebsd      LDFLAGS: -L/usr/local/llvm14/lib -lclang
+*/
+import "C"

cgo/libclang_stubs.c

@@ -3,7 +3,7 @@
 // are slightly different from the ones defined in libclang.go, but they
 // should be ABI compatible.
 
-#include <clang-c/Index.h> // if this fails, install libclang-10-dev
+#include <clang-c/Index.h> // If this fails, libclang headers aren't available. Please take a look here: https://tinygo.org/docs/guides/build/
 
 CXCursor tinygo_clang_getTranslationUnitCursor(CXTranslationUnit tu) {
 	return clang_getTranslationUnitCursor(tu);

cgo/testdata/basic.out.go

@@ -4,23 +4,36 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
-type C.int16_t = int16
-type C.int32_t = int32
-type C.int64_t = int64
-type C.int8_t = int8
-type C.uint16_t = uint16
-type C.uint32_t = uint32
-type C.uint64_t = uint64
-type C.uint8_t = uint8
-type C.uintptr_t = uintptr
-type C.char uint8
-type C.int int32
-type C.long int32
-type C.longlong int64
-type C.schar int8
-type C.short int16
-type C.uchar uint8
-type C.uint uint32
-type C.ulong uint32
-type C.ulonglong uint64
-type C.ushort uint16
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
+
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
+
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)

cgo/testdata/const.out.go

@@ -4,26 +4,39 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
-const C.bar = C.foo
-const C.foo = 3
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
 
-type C.int16_t = int16
-type C.int32_t = int32
-type C.int64_t = int64
-type C.int8_t = int8
-type C.uint16_t = uint16
-type C.uint32_t = uint32
-type C.uint64_t = uint64
-type C.uint8_t = uint8
-type C.uintptr_t = uintptr
-type C.char uint8
-type C.int int32
-type C.long int32
-type C.longlong int64
-type C.schar int8
-type C.short int16
-type C.uchar uint8
-type C.uint uint32
-type C.ulong uint32
-type C.ulonglong uint64
-type C.ushort uint16
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
+
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)
+
+const C.foo = 3
+const C.bar = C.foo

cgo/testdata/errors.go

@@ -14,6 +14,12 @@ typedef someType noType; // undefined type
 #define SOME_CONST_2 6) // const not used (so no error)
 #define SOME_CONST_3 1234 // const too large for byte
 */
+//
+//
+// #define SOME_CONST_4 8) // after some empty lines
+import "C"
+
+// #warning another warning
 import "C"
 
 // Make sure that errors for the following lines won't change with future
@@ -21,7 +27,7 @@ import "C"
 //line errors.go:100
 var (
 	// constant too large
-	_ C.uint8_t = 2 << 10
+	_ C.char = 2 << 10
 
 	// z member does not exist
 	_ C.point_t = C.point_t{z: 3}
@@ -30,4 +36,6 @@ var (
 	_ = C.SOME_CONST_1
 
 	_ byte = C.SOME_CONST_3
+
+	_ = C.SOME_CONST_4
 )

cgo/testdata/errors.out.go

@@ -1,13 +1,16 @@
 // CGo errors:
 //     testdata/errors.go:4:2: warning: some warning
 //     testdata/errors.go:11:9: error: unknown type name 'someType'
-//     testdata/errors.go:13:23: unexpected token )
+//     testdata/errors.go:22:5: warning: another warning
+//     testdata/errors.go:13:23: unexpected token ), expected end of expression
+//     testdata/errors.go:19:26: unexpected token ), expected end of expression
 
 // Type checking errors after CGo processing:
-//     testdata/errors.go:102: cannot use 2 << 10 (untyped int constant 2048) as uint8 value in variable declaration (overflows)
+//     testdata/errors.go:102: cannot use 2 << 10 (untyped int constant 2048) as C.char value in variable declaration (overflows)
 //     testdata/errors.go:105: unknown field z in struct literal
 //     testdata/errors.go:108: undeclared name: C.SOME_CONST_1
 //     testdata/errors.go:110: cannot use C.SOME_CONST_3 (untyped int constant 1234) as byte value in variable declaration (overflows)
+//     testdata/errors.go:112: undeclared name: C.SOME_CONST_4
 
 package main
 
@@ -15,29 +18,43 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
-const C.SOME_CONST_3 = 1234
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
 
-type C.int16_t = int16
-type C.int32_t = int32
-type C.int64_t = int64
-type C.int8_t = int8
-type C.uint16_t = uint16
-type C.uint32_t = uint32
-type C.uint64_t = uint64
-type C.uint8_t = uint8
-type C.uintptr_t = uintptr
-type C.char uint8
-type C.int int32
-type C.long int32
-type C.longlong int64
-type C.schar int8
-type C.short int16
-type C.uchar uint8
-type C.uint uint32
-type C.ulong uint32
-type C.ulonglong uint64
-type C.ushort uint16
-type C.point_t = struct {
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
+
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)
+type C._Ctype_struct___0 struct {
 	x C.int
 	y C.int
 }
+type C.point_t = C._Ctype_struct___0
+
+const C.SOME_CONST_3 = 1234

cgo/testdata/flags.out.go

@@ -9,26 +9,39 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
+
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
+
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)
+
 const C.BAR = 3
 const C.FOO_H = 1
-
-type C.int16_t = int16
-type C.int32_t = int32
-type C.int64_t = int64
-type C.int8_t = int8
-type C.uint16_t = uint16
-type C.uint32_t = uint32
-type C.uint64_t = uint64
-type C.uint8_t = uint8
-type C.uintptr_t = uintptr
-type C.char uint8
-type C.int int32
-type C.long int32
-type C.longlong int64
-type C.schar int8
-type C.short int16
-type C.uchar uint8
-type C.uint uint32
-type C.ulong uint32
-type C.ulonglong uint64
-type C.ushort uint16

cgo/testdata/symbols.go

@@ -0,0 +1,23 @@
+package main
+
+/*
+// Function signatures.
+int foo(int a, int b);
+void variadic0();
+void variadic2(int x, int y, ...);
+
+// Global variable signatures.
+extern int someValue;
+*/
+import "C"
+
+// Test function signatures.
+func accessFunctions() {
+	C.foo(3, 4)
+	C.variadic0()
+	C.variadic2(3, 5)
+}
+
+func accessGlobals() {
+	_ = C.someValue
+}

cgo/testdata/symbols.out.go

@@ -0,0 +1,59 @@
+package main
+
+import "unsafe"
+
+var _ unsafe.Pointer
+
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
+
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
+
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)
+
+//export foo
+func C.foo(a C.int, b C.int) C.int
+
+var C.foo$funcaddr unsafe.Pointer
+
+//export variadic0
+//go:variadic
+func C.variadic0()
+
+var C.variadic0$funcaddr unsafe.Pointer
+
+//export variadic2
+//go:variadic
+func C.variadic2(x C.int, y C.int)
+
+var C.variadic2$funcaddr unsafe.Pointer
+
+//go:extern someValue
+var C.someValue C.int

cgo/testdata/types.go

@@ -104,13 +104,13 @@ typedef struct {
 	unsigned char e : 3;
 	// Note that C++ allows bitfields bigger than the underlying type.
 } bitfield_t;
-
-// Function signatures.
-void variadic0();
-void variadic2(int x, int y, ...);
 */
 import "C"
 
+// // Test that we can refer from this CGo fragment to the fragment above.
+// typedef myint myint2;
+import "C"
+
 var (
 	// Simple typedefs.
 	_ C.myint
@@ -167,9 +167,3 @@ func accessUnion() {
 	var _ *C.int = union2d.unionfield_i()
 	var _ *[2]float64 = union2d.unionfield_d()
 }
-
-// Test function signatures.
-func accessFunctions() {
-	C.variadic0()
-	C.variadic2(3, 5)
-}

cgo/testdata/types.out.go

@@ -4,147 +4,146 @@ import "unsafe"
 
 var _ unsafe.Pointer
 
-func C.variadic0() //go:variadic
-func C.variadic2(x C.int, y C.int) //go:variadic
-var C.variadic0$funcaddr unsafe.Pointer
-var C.variadic2$funcaddr unsafe.Pointer
+//go:linkname C.CString runtime.cgo_CString
+func C.CString(string) *C.char
 
-const C.option2A = 20
-const C.optionA = 0
-const C.optionB = 1
-const C.optionC = -5
-const C.optionD = -4
-const C.optionE = 10
-const C.optionF = 11
-const C.optionG = 12
-const C.unused1 = 5
+//go:linkname C.GoString runtime.cgo_GoString
+func C.GoString(*C.char) string
 
-type C.int16_t = int16
-type C.int32_t = int32
-type C.int64_t = int64
-type C.int8_t = int8
-type C.uint16_t = uint16
-type C.uint32_t = uint32
-type C.uint64_t = uint64
-type C.uint8_t = uint8
-type C.uintptr_t = uintptr
-type C.char uint8
-type C.int int32
-type C.long int32
-type C.longlong int64
-type C.schar int8
-type C.short int16
-type C.uchar uint8
-type C.uint uint32
-type C.ulong uint32
-type C.ulonglong uint64
-type C.ushort uint16
-type C.bitfield_t = C.struct_4
-type C.myIntArray = [10]C.int
+//go:linkname C.__GoStringN runtime.cgo_GoStringN
+func C.__GoStringN(*C.char, uintptr) string
+
+func C.GoStringN(cstr *C.char, length C.int) string {
+	return C.__GoStringN(cstr, uintptr(length))
+}
+
+//go:linkname C.__GoBytes runtime.cgo_GoBytes
+func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+
+func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
+	return C.__GoBytes(ptr, uintptr(length))
+}
+
+type (
+	C.char      uint8
+	C.schar     int8
+	C.uchar     uint8
+	C.short     int16
+	C.ushort    uint16
+	C.int       int32
+	C.uint      uint32
+	C.long      int32
+	C.ulong     uint32
+	C.longlong  int64
+	C.ulonglong uint64
+)
 type C.myint = C.int
-type C.option2_t = C.uint
-type C.option_t = C.enum_option
-type C.point2d_t = struct {
+type C._Ctype_struct___0 struct {
 	x C.int
 	y C.int
 }
-type C.point3d_t = C.struct_point3d
-type C.struct_nested_t = struct {
-	begin C.point2d_t
-	end   C.point2d_t
-	tag   C.int
-
-	coord C.union_2
-}
-type C.types_t = struct {
-	f   float32
-	d   float64
-	ptr *C.int
-}
-type C.union1_t = struct{ i C.int }
-type C.union2d_t = C.union_union2d
-type C.union3_t = C.union_1
-type C.union_nested_t = C.union_3
-type C.unionarray_t = struct{ arr [10]C.uchar }
-
-func (s *C.struct_4) bitfield_a() C.uchar {
-	return s.__bitfield_1 & 0x1f
-}
-func (s *C.struct_4) set_bitfield_a(value C.uchar) {
-	s.__bitfield_1 = s.__bitfield_1&^0x1f | value&0x1f<<0
-}
-func (s *C.struct_4) bitfield_b() C.uchar {
-	return s.__bitfield_1 >> 5 & 0x1
-}
-func (s *C.struct_4) set_bitfield_b(value C.uchar) {
-	s.__bitfield_1 = s.__bitfield_1&^0x20 | value&0x1<<5
-}
-func (s *C.struct_4) bitfield_c() C.uchar {
-	return s.__bitfield_1 >> 6
-}
-func (s *C.struct_4) set_bitfield_c(value C.uchar,
-
-) { s.__bitfield_1 = s.__bitfield_1&0x3f | value<<6 }
-
-type C.struct_4 struct {
-	start        C.uchar
-	__bitfield_1 C.uchar
-
-	d C.uchar
-	e C.uchar
-}
+type C.point2d_t = C._Ctype_struct___0
 type C.struct_point3d struct {
 	x C.int
 	y C.int
 	z C.int
 }
+type C.point3d_t = C.struct_point3d
 type C.struct_type1 struct {
 	_type   C.int
 	__type  C.int
 	___type C.int
 }
 type C.struct_type2 struct{ _type C.int }
+type C._Ctype_union___1 struct{ i C.int }
+type C.union1_t = C._Ctype_union___1
+type C._Ctype_union___2 struct{ $union uint64 }
 
-func (union *C.union_1) unionfield_i() *C.int {
+func (union *C._Ctype_union___2) unionfield_i() *C.int {
 	return (*C.int)(unsafe.Pointer(&union.$union))
 }
-func (union *C.union_1) unionfield_d() *float64 {
+func (union *C._Ctype_union___2) unionfield_d() *float64 {
 	return (*float64)(unsafe.Pointer(&union.$union))
 }
-func (union *C.union_1) unionfield_s() *C.short {
+func (union *C._Ctype_union___2) unionfield_s() *C.short {
 	return (*C.short)(unsafe.Pointer(&union.$union))
 }
 
-type C.union_1 struct{ $union uint64 }
+type C.union3_t = C._Ctype_union___2
+type C.union_union2d struct{ $union [2]uint64 }
 
-func (union *C.union_2) unionfield_area() *C.point2d_t {
-	return (*C.point2d_t)(unsafe.Pointer(&union.$union))
-}
-func (union *C.union_2) unionfield_solid() *C.point3d_t {
-	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
-}
-
-type C.union_2 struct{ $union [3]uint32 }
-
-func (union *C.union_3) unionfield_point() *C.point3d_t {
-	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
-}
-func (union *C.union_3) unionfield_array() *C.unionarray_t {
-	return (*C.unionarray_t)(unsafe.Pointer(&union.$union))
-}
-func (union *C.union_3) unionfield_thing() *C.union3_t {
-	return (*C.union3_t)(unsafe.Pointer(&union.$union))
-}
-
-type C.union_3 struct{ $union [2]uint64 }
-
-func (union *C.union_union2d) unionfield_i() *C.int {
-	return (*C.int)(unsafe.Pointer(&union.$union))
-}
+func (union *C.union_union2d) unionfield_i() *C.int { return (*C.int)(unsafe.Pointer(&union.$union)) }
 func (union *C.union_union2d) unionfield_d() *[2]float64 {
 	return (*[2]float64)(unsafe.Pointer(&union.$union))
 }
 
-type C.union_union2d struct{ $union [2]uint64 }
-type C.enum_option C.int
-type C.enum_unused C.uint
+type C.union2d_t = C.union_union2d
+type C._Ctype_union___3 struct{ arr [10]C.uchar }
+type C.unionarray_t = C._Ctype_union___3
+type C._Ctype_union___5 struct{ $union [3]uint32 }
+
+func (union *C._Ctype_union___5) unionfield_area() *C.point2d_t {
+	return (*C.point2d_t)(unsafe.Pointer(&union.$union))
+}
+func (union *C._Ctype_union___5) unionfield_solid() *C.point3d_t {
+	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
+}
+
+type C._Ctype_struct___4 struct {
+	begin C.point2d_t
+	end   C.point2d_t
+	tag   C.int
+
+	coord C._Ctype_union___5
+}
+type C.struct_nested_t = C._Ctype_struct___4
+type C._Ctype_union___6 struct{ $union [2]uint64 }
+
+func (union *C._Ctype_union___6) unionfield_point() *C.point3d_t {
+	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
+}
+func (union *C._Ctype_union___6) unionfield_array() *C.unionarray_t {
+	return (*C.unionarray_t)(unsafe.Pointer(&union.$union))
+}
+func (union *C._Ctype_union___6) unionfield_thing() *C.union3_t {
+	return (*C.union3_t)(unsafe.Pointer(&union.$union))
+}
+
+type C.union_nested_t = C._Ctype_union___6
+type C.enum_option = C.int
+type C.option_t = C.enum_option
+type C._Ctype_enum___7 = C.uint
+type C.option2_t = C._Ctype_enum___7
+type C._Ctype_struct___8 struct {
+	f   float32
+	d   float64
+	ptr *C.int
+}
+type C.types_t = C._Ctype_struct___8
+type C.myIntArray = [10]C.int
+type C._Ctype_struct___9 struct {
+	start        C.uchar
+	__bitfield_1 C.uchar
+
+	d C.uchar
+	e C.uchar
+}
+
+func (s *C._Ctype_struct___9) bitfield_a() C.uchar { return s.__bitfield_1 & 0x1f }
+func (s *C._Ctype_struct___9) set_bitfield_a(value C.uchar) {
+	s.__bitfield_1 = s.__bitfield_1&^0x1f | value&0x1f<<0
+}
+func (s *C._Ctype_struct___9) bitfield_b() C.uchar {
+	return s.__bitfield_1 >> 5 & 0x1
+}
+func (s *C._Ctype_struct___9) set_bitfield_b(value C.uchar) {
+	s.__bitfield_1 = s.__bitfield_1&^0x20 | value&0x1<<5
+}
+func (s *C._Ctype_struct___9) bitfield_c() C.uchar {
+	return s.__bitfield_1 >> 6
+}
+func (s *C._Ctype_struct___9) set_bitfield_c(value C.uchar,
+
+) { s.__bitfield_1 = s.__bitfield_1&0x3f | value<<6 }
+
+type C.bitfield_t = C._Ctype_struct___9

compileopts/config.go

@@ -5,10 +5,12 @@ package compileopts
 import (
 	"errors"
 	"fmt"
+	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
 
+	"github.com/google/shlex"
 	"github.com/tinygo-org/tinygo/goenv"
 )
 
@@ -21,7 +23,7 @@ type Config struct {
 	TestConfig     TestConfig
 }
 
-// Triple returns the LLVM target triple, like armv6m-none-eabi.
+// Triple returns the LLVM target triple, like armv6m-unknown-unknown-eabi.
 func (c *Config) Triple() string {
 	return c.Target.Triple
 }
@@ -33,10 +35,16 @@ func (c *Config) CPU() string {
 }
 
 // Features returns a list of features this CPU supports. For example, for a
-// RISC-V processor, that could be ["+a", "+c", "+m"]. For many targets, an
-// empty list will be returned.
-func (c *Config) Features() []string {
-	return c.Target.Features
+// RISC-V processor, that could be "+a,+c,+m". For many targets, an empty list
+// will be returned.
+func (c *Config) Features() string {
+	if c.Target.Features == "" {
+		return c.Options.LLVMFeatures
+	}
+	if c.Options.LLVMFeatures == "" {
+		return c.Target.Features
+	}
+	return c.Target.Features + "," + c.Options.LLVMFeatures
 }
 
 // GOOS returns the GOOS of the target. This might not always be the actual OS:
@@ -53,9 +61,15 @@ func (c *Config) GOARCH() string {
 	return c.Target.GOARCH
 }
 
+// GOARM will return the GOARM environment variable given to the compiler when
+// building a program.
+func (c *Config) GOARM() string {
+	return c.Options.GOARM
+}
+
 // BuildTags returns the complete list of build tags used during this build.
 func (c *Config) BuildTags() []string {
-	tags := append(c.Target.BuildTags, []string{"tinygo", "gc." + c.GC(), "scheduler." + c.Scheduler()}...)
+	tags := append(c.Target.BuildTags, []string{"tinygo", "math_big_pure_go", "gc." + c.GC(), "scheduler." + c.Scheduler(), "serial." + c.Serial()}...)
 	for i := 1; i <= c.GoMinorVersion; i++ {
 		tags = append(tags, fmt.Sprintf("go1.%d", i))
 	}
@@ -72,7 +86,7 @@ func (c *Config) CgoEnabled() bool {
 }
 
 // GC returns the garbage collection strategy in use on this platform. Valid
-// values are "none", "leaking", "extalloc", and "conservative".
+// values are "none", "leaking", and "conservative".
 func (c *Config) GC() string {
 	if c.Options.GC != "" {
 		return c.Options.GC
@@ -80,21 +94,16 @@ func (c *Config) GC() string {
 	if c.Target.GC != "" {
 		return c.Target.GC
 	}
-	for _, tag := range c.Target.BuildTags {
-		if tag == "baremetal" || tag == "wasm" {
-			return "conservative"
-		}
-	}
-	return "extalloc"
+	return "conservative"
 }
 
 // NeedsStackObjects returns true if the compiler should insert stack objects
 // that can be traced by the garbage collector.
 func (c *Config) NeedsStackObjects() bool {
 	switch c.GC() {
-	case "conservative", "extalloc":
+	case "conservative":
 		for _, tag := range c.BuildTags() {
-			if tag == "wasm" {
+			if tag == "tinygo.wasm" {
 				return true
 			}
 		}
@@ -106,7 +115,7 @@ func (c *Config) NeedsStackObjects() bool {
 }
 
 // Scheduler returns the scheduler implementation. Valid values are "none",
-//"coroutines" and "tasks".
+// "asyncify" and "tasks".
 func (c *Config) Scheduler() string {
 	if c.Options.Scheduler != "" {
 		return c.Options.Scheduler
@@ -114,32 +123,40 @@ func (c *Config) Scheduler() string {
 	if c.Target.Scheduler != "" {
 		return c.Target.Scheduler
 	}
-	// Fall back to coroutines, which are supported everywhere.
-	return "coroutines"
+	// Fall back to none.
+	return "none"
 }
 
-// FuncImplementation picks an appropriate func value implementation for the
-// target.
-func (c *Config) FuncImplementation() string {
-	switch c.Scheduler() {
-	case "tasks":
-		// A func value is implemented as a pair of pointers:
-		//     {context, function pointer}
-		// where the context may be a pointer to a heap-allocated struct
-		// containing the free variables, or it may be undef if the function
-		// being pointed to doesn't need a context. The function pointer is a
-		// regular function pointer.
-		return "doubleword"
-	case "none", "coroutines":
-		// As "doubleword", but with the function pointer replaced by a unique
-		// ID per function signature. Function values are called by using a
-		// switch statement and choosing which function to call.
-		// Pick the switch implementation with the coroutines scheduler, as it
-		// allows the use of blocking inside a function that is used as a func
-		// value.
-		return "switch"
+// Serial returns the serial implementation for this build configuration: uart,
+// usb (meaning USB-CDC), or none.
+func (c *Config) Serial() string {
+	if c.Options.Serial != "" {
+		return c.Options.Serial
+	}
+	if c.Target.Serial != "" {
+		return c.Target.Serial
+	}
+	return "none"
+}
+
+// OptLevels returns the optimization level (0-2), size level (0-2), and inliner
+// threshold as used in the LLVM optimization pipeline.
+func (c *Config) OptLevels() (optLevel, sizeLevel int, inlinerThreshold uint) {
+	switch c.Options.Opt {
+	case "none", "0":
+		return 0, 0, 0 // -O0
+	case "1":
+		return 1, 0, 0 // -O1
+	case "2":
+		return 2, 0, 225 // -O2
+	case "s":
+		return 2, 1, 225 // -Os
+	case "z":
+		return 2, 2, 5 // -Oz, default
 	default:
-		panic("unknown scheduler type")
+		// This is not shown to the user: valid choices are already checked as
+		// part of Options.Verify(). It is here as a sanity check.
+		panic("unknown optimization level: -opt=" + c.Options.Opt)
 	}
 }
 
@@ -160,20 +177,159 @@ func (c *Config) AutomaticStackSize() bool {
 	return false
 }
 
+// UseThinLTO returns whether ThinLTO should be used for the given target. Some
+// targets (such as wasm) are not yet supported.
+// We should try and remove as many exceptions as possible in the future, so
+// that this optimization can be applied in more places.
+func (c *Config) UseThinLTO() bool {
+	parts := strings.Split(c.Triple(), "-")
+	if parts[0] == "wasm32" {
+		// wasm-ld doesn't seem to support ThinLTO yet.
+		return false
+	}
+	if parts[0] == "avr" || parts[0] == "xtensa" {
+		// These use external (GNU) linkers which might perhaps support ThinLTO
+		// through a plugin, but it's too much hassle to set up.
+		return false
+	}
+	// Other architectures support ThinLTO.
+	return true
+}
+
+// RP2040BootPatch returns whether the RP2040 boot patch should be applied that
+// calculates and patches in the checksum for the 2nd stage bootloader.
+func (c *Config) RP2040BootPatch() bool {
+	if c.Target.RP2040BootPatch != nil {
+		return *c.Target.RP2040BootPatch
+	}
+	return false
+}
+
+// MuslArchitecture returns the architecture name as used in musl libc. It is
+// usually the same as the first part of the LLVM triple, but not always.
+func MuslArchitecture(triple string) string {
+	arch := strings.Split(triple, "-")[0]
+	if strings.HasPrefix(arch, "arm") || strings.HasPrefix(arch, "thumb") {
+		arch = "arm"
+	}
+	return arch
+}
+
+// LibcPath returns the path to the libc directory. The libc path will be either
+// a precompiled libc shipped with a TinyGo build, or a libc path in the cache
+// directory (which might not yet be built).
+func (c *Config) LibcPath(name string) (path string, precompiled bool) {
+	archname := c.Triple()
+	if c.CPU() != "" {
+		archname += "-" + c.CPU()
+	}
+
+	// Try to load a precompiled library.
+	precompiledDir := filepath.Join(goenv.Get("TINYGOROOT"), "pkg", archname, name)
+	if _, err := os.Stat(precompiledDir); err == nil {
+		// Found a precompiled library for this OS/architecture. Return the path
+		// directly.
+		return precompiledDir, true
+	}
+
+	// No precompiled library found. Determine the path name that will be used
+	// in the build cache.
+	return filepath.Join(goenv.Get("GOCACHE"), name+"-"+archname), false
+}
+
+// DefaultBinaryExtension returns the default extension for binaries, such as
+// .exe, .wasm, or no extension (depending on the target).
+func (c *Config) DefaultBinaryExtension() string {
+	parts := strings.Split(c.Triple(), "-")
+	if parts[0] == "wasm32" {
+		// WebAssembly files always have the .wasm file extension.
+		return ".wasm"
+	}
+	if len(parts) >= 3 && parts[2] == "windows" {
+		// Windows uses .exe.
+		return ".exe"
+	}
+	if len(parts) >= 3 && parts[2] == "unknown" {
+		// There appears to be a convention to use the .elf file extension for
+		// ELF files intended for microcontrollers. I'm not aware of the origin
+		// of this, it's just something that is used by many projects.
+		// I think it's a good tradition, so let's keep it.
+		return ".elf"
+	}
+	// Linux, MacOS, etc, don't use a file extension. Use it as a fallback.
+	return ""
+}
+
 // CFlags returns the flags to pass to the C compiler. This is necessary for CGo
 // preprocessing.
 func (c *Config) CFlags() []string {
-	cflags := append([]string{}, c.Options.CFlags...)
+	var cflags []string
 	for _, flag := range c.Target.CFlags {
 		cflags = append(cflags, strings.ReplaceAll(flag, "{root}", goenv.Get("TINYGOROOT")))
 	}
-	if c.Target.Libc == "picolibc" {
+	switch c.Target.Libc {
+	case "darwin-libSystem":
 		root := goenv.Get("TINYGOROOT")
-		cflags = append(cflags, "-nostdlibinc", "-Xclang", "-internal-isystem", "-Xclang", filepath.Join(root, "lib", "picolibc", "newlib", "libc", "include"))
-		cflags = append(cflags, "-I"+filepath.Join(root, "lib/picolibc-include"))
+		cflags = append(cflags,
+			"--sysroot="+filepath.Join(root, "lib/macos-minimal-sdk/src"),
+		)
+	case "picolibc":
+		root := goenv.Get("TINYGOROOT")
+		picolibcDir := filepath.Join(root, "lib", "picolibc", "newlib", "libc")
+		path, _ := c.LibcPath("picolibc")
+		cflags = append(cflags,
+			"--sysroot="+path,
+			"-isystem", filepath.Join(path, "include"), // necessary for Xtensa
+			"-isystem", filepath.Join(picolibcDir, "include"),
+			"-isystem", filepath.Join(picolibcDir, "tinystdio"),
+		)
+	case "musl":
+		root := goenv.Get("TINYGOROOT")
+		path, _ := c.LibcPath("musl")
+		arch := MuslArchitecture(c.Triple())
+		cflags = append(cflags,
+			"-nostdlibinc",
+			"-isystem", filepath.Join(path, "include"),
+			"-isystem", filepath.Join(root, "lib", "musl", "arch", arch),
+			"-isystem", filepath.Join(root, "lib", "musl", "include"),
+		)
+	case "wasi-libc":
+		root := goenv.Get("TINYGOROOT")
+		cflags = append(cflags, "--sysroot="+root+"/lib/wasi-libc/sysroot")
+	case "mingw-w64":
+		root := goenv.Get("TINYGOROOT")
+		path, _ := c.LibcPath("mingw-w64")
+		cflags = append(cflags,
+			"--sysroot="+path,
+			"-isystem", filepath.Join(root, "lib", "mingw-w64", "mingw-w64-headers", "crt"),
+			"-isystem", filepath.Join(root, "lib", "mingw-w64", "mingw-w64-headers", "defaults", "include"),
+			"-D_UCRT",
+		)
+	case "":
+		// No libc specified, nothing to add.
+	default:
+		// Incorrect configuration. This could be handled in a better way, but
+		// usually this will be found by developers (not by TinyGo users).
+		panic("unknown libc: " + c.Target.Libc)
 	}
-	if c.Debug() {
-		cflags = append(cflags, "-g")
+	// Always emit debug information. It is optionally stripped at link time.
+	cflags = append(cflags, "-g")
+	// Use the same optimization level as TinyGo.
+	cflags = append(cflags, "-O"+c.Options.Opt)
+	// Set the LLVM target triple.
+	cflags = append(cflags, "--target="+c.Triple())
+	// Set the -mcpu (or similar) flag.
+	if c.Target.CPU != "" {
+		if c.GOARCH() == "amd64" || c.GOARCH() == "386" {
+			// x86 prefers the -march flag (-mcpu is deprecated there).
+			cflags = append(cflags, "-march="+c.Target.CPU)
+		} else if strings.HasPrefix(c.Triple(), "avr") {
+			// AVR MCUs use -mmcu instead of -mcpu.
+			cflags = append(cflags, "-mmcu="+c.Target.CPU)
+		} else {
+			// The rest just uses -mcpu.
+			cflags = append(cflags, "-mcpu="+c.Target.CPU)
+		}
 	}
 	return cflags
 }
@@ -184,7 +340,7 @@ func (c *Config) CFlags() []string {
 func (c *Config) LDFlags() []string {
 	root := goenv.Get("TINYGOROOT")
 	// Merge and adjust LDFlags.
-	ldflags := append([]string{}, c.Options.LDFlags...)
+	var ldflags []string
 	for _, flag := range c.Target.LDFlags {
 		ldflags = append(ldflags, strings.ReplaceAll(flag, "{root}", root))
 	}
@@ -213,8 +369,9 @@ func (c *Config) VerifyIR() bool {
 	return c.Options.VerifyIR
 }
 
-// Debug returns whether to add debug symbols to the IR, for debugging with GDB
-// and similar.
+// Debug returns whether debug (DWARF) information should be retained by the
+// linker. By default, debug information is retained but it can be removed with
+// the -no-debug flag.
 func (c *Config) Debug() bool {
 	return c.Options.Debug
 }
@@ -229,6 +386,13 @@ func (c *Config) BinaryFormat(ext string) string {
 			return c.Target.BinaryFormat
 		}
 		return "bin"
+	case ".img":
+		// Image file. Only defined for the ESP32 at the moment, where it is a
+		// full (runnable) image that can be used in the Espressif QEMU fork.
+		if c.Target.BinaryFormat != "" {
+			return c.Target.BinaryFormat + "-img"
+		}
+		return "bin"
 	case ".hex":
 		// Similar to bin, but includes the start address and is thus usually a
 		// better format.
@@ -238,6 +402,11 @@ func (c *Config) BinaryFormat(ext string) string {
 		// More information:
 		// https://github.com/Microsoft/uf2
 		return "uf2"
+	case ".zip":
+		if c.Target.BinaryFormat != "" {
+			return c.Target.BinaryFormat
+		}
+		return "zip"
 	default:
 		// Use the ELF format for unrecognized file formats.
 		return "elf"
@@ -255,6 +424,9 @@ func (c *Config) Programmer() (method, openocdInterface string) {
 	case "openocd", "msd", "command":
 		// The -programmer flag only specifies the flash method.
 		return c.Options.Programmer, c.Target.OpenOCDInterface
+	case "bmp":
+		// The -programmer flag only specifies the flash method.
+		return c.Options.Programmer, ""
 	default:
 		// The -programmer flag specifies something else, assume it specifies
 		// the OpenOCD interface name.
@@ -321,6 +493,45 @@ func (c *Config) WasmAbi() string {
 	return c.Target.WasmAbi
 }
 
+// EmulatorName is a shorthand to get the command for this emulator, something
+// like qemu-system-arm or simavr.
+func (c *Config) EmulatorName() string {
+	parts := strings.SplitN(c.Target.Emulator, " ", 2)
+	if len(parts) > 1 {
+		return parts[0]
+	}
+	return ""
+}
+
+// EmulatorFormat returns the binary format for the emulator and the associated
+// file extension. An empty string means to pass directly whatever the linker
+// produces directly without conversion (usually ELF format).
+func (c *Config) EmulatorFormat() (format, fileExt string) {
+	switch {
+	case strings.Contains(c.Target.Emulator, "{img}"):
+		return "img", ".img"
+	default:
+		return "", ""
+	}
+}
+
+// Emulator returns a ready-to-run command to run the given binary in an
+// emulator. Give it the format (returned by EmulatorFormat()) and the path to
+// the compiled binary.
+func (c *Config) Emulator(format, binary string) ([]string, error) {
+	parts, err := shlex.Split(c.Target.Emulator)
+	if err != nil {
+		return nil, fmt.Errorf("could not parse emulator command: %w", err)
+	}
+	var emulator []string
+	for _, s := range parts {
+		s = strings.ReplaceAll(s, "{root}", goenv.Get("TINYGOROOT"))
+		s = strings.ReplaceAll(s, "{"+format+"}", binary)
+		emulator = append(emulator, s)
+	}
+	return emulator, nil
+}
+
 type TestConfig struct {
 	CompileTestBinary bool
 	// TODO: Filter the test functions to run, include verbose flag, etc

compileopts/options.go

@@ -2,37 +2,51 @@ package compileopts
 
 import (
 	"fmt"
+	"regexp"
 	"strings"
 )
 
 var (
-	validGCOptions            = []string{"none", "leaking", "extalloc", "conservative"}
-	validSchedulerOptions     = []string{"none", "tasks", "coroutines"}
+	validGCOptions            = []string{"none", "leaking", "conservative"}
+	validSchedulerOptions     = []string{"none", "tasks", "asyncify"}
+	validSerialOptions        = []string{"none", "uart", "usb"}
 	validPrintSizeOptions     = []string{"none", "short", "full"}
 	validPanicStrategyOptions = []string{"print", "trap"}
+	validOptOptions           = []string{"none", "0", "1", "2", "s", "z"}
 )
 
 // Options contains extra options to give to the compiler. These options are
-// usually passed from the command line.
+// usually passed from the command line, but can also be passed in environment
+// variables for example.
 type Options struct {
-	Target        string
-	Opt           string
-	GC            string
-	PanicStrategy string
-	Scheduler     string
-	PrintIR       bool
-	DumpSSA       bool
-	VerifyIR      bool
-	PrintCommands bool
-	Debug         bool
-	PrintSizes    string
-	PrintStacks   bool
-	CFlags        []string
-	LDFlags       []string
-	Tags          string
-	WasmAbi       string
-	TestConfig    TestConfig
-	Programmer    string
+	GOOS            string // environment variable
+	GOARCH          string // environment variable
+	GOARM           string // environment variable (only used with GOARCH=arm)
+	Target          string
+	Opt             string
+	GC              string
+	PanicStrategy   string
+	Scheduler       string
+	Serial          string
+	Work            bool // -work flag to print temporary build directory
+	PrintIR         bool
+	DumpSSA         bool
+	VerifyIR        bool
+	PrintCommands   func(cmd string, args ...string) `json:"-"`
+	Semaphore       chan struct{}                    `json:"-"` // -p flag controls cap
+	Debug           bool
+	PrintSizes      string
+	PrintAllocs     *regexp.Regexp // regexp string
+	PrintStacks     bool
+	Tags            string
+	WasmAbi         string
+	GlobalValues    map[string]map[string]string // map[pkgpath]map[varname]value
+	TestConfig      TestConfig
+	Programmer      string
+	OpenOCDCommands []string
+	LLVMFeatures    string
+	Directory       string
+	PrintJSON       bool
 }
 
 // Verify performs a validation on the given options, raising an error if options are not valid.
@@ -55,6 +69,15 @@ func (o *Options) Verify() error {
 		}
 	}
 
+	if o.Serial != "" {
+		valid := isInArray(validSerialOptions, o.Serial)
+		if !valid {
+			return fmt.Errorf(`invalid serial option '%s': valid values are %s`,
+				o.Serial,
+				strings.Join(validSerialOptions, ", "))
+		}
+	}
+
 	if o.PrintSizes != "" {
 		valid := isInArray(validPrintSizeOptions, o.PrintSizes)
 		if !valid {
@@ -73,6 +96,12 @@ func (o *Options) Verify() error {
 		}
 	}
 
+	if o.Opt != "" {
+		if !isInArray(validOptOptions, o.Opt) {
+			return fmt.Errorf("invalid -opt=%s: valid values are %s", o.Opt, strings.Join(validOptOptions, ", "))
+		}
+	}
+
 	return nil
 }
 

compileopts/options_test.go

@@ -9,8 +9,8 @@ import (
 
 func TestVerifyOptions(t *testing.T) {
 
-	expectedGCError := errors.New(`invalid gc option 'incorrect': valid values are none, leaking, extalloc, conservative`)
-	expectedSchedulerError := errors.New(`invalid scheduler option 'incorrect': valid values are none, tasks, coroutines`)
+	expectedGCError := errors.New(`invalid gc option 'incorrect': valid values are none, leaking, conservative`)
+	expectedSchedulerError := errors.New(`invalid scheduler option 'incorrect': valid values are none, tasks, asyncify`)
 	expectedPrintSizeError := errors.New(`invalid size option 'incorrect': valid values are none, short, full`)
 	expectedPanicStrategyError := errors.New(`invalid panic option 'incorrect': valid values are print, trap`)
 
@@ -42,12 +42,6 @@ func TestVerifyOptions(t *testing.T) {
 				GC: "leaking",
 			},
 		},
-		{
-			name: "GCOptionExtalloc",
-			opts: compileopts.Options{
-				GC: "extalloc",
-			},
-		},
 		{
 			name: "GCOptionConservative",
 			opts: compileopts.Options{
@@ -73,12 +67,6 @@ func TestVerifyOptions(t *testing.T) {
 				Scheduler: "tasks",
 			},
 		},
-		{
-			name: "SchedulerOptionCoroutines",
-			opts: compileopts.Options{
-				Scheduler: "coroutines",
-			},
-		},
 		{
 			name: "InvalidPrintSizeOption",
 			opts: compileopts.Options{

compileopts/target.go

@@ -5,6 +5,7 @@ package compileopts
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io"
 	"os"
 	"os/exec"
@@ -25,13 +26,13 @@ type TargetSpec struct {
 	Inherits         []string `json:"inherits"`
 	Triple           string   `json:"llvm-target"`
 	CPU              string   `json:"cpu"`
-	Features         []string `json:"features"`
+	Features         string   `json:"features"`
 	GOOS             string   `json:"goos"`
 	GOARCH           string   `json:"goarch"`
 	BuildTags        []string `json:"build-tags"`
 	GC               string   `json:"gc"`
 	Scheduler        string   `json:"scheduler"`
-	Compiler         string   `json:"compiler"`
+	Serial           string   `json:"serial"` // which serial output to use (uart, usb, none)
 	Linker           string   `json:"linker"`
 	RTLib            string   `json:"rtlib"` // compiler runtime library (libgcc, compiler-rt)
 	Libc             string   `json:"libc"`
@@ -41,10 +42,12 @@ type TargetSpec struct {
 	LDFlags          []string `json:"ldflags"`
 	LinkerScript     string   `json:"linkerscript"`
 	ExtraFiles       []string `json:"extra-files"`
-	Emulator         []string `json:"emulator" override:"copy"` // inherited Emulator must not be append
+	RP2040BootPatch  *bool    `json:"rp2040-boot-patch"` // Patch RP2040 2nd stage bootloader checksum
+	Emulator         string   `json:"emulator"`
 	FlashCommand     string   `json:"flash-command"`
 	GDB              []string `json:"gdb"`
 	PortReset        string   `json:"flash-1200-bps-reset"`
+	SerialPort       []string `json:"serial-port"` // serial port IDs in the form "acm:vid:pid" or "usb:vid:pid"
 	FlashMethod      string   `json:"flash-method"`
 	FlashVolume      string   `json:"msd-volume-name"`
 	FlashFilename    string   `json:"msd-firmware-name"`
@@ -54,6 +57,7 @@ type TargetSpec struct {
 	OpenOCDTarget    string   `json:"openocd-target"`
 	OpenOCDTransport string   `json:"openocd-transport"`
 	OpenOCDCommands  []string `json:"openocd-commands"`
+	OpenOCDVerify    *bool    `json:"openocd-verify"` // enable verify when flashing with openocd
 	JLinkDevice      string   `json:"jlink-device"`
 	CodeModel        string   `json:"code-model"`
 	RelocationModel  string   `json:"relocation-model"`
@@ -84,19 +88,8 @@ func (spec *TargetSpec) overrideProperties(child *TargetSpec) {
 			if !src.IsNil() {
 				dst.Set(src)
 			}
-		case reflect.Slice: // for slices...
-			if src.Len() > 0 { // ... if not empty ...
-				switch tag := field.Tag.Get("override"); tag {
-				case "copy":
-					// copy the field of child to spec
-					dst.Set(src)
-				case "append", "":
-					// or append the field of child to spec
-					dst.Set(reflect.AppendSlice(src, dst))
-				default:
-					panic("override mode must be 'copy' or 'append' (default). I don't know how to '" + tag + "'.")
-				}
-			}
+		case reflect.Slice: // for slices, append the field
+			dst.Set(reflect.AppendSlice(dst, src))
 		default:
 			panic("unknown field type : " + kind.String())
 		}
@@ -159,121 +152,181 @@ func (spec *TargetSpec) resolveInherits() error {
 }
 
 // Load a target specification.
-func LoadTarget(target string) (*TargetSpec, error) {
-	if target == "" {
+func LoadTarget(options *Options) (*TargetSpec, error) {
+	if options.Target == "" {
 		// Configure based on GOOS/GOARCH environment variables (falling back to
 		// runtime.GOOS/runtime.GOARCH), and generate a LLVM target based on it.
-		goos := goenv.Get("GOOS")
-		goarch := goenv.Get("GOARCH")
-		llvmos := goos
-		llvmarch := map[string]string{
-			"386":   "i386",
-			"amd64": "x86_64",
-			"arm64": "aarch64",
-		}[goarch]
-		if llvmarch == "" {
-			llvmarch = goarch
+		var llvmarch string
+		switch options.GOARCH {
+		case "386":
+			llvmarch = "i386"
+		case "amd64":
+			llvmarch = "x86_64"
+		case "arm64":
+			llvmarch = "aarch64"
+		case "arm":
+			switch options.GOARM {
+			case "5":
+				llvmarch = "armv5"
+			case "6":
+				llvmarch = "armv6"
+			case "7":
+				llvmarch = "armv7"
+			default:
+				return nil, fmt.Errorf("invalid GOARM=%s, must be 5, 6, or 7", options.GOARM)
+			}
+		default:
+			llvmarch = options.GOARCH
 		}
-		target = llvmarch + "--" + llvmos
-		if goarch == "arm" {
+		llvmos := options.GOOS
+		if llvmos == "darwin" {
+			// Use macosx* instead of darwin, otherwise darwin/arm64 will refer
+			// to iOS!
+			llvmos = "macosx10.12.0"
+			if llvmarch == "aarch64" {
+				// Looks like Apple prefers to call this architecture ARM64
+				// instead of AArch64.
+				llvmarch = "arm64"
+			}
+		}
+		// Target triples (which actually have four components, but are called
+		// triples for historical reasons) have the form:
+		//   arch-vendor-os-environment
+		target := llvmarch + "-unknown-" + llvmos
+		if options.GOARCH == "arm" {
 			target += "-gnueabihf"
 		}
-		return defaultTarget(goos, goarch, target)
+		if options.GOOS == "windows" {
+			target += "-gnu"
+		}
+		return defaultTarget(options.GOOS, options.GOARCH, target)
 	}
 
 	// See whether there is a target specification for this target (e.g.
 	// Arduino).
 	spec := &TargetSpec{}
-	err := spec.loadFromGivenStr(target)
-	if err == nil {
-		// Successfully loaded this target from a built-in .json file. Make sure
-		// it includes all parents as specified in the "inherits" key.
-		err = spec.resolveInherits()
-		if err != nil {
-			return nil, err
-		}
-		return spec, nil
-	} else if !os.IsNotExist(err) {
-		// Expected a 'file not found' error, got something else. Report it as
-		// an error.
+	err := spec.loadFromGivenStr(options.Target)
+	if err != nil {
 		return nil, err
-	} else {
-		// Load target from given triple, ignore GOOS/GOARCH environment
-		// variables.
-		tripleSplit := strings.Split(target, "-")
-		if len(tripleSplit) < 3 {
-			return nil, errors.New("expected a full LLVM target or a custom target in -target flag")
-		}
-		if tripleSplit[0] == "arm" {
-			// LLVM and Clang have a different idea of what "arm" means, so
-			// upgrade to a slightly more modern ARM. In fact, when you pass
-			// --target=arm--linux-gnueabihf to Clang, it will convert that
-			// internally to armv7-unknown-linux-gnueabihf. Changing the
-			// architecture to armv7 will keep things consistent.
-			tripleSplit[0] = "armv7"
-		}
-		goos := tripleSplit[2]
-		if strings.HasPrefix(goos, "darwin") {
-			goos = "darwin"
-		}
-		goarch := map[string]string{ // map from LLVM arch to Go arch
-			"i386":    "386",
-			"i686":    "386",
-			"x86_64":  "amd64",
-			"aarch64": "arm64",
-			"armv7":   "arm",
-		}[tripleSplit[0]]
-		if goarch == "" {
-			goarch = tripleSplit[0]
-		}
-		return defaultTarget(goos, goarch, strings.Join(tripleSplit, "-"))
 	}
+	// Successfully loaded this target from a built-in .json file. Make sure
+	// it includes all parents as specified in the "inherits" key.
+	err = spec.resolveInherits()
+	if err != nil {
+		return nil, err
+	}
+
+	if spec.Scheduler == "asyncify" {
+		spec.ExtraFiles = append(spec.ExtraFiles, "src/internal/task/task_asyncify_wasm.S")
+	}
+
+	return spec, nil
 }
 
-// WindowsBuildNotSupportedErr is being thrown, when goos is windows and no target has been specified.
-var WindowsBuildNotSupportedErr = errors.New("Building Windows binaries is currently not supported. Try specifying a different target")
-
 func defaultTarget(goos, goarch, triple string) (*TargetSpec, error) {
-	if goos == "windows" {
-		return nil, WindowsBuildNotSupportedErr
-	}
 	// No target spec available. Use the default one, useful on most systems
 	// with a regular OS.
 	spec := TargetSpec{
-		Triple:    triple,
-		GOOS:      goos,
-		GOARCH:    goarch,
-		BuildTags: []string{goos, goarch},
-		Compiler:  "clang",
-		Linker:    "cc",
-		CFlags:    []string{"--target=" + triple},
-		GDB:       []string{"gdb"},
-		PortReset: "false",
+		Triple:           triple,
+		GOOS:             goos,
+		GOARCH:           goarch,
+		BuildTags:        []string{goos, goarch},
+		Scheduler:        "tasks",
+		Linker:           "cc",
+		DefaultStackSize: 1024 * 64, // 64kB
+		GDB:              []string{"gdb"},
+		PortReset:        "false",
+	}
+	switch goarch {
+	case "386":
+		spec.CPU = "pentium4"
+		spec.Features = "+cx8,+fxsr,+mmx,+sse,+sse2,+x87"
+	case "amd64":
+		spec.CPU = "x86-64"
+		spec.Features = "+cx8,+fxsr,+mmx,+sse,+sse2,+x87"
+	case "arm":
+		spec.CPU = "generic"
+		spec.CFlags = append(spec.CFlags, "-fno-unwind-tables", "-fno-asynchronous-unwind-tables")
+		switch strings.Split(triple, "-")[0] {
+		case "armv5":
+			spec.Features = "+armv5t,+strict-align,-aes,-bf16,-d32,-dotprod,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-mve.fp,-neon,-sha2,-thumb-mode,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+		case "armv6":
+			spec.Features = "+armv6,+dsp,+fp64,+strict-align,+vfp2,+vfp2sp,-aes,-d32,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fullfp16,-neon,-sha2,-thumb-mode,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+		case "armv7":
+			spec.Features = "+armv7-a,+d32,+dsp,+fp64,+neon,+vfp2,+vfp2sp,+vfp3,+vfp3d16,+vfp3d16sp,+vfp3sp,-aes,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fullfp16,-sha2,-thumb-mode,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+		}
+	case "arm64":
+		spec.CPU = "generic"
+		spec.Features = "+neon"
 	}
 	if goos == "darwin" {
-		spec.LDFlags = append(spec.LDFlags, "-Wl,-dead_strip")
+		spec.Linker = "ld.lld"
+		spec.Libc = "darwin-libSystem"
+		arch := strings.Split(triple, "-")[0]
+		platformVersion := strings.TrimPrefix(strings.Split(triple, "-")[2], "macosx")
+		spec.LDFlags = append(spec.LDFlags,
+			"-flavor", "darwin",
+			"-dead_strip",
+			"-arch", arch,
+			"-platform_version", "macos", platformVersion, platformVersion,
+		)
+	} else if goos == "linux" {
+		spec.Linker = "ld.lld"
+		spec.RTLib = "compiler-rt"
+		spec.Libc = "musl"
+		spec.LDFlags = append(spec.LDFlags, "--gc-sections")
+	} else if goos == "windows" {
+		spec.Linker = "ld.lld"
+		spec.Libc = "mingw-w64"
+		// Note: using a medium code model, low image base and no ASLR
+		// because Go doesn't really need those features. ASLR patches
+		// around issues for unsafe languages like C/C++ that are not
+		// normally present in Go (without explicitly opting in).
+		// For more discussion:
+		// https://groups.google.com/g/Golang-nuts/c/Jd9tlNc6jUE/m/Zo-7zIP_m3MJ?pli=1
+		spec.LDFlags = append(spec.LDFlags,
+			"-m", "i386pep",
+			"-Bdynamic",
+			"--image-base", "0x400000",
+			"--gc-sections",
+			"--no-insert-timestamp",
+			"--no-dynamicbase",
+		)
 	} else {
 		spec.LDFlags = append(spec.LDFlags, "-no-pie", "-Wl,--gc-sections") // WARNING: clang < 5.0 requires -nopie
 	}
 	if goarch != "wasm" {
-		spec.ExtraFiles = append(spec.ExtraFiles, "src/runtime/gc_"+goarch+".S")
+		suffix := ""
+		if goos == "windows" {
+			// Windows uses a different calling convention from other operating
+			// systems so we need separate assembly files.
+			suffix = "_windows"
+		}
+		spec.ExtraFiles = append(spec.ExtraFiles, "src/runtime/gc_"+goarch+suffix+".S")
+		spec.ExtraFiles = append(spec.ExtraFiles, "src/internal/task/task_stack_"+goarch+suffix+".S")
 	}
 	if goarch != runtime.GOARCH {
 		// Some educated guesses as to how to invoke helper programs.
 		spec.GDB = []string{"gdb-multiarch"}
-		if goarch == "arm" && goos == "linux" {
-			spec.CFlags = append(spec.CFlags, "--sysroot=/usr/arm-linux-gnueabihf")
-			spec.Linker = "arm-linux-gnueabihf-gcc"
-			spec.Emulator = []string{"qemu-arm", "-L", "/usr/arm-linux-gnueabihf"}
+		if goos == "linux" {
+			switch goarch {
+			case "386":
+				// amd64 can _usually_ run 32-bit programs, so skip the emulator in that case.
+				if runtime.GOARCH != "amd64" {
+					spec.Emulator = "qemu-i386 {}"
+				}
+			case "amd64":
+				spec.Emulator = "qemu-x86_64 {}"
+			case "arm":
+				spec.Emulator = "qemu-arm {}"
+			case "arm64":
+				spec.Emulator = "qemu-aarch64 {}"
+			}
 		}
-		if goarch == "arm64" && goos == "linux" {
-			spec.CFlags = append(spec.CFlags, "--sysroot=/usr/aarch64-linux-gnu")
-			spec.Linker = "aarch64-linux-gnu-gcc"
-			spec.Emulator = []string{"qemu-aarch64", "-L", "/usr/aarch64-linux-gnu"}
-		}
-		if goarch == "386" && runtime.GOARCH == "amd64" {
-			spec.CFlags = append(spec.CFlags, "-m32")
-			spec.LDFlags = append(spec.LDFlags, "-m32")
+	}
+	if goos != runtime.GOOS {
+		if goos == "windows" {
+			spec.Emulator = "wine {}"
 		}
 	}
 	return &spec, nil

compileopts/target_test.go

@@ -1,22 +1,23 @@
 package compileopts
 
 import (
+	"os"
 	"reflect"
 	"testing"
 )
 
 func TestLoadTarget(t *testing.T) {
-	_, err := LoadTarget("arduino")
+	_, err := LoadTarget(&Options{Target: "arduino"})
 	if err != nil {
 		t.Error("LoadTarget test failed:", err)
 	}
 
-	_, err = LoadTarget("notexist")
+	_, err = LoadTarget(&Options{Target: "notexist"})
 	if err == nil {
 		t.Error("LoadTarget should have failed with non existing target")
 	}
 
-	if err.Error() != "expected a full LLVM target or a custom target in -target flag" {
+	if !os.IsNotExist(err) {
 		t.Error("LoadTarget failed for wrong reason:", err)
 	}
 }
@@ -26,9 +27,8 @@ func TestOverrideProperties(t *testing.T) {
 	base := &TargetSpec{
 		GOOS:             "baseGoos",
 		CPU:              "baseCpu",
-		Features:         []string{"bf1", "bf2"},
+		CFlags:           []string{"-base-foo", "-base-bar"},
 		BuildTags:        []string{"bt1", "bt2"},
-		Emulator:         []string{"be1", "be2"},
 		DefaultStackSize: 42,
 		AutoStackSize:    &baseAutoStackSize,
 	}
@@ -36,8 +36,7 @@ func TestOverrideProperties(t *testing.T) {
 	child := &TargetSpec{
 		GOOS:             "",
 		CPU:              "chlidCpu",
-		Features:         []string{"cf1", "cf2"},
-		Emulator:         []string{"ce1", "ce2"},
+		CFlags:           []string{"-child-foo", "-child-bar"},
 		AutoStackSize:    &childAutoStackSize,
 		DefaultStackSize: 64,
 	}
@@ -50,15 +49,12 @@ func TestOverrideProperties(t *testing.T) {
 	if base.CPU != "chlidCpu" {
 		t.Errorf("Overriding failed : got %v", base.CPU)
 	}
-	if !reflect.DeepEqual(base.Features, []string{"cf1", "cf2", "bf1", "bf2"}) {
-		t.Errorf("Overriding failed : got %v", base.Features)
+	if !reflect.DeepEqual(base.CFlags, []string{"-base-foo", "-base-bar", "-child-foo", "-child-bar"}) {
+		t.Errorf("Overriding failed : got %v", base.CFlags)
 	}
 	if !reflect.DeepEqual(base.BuildTags, []string{"bt1", "bt2"}) {
 		t.Errorf("Overriding failed : got %v", base.BuildTags)
 	}
-	if !reflect.DeepEqual(base.Emulator, []string{"ce1", "ce2"}) {
-		t.Errorf("Overriding failed : got %v", base.Emulator)
-	}
 	if *base.AutoStackSize != false {
 		t.Errorf("Overriding failed : got %v", base.AutoStackSize)
 	}

compiler/alias.go

@@ -0,0 +1,102 @@
+package compiler
+
+// This file defines alias functions for functions that are normally defined in
+// Go assembly.
+//
+// The Go toolchain defines many performance critical functions in assembly
+// instead of plain Go. This is a problem for TinyGo as it currently (as of
+// august 2021) is not able to compile these assembly files and even if it
+// could, it would not be able to make use of them for many targets that are
+// supported by TinyGo (baremetal RISC-V, AVR, etc). Therefore, many of these
+// functions are aliased to their generic Go implementation.
+// This results in slower than possible implementations, but at least they are
+// usable.
+
+import "tinygo.org/x/go-llvm"
+
+var stdlibAliases = map[string]string{
+	// crypto packages
+	"crypto/md5.block":         "crypto/md5.blockGeneric",
+	"crypto/sha1.block":        "crypto/sha1.blockGeneric",
+	"crypto/sha1.blockAMD64":   "crypto/sha1.blockGeneric",
+	"crypto/sha256.block":      "crypto/sha256.blockGeneric",
+	"crypto/sha512.blockAMD64": "crypto/sha512.blockGeneric",
+
+	// math package
+	"math.Asin":      "math.asin",
+	"math.Asinh":     "math.asinh",
+	"math.Acos":      "math.acos",
+	"math.Acosh":     "math.acosh",
+	"math.Atan":      "math.atan",
+	"math.Atanh":     "math.atanh",
+	"math.Atan2":     "math.atan2",
+	"math.Cbrt":      "math.cbrt",
+	"math.Ceil":      "math.ceil",
+	"math.archCeil":  "math.ceil",
+	"math.Cos":       "math.cos",
+	"math.Cosh":      "math.cosh",
+	"math.Erf":       "math.erf",
+	"math.Erfc":      "math.erfc",
+	"math.Exp":       "math.exp",
+	"math.archExp":   "math.exp",
+	"math.Expm1":     "math.expm1",
+	"math.Exp2":      "math.exp2",
+	"math.archExp2":  "math.exp2",
+	"math.Floor":     "math.floor",
+	"math.archFloor": "math.floor",
+	"math.Frexp":     "math.frexp",
+	"math.Hypot":     "math.hypot",
+	"math.archHypot": "math.hypot",
+	"math.Ldexp":     "math.ldexp",
+	"math.Log":       "math.log",
+	"math.archLog":   "math.log",
+	"math.Log1p":     "math.log1p",
+	"math.Log10":     "math.log10",
+	"math.Log2":      "math.log2",
+	"math.Max":       "math.max",
+	"math.archMax":   "math.max",
+	"math.Min":       "math.min",
+	"math.archMin":   "math.min",
+	"math.Mod":       "math.mod",
+	"math.Modf":      "math.modf",
+	"math.archModf":  "math.modf",
+	"math.Pow":       "math.pow",
+	"math.Remainder": "math.remainder",
+	"math.Sin":       "math.sin",
+	"math.Sinh":      "math.sinh",
+	"math.Sqrt":      "math.sqrt",
+	"math.archSqrt":  "math.sqrt",
+	"math.Tan":       "math.tan",
+	"math.Tanh":      "math.tanh",
+	"math.Trunc":     "math.trunc",
+	"math.archTrunc": "math.trunc",
+}
+
+// createAlias implements the function (in the builder) as a call to the alias
+// function.
+func (b *builder) createAlias(alias llvm.Value) {
+	b.llvmFn.SetVisibility(llvm.HiddenVisibility)
+	b.llvmFn.SetUnnamedAddr(true)
+
+	if b.Debug {
+		if b.fn.Syntax() != nil {
+			// Create debug info file if present.
+			b.difunc = b.attachDebugInfo(b.fn)
+		}
+		pos := b.program.Fset.Position(b.fn.Pos())
+		b.SetCurrentDebugLocation(uint(pos.Line), uint(pos.Column), b.difunc, llvm.Metadata{})
+	}
+	entryBlock := llvm.AddBasicBlock(b.llvmFn, "entry")
+	b.SetInsertPointAtEnd(entryBlock)
+	if b.llvmFn.Type() != alias.Type() {
+		b.addError(b.fn.Pos(), "alias function should have the same type as aliasee "+alias.Name())
+		b.CreateUnreachable()
+		return
+	}
+	result := b.CreateCall(alias, b.llvmFn.Params(), "")
+	if result.Type().TypeKind() == llvm.VoidTypeKind {
+		b.CreateRetVoid()
+	} else {
+		b.CreateRet(result)
+	}
+}

compiler/asserts.go

@@ -15,22 +15,16 @@ import (
 // createLookupBoundsCheck emits a bounds check before doing a lookup into a
 // slice. This is required by the Go language spec: an index out of bounds must
 // cause a panic.
-func (b *builder) createLookupBoundsCheck(arrayLen, index llvm.Value, indexType types.Type) {
+// The caller should make sure that index is at least as big as arrayLen.
+func (b *builder) createLookupBoundsCheck(arrayLen, index llvm.Value) {
 	if b.info.nobounds {
 		// The //go:nobounds pragma was added to the function to avoid bounds
 		// checking.
 		return
 	}
 
-	if index.Type().IntTypeWidth() < arrayLen.Type().IntTypeWidth() {
-		// Sometimes, the index can be e.g. an uint8 or int8, and we have to
-		// correctly extend that type.
-		if indexType.Underlying().(*types.Basic).Info()&types.IsUnsigned == 0 {
-			index = b.CreateZExt(index, arrayLen.Type(), "")
-		} else {
-			index = b.CreateSExt(index, arrayLen.Type(), "")
-		}
-	} else if index.Type().IntTypeWidth() > arrayLen.Type().IntTypeWidth() {
+	// Extend arrayLen if it's too small.
+	if index.Type().IntTypeWidth() > arrayLen.Type().IntTypeWidth() {
 		// The index is bigger than the array length type, so extend it.
 		arrayLen = b.CreateZExt(arrayLen, index.Type(), "")
 	}
@@ -70,27 +64,9 @@ func (b *builder) createSliceBoundsCheck(capacity, low, high, max llvm.Value, lo
 	}
 
 	// Extend low and high to be the same size as capacity.
-	if low.Type().IntTypeWidth() < capacityType.IntTypeWidth() {
-		if lowType.Info()&types.IsUnsigned != 0 {
-			low = b.CreateZExt(low, capacityType, "")
-		} else {
-			low = b.CreateSExt(low, capacityType, "")
-		}
-	}
-	if high.Type().IntTypeWidth() < capacityType.IntTypeWidth() {
-		if highType.Info()&types.IsUnsigned != 0 {
-			high = b.CreateZExt(high, capacityType, "")
-		} else {
-			high = b.CreateSExt(high, capacityType, "")
-		}
-	}
-	if max.Type().IntTypeWidth() < capacityType.IntTypeWidth() {
-		if maxType.Info()&types.IsUnsigned != 0 {
-			max = b.CreateZExt(max, capacityType, "")
-		} else {
-			max = b.CreateSExt(max, capacityType, "")
-		}
-	}
+	low = b.extendInteger(low, lowType, capacityType)
+	high = b.extendInteger(high, highType, capacityType)
+	max = b.extendInteger(max, maxType, capacityType)
 
 	// Now do the bounds check: low > high || high > capacity
 	outOfBounds1 := b.CreateICmp(llvm.IntUGT, low, high, "slice.lowhigh")
@@ -101,6 +77,49 @@ func (b *builder) createSliceBoundsCheck(capacity, low, high, max llvm.Value, lo
 	b.createRuntimeAssert(outOfBounds, "slice", "slicePanic")
 }
 
+// createSliceToArrayPointerCheck adds a check for slice-to-array pointer
+// conversions. This conversion was added in Go 1.17. For details, see:
+// https://tip.golang.org/ref/spec#Conversions_from_slice_to_array_pointer
+func (b *builder) createSliceToArrayPointerCheck(sliceLen llvm.Value, arrayLen int64) {
+	// From the spec:
+	// > If the length of the slice is less than the length of the array, a
+	// > run-time panic occurs.
+	arrayLenValue := llvm.ConstInt(b.uintptrType, uint64(arrayLen), false)
+	isLess := b.CreateICmp(llvm.IntULT, sliceLen, arrayLenValue, "")
+	b.createRuntimeAssert(isLess, "slicetoarray", "sliceToArrayPointerPanic")
+}
+
+// createUnsafeSliceCheck inserts a runtime check used for unsafe.Slice. This
+// function must panic if the ptr/len parameters are invalid.
+func (b *builder) createUnsafeSliceCheck(ptr, len llvm.Value, lenType *types.Basic) {
+	// From the documentation of unsafe.Slice:
+	//   > At run time, if len is negative, or if ptr is nil and len is not
+	//   > zero, a run-time panic occurs.
+	// However, in practice, it is also necessary to check that the length is
+	// not too big that a GEP wouldn't be possible without wrapping the pointer.
+	// These two checks (non-negative and not too big) can be merged into one
+	// using an unsiged greater than.
+
+	// Make sure the len value is at least as big as a uintptr.
+	len = b.extendInteger(len, lenType, b.uintptrType)
+
+	// Determine the maximum slice size, and therefore the maximum value of the
+	// len parameter.
+	maxSize := b.maxSliceSize(ptr.Type().ElementType())
+	maxSizeValue := llvm.ConstInt(len.Type(), maxSize, false)
+
+	// Do the check. By using unsigned greater than for the length check, signed
+	// negative values are also checked (which are very large numbers when
+	// interpreted as signed values).
+	zero := llvm.ConstInt(len.Type(), 0, false)
+	lenOutOfBounds := b.CreateICmp(llvm.IntUGT, len, maxSizeValue, "")
+	ptrIsNil := b.CreateICmp(llvm.IntEQ, ptr, llvm.ConstNull(ptr.Type()), "")
+	lenIsNotZero := b.CreateICmp(llvm.IntNE, len, zero, "")
+	assert := b.CreateAnd(ptrIsNil, lenIsNotZero, "")
+	assert = b.CreateOr(assert, lenOutOfBounds, "")
+	b.createRuntimeAssert(assert, "unsafe.Slice", "unsafeSlicePanic")
+}
+
 // createChanBoundsCheck creates a bounds check before creating a new channel to
 // check that the value is not too big for runtime.chanMake.
 func (b *builder) createChanBoundsCheck(elementSize uint64, bufSize llvm.Value, bufSizeType *types.Basic, pos token.Pos) {
@@ -110,19 +129,8 @@ func (b *builder) createChanBoundsCheck(elementSize uint64, bufSize llvm.Value,
 		return
 	}
 
-	// Check whether the bufSize parameter must be cast to a wider integer for
-	// comparison.
-	if bufSize.Type().IntTypeWidth() < b.uintptrType.IntTypeWidth() {
-		if bufSizeType.Info()&types.IsUnsigned != 0 {
-			// Unsigned, so zero-extend to uint type.
-			bufSizeType = types.Typ[types.Uint]
-			bufSize = b.CreateZExt(bufSize, b.intType, "")
-		} else {
-			// Signed, so sign-extend to int type.
-			bufSizeType = types.Typ[types.Int]
-			bufSize = b.CreateSExt(bufSize, b.intType, "")
-		}
-	}
+	// Make sure bufSize is at least as big as maxBufSize (an uintptr).
+	bufSize = b.extendInteger(bufSize, bufSizeType, b.uintptrType)
 
 	// Calculate (^uintptr(0)) >> 1, which is the max value that fits in an
 	// uintptr if uintptrs were signed.
@@ -162,6 +170,10 @@ func (b *builder) createNilCheck(inst ssa.Value, ptr llvm.Value, blockPrefix str
 	case *ssa.Alloc:
 		// An alloc is never nil.
 		return
+	case *ssa.FreeVar:
+		// A free variable is allocated in a parent function and is thus never
+		// nil.
+		return
 	case *ssa.IndexAddr:
 		// This pointer is the result of an index operation into a slice or
 		// array. Such slices/arrays are already bounds checked so the pointer
@@ -202,6 +214,19 @@ func (b *builder) createNegativeShiftCheck(shift llvm.Value) {
 	b.createRuntimeAssert(isNegative, "shift", "negativeShiftPanic")
 }
 
+// createDivideByZeroCheck asserts that y is not zero. If it is, a runtime panic
+// will be emitted. This follows the Go specification which says that a divide
+// by zero must cause a run time panic.
+func (b *builder) createDivideByZeroCheck(y llvm.Value) {
+	if b.info.nobounds {
+		return
+	}
+
+	// isZero = y == 0
+	isZero := b.CreateICmp(llvm.IntEQ, y, llvm.ConstInt(y.Type(), 0, false), "")
+	b.createRuntimeAssert(isZero, "divbyzero", "divideByZeroPanic")
+}
+
 // createRuntimeAssert is a common function to create a new branch on an assert
 // bool, calling an assert func if the assert value is true (1).
 func (b *builder) createRuntimeAssert(assert llvm.Value, blockPrefix, assertFunc string) {
@@ -230,3 +255,19 @@ func (b *builder) createRuntimeAssert(assert llvm.Value, blockPrefix, assertFunc
 	// Ok: assert didn't trigger so continue normally.
 	b.SetInsertPointAtEnd(nextBlock)
 }
+
+// extendInteger extends the value to at least targetType using a zero or sign
+// extend. The resulting value is not truncated: it may still be bigger than
+// targetType.
+func (b *builder) extendInteger(value llvm.Value, valueType types.Type, targetType llvm.Type) llvm.Value {
+	if value.Type().IntTypeWidth() < targetType.IntTypeWidth() {
+		if valueType.Underlying().(*types.Basic).Info()&types.IsUnsigned != 0 {
+			// Unsigned, so zero-extend to the target type.
+			value = b.CreateZExt(value, targetType, "")
+		} else {
+			// Signed, so sign-extend to the target type.
+			value = b.CreateSExt(value, targetType, "")
+		}
+	}
+	return value
+}

compiler/atomic.go

@@ -1,6 +1,7 @@
 package compiler
 
 import (
+	"fmt"
 	"strings"
 
 	"golang.org/x/tools/go/ssa"
@@ -16,6 +17,20 @@ func (b *builder) createAtomicOp(call *ssa.CallCommon) (llvm.Value, bool) {
 	case "AddInt32", "AddInt64", "AddUint32", "AddUint64", "AddUintptr":
 		ptr := b.getValue(call.Args[0])
 		val := b.getValue(call.Args[1])
+		if strings.HasPrefix(b.Triple, "avr") {
+			// AtomicRMW does not work on AVR as intended:
+			// - There are some register allocation issues (fixed by https://reviews.llvm.org/D97127 which is not yet in a usable LLVM release)
+			// - The result is the new value instead of the old value
+			vType := val.Type()
+			name := fmt.Sprintf("__sync_fetch_and_add_%d", vType.IntTypeWidth()/8)
+			fn := b.mod.NamedFunction(name)
+			if fn.IsNil() {
+				fn = llvm.AddFunction(b.mod, name, llvm.FunctionType(vType, []llvm.Type{ptr.Type(), vType}, false))
+			}
+			oldVal := b.createCall(fn, []llvm.Value{ptr, val}, "")
+			// Return the new value, not the original value returned.
+			return b.CreateAdd(oldVal, val, ""), true
+		}
 		oldVal := b.CreateAtomicRMW(llvm.AtomicRMWBinOpAdd, ptr, val, llvm.AtomicOrderingSequentiallyConsistent, true)
 		// Return the new value, not the original value returned by atomicrmw.
 		return b.CreateAdd(oldVal, val, ""), true
@@ -37,31 +52,6 @@ func (b *builder) createAtomicOp(call *ssa.CallCommon) (llvm.Value, bool) {
 		ptr := b.getValue(call.Args[0])
 		old := b.getValue(call.Args[1])
 		newVal := b.getValue(call.Args[2])
-		if strings.HasSuffix(name, "64") {
-			arch := strings.Split(b.Triple, "-")[0]
-			if strings.HasPrefix(arch, "arm") && strings.HasSuffix(arch, "m") {
-				// Work around a bug in LLVM, at least LLVM 11:
-				// https://reviews.llvm.org/D95891
-				// Check for armv6m, armv7, armv7em, and perhaps others.
-				// See also: https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html
-				compareAndSwap := b.mod.NamedFunction("__sync_val_compare_and_swap_8")
-				if compareAndSwap.IsNil() {
-					// Declare the function if it isn't already declared.
-					i64Type := b.ctx.Int64Type()
-					fnType := llvm.FunctionType(i64Type, []llvm.Type{llvm.PointerType(i64Type, 0), i64Type, i64Type}, false)
-					compareAndSwap = llvm.AddFunction(b.mod, "__sync_val_compare_and_swap_8", fnType)
-				}
-				actualOldValue := b.CreateCall(compareAndSwap, []llvm.Value{ptr, old, newVal}, "")
-				// The __sync_val_compare_and_swap_8 function returns the old
-				// value. However, we shouldn't return the old value, we should
-				// return whether the compare/exchange was successful. This is
-				// easily done by comparing the returned (actual) old value with
-				// the expected old value passed to
-				// __sync_val_compare_and_swap_8.
-				swapped := b.CreateICmp(llvm.IntEQ, old, actualOldValue, "")
-				return swapped, true
-			}
-		}
 		tuple := b.CreateAtomicCmpXchg(ptr, old, newVal, llvm.AtomicOrderingSequentiallyConsistent, llvm.AtomicOrderingSequentiallyConsistent, true)
 		swapped := b.CreateExtractValue(tuple, 1, "")
 		return swapped, true
@@ -74,6 +64,23 @@ func (b *builder) createAtomicOp(call *ssa.CallCommon) (llvm.Value, bool) {
 	case "StoreInt32", "StoreInt64", "StoreUint32", "StoreUint64", "StoreUintptr", "StorePointer":
 		ptr := b.getValue(call.Args[0])
 		val := b.getValue(call.Args[1])
+		if strings.HasPrefix(b.Triple, "avr") {
+			// SelectionDAGBuilder is currently missing the "are unaligned atomics allowed" check for stores.
+			vType := val.Type()
+			isPointer := vType.TypeKind() == llvm.PointerTypeKind
+			if isPointer {
+				// libcalls only supports integers, so cast to an integer.
+				vType = b.uintptrType
+				val = b.CreatePtrToInt(val, vType, "")
+				ptr = b.CreateBitCast(ptr, llvm.PointerType(vType, 0), "")
+			}
+			name := fmt.Sprintf("__atomic_store_%d", vType.IntTypeWidth()/8)
+			fn := b.mod.NamedFunction(name)
+			if fn.IsNil() {
+				fn = llvm.AddFunction(b.mod, name, llvm.FunctionType(vType, []llvm.Type{ptr.Type(), vType, b.uintptrType}, false))
+			}
+			return b.createCall(fn, []llvm.Value{ptr, val, llvm.ConstInt(b.uintptrType, 5, false)}, ""), true
+		}
 		store := b.CreateStore(val, ptr)
 		store.SetOrdering(llvm.AtomicOrderingSequentiallyConsistent)
 		store.SetAlignment(b.targetData.PrefTypeAlignment(val.Type())) // required

compiler/calls.go

@@ -40,8 +40,7 @@ func (b *builder) createRuntimeCall(fnName string, args []llvm.Value, name strin
 	if llvmFn.IsNil() {
 		panic("trying to call non-existent function: " + fn.RelString(nil))
 	}
-	args = append(args, llvm.Undef(b.i8ptrType))            // unused context parameter
-	args = append(args, llvm.ConstPointerNull(b.i8ptrType)) // coroutine handle
+	args = append(args, llvm.Undef(b.i8ptrType)) // unused context parameter
 	return b.createCall(llvmFn, args, name)
 }
 
@@ -63,10 +62,10 @@ func (c *compilerContext) expandFormalParamType(t llvm.Type, name string, goType
 	case llvm.StructTypeKind:
 		fieldInfos := c.flattenAggregateType(t, name, goType)
 		if len(fieldInfos) <= maxFieldsPerParam {
+			// managed to expand this parameter
 			return fieldInfos
-		} else {
-			// failed to lower
 		}
+		// failed to expand this parameter: too many fields
 	}
 	// TODO: split small arrays
 	return []paramInfo{

compiler/channel.go

@@ -32,8 +32,15 @@ func (b *builder) createChanSend(instr *ssa.Send) {
 
 	// store value-to-send
 	valueType := b.getLLVMType(instr.X.Type())
-	valueAlloca, valueAllocaCast, valueAllocaSize := b.createTemporaryAlloca(valueType, "chan.value")
-	b.CreateStore(chanValue, valueAlloca)
+	isZeroSize := b.targetData.TypeAllocSize(valueType) == 0
+	var valueAlloca, valueAllocaCast, valueAllocaSize llvm.Value
+	if isZeroSize {
+		valueAlloca = llvm.ConstNull(llvm.PointerType(valueType, 0))
+		valueAllocaCast = llvm.ConstNull(b.i8ptrType)
+	} else {
+		valueAlloca, valueAllocaCast, valueAllocaSize = b.createTemporaryAlloca(valueType, "chan.value")
+		b.CreateStore(chanValue, valueAlloca)
+	}
 
 	// Allocate blockedlist buffer.
 	channelBlockedList := b.mod.GetTypeByName("runtime.channelBlockedList")
@@ -46,7 +53,9 @@ func (b *builder) createChanSend(instr *ssa.Send) {
 	// This also works around a bug in CoroSplit, at least in LLVM 8:
 	// https://bugs.llvm.org/show_bug.cgi?id=41742
 	b.emitLifetimeEnd(channelBlockedListAllocaCast, channelBlockedListAllocaSize)
-	b.emitLifetimeEnd(valueAllocaCast, valueAllocaSize)
+	if !isZeroSize {
+		b.emitLifetimeEnd(valueAllocaCast, valueAllocaSize)
+	}
 }
 
 // createChanRecv emits a pseudo chan receive operation. It is lowered to the
@@ -56,7 +65,14 @@ func (b *builder) createChanRecv(unop *ssa.UnOp) llvm.Value {
 	ch := b.getValue(unop.X)
 
 	// Allocate memory to receive into.
-	valueAlloca, valueAllocaCast, valueAllocaSize := b.createTemporaryAlloca(valueType, "chan.value")
+	isZeroSize := b.targetData.TypeAllocSize(valueType) == 0
+	var valueAlloca, valueAllocaCast, valueAllocaSize llvm.Value
+	if isZeroSize {
+		valueAlloca = llvm.ConstNull(llvm.PointerType(valueType, 0))
+		valueAllocaCast = llvm.ConstNull(b.i8ptrType)
+	} else {
+		valueAlloca, valueAllocaCast, valueAllocaSize = b.createTemporaryAlloca(valueType, "chan.value")
+	}
 
 	// Allocate blockedlist buffer.
 	channelBlockedList := b.mod.GetTypeByName("runtime.channelBlockedList")
@@ -64,9 +80,14 @@ func (b *builder) createChanRecv(unop *ssa.UnOp) llvm.Value {
 
 	// Do the receive.
 	commaOk := b.createRuntimeCall("chanRecv", []llvm.Value{ch, valueAllocaCast, channelBlockedListAlloca}, "")
-	received := b.CreateLoad(valueAlloca, "chan.received")
+	var received llvm.Value
+	if isZeroSize {
+		received = llvm.ConstNull(valueType)
+	} else {
+		received = b.CreateLoad(valueAlloca, "chan.received")
+		b.emitLifetimeEnd(valueAllocaCast, valueAllocaSize)
+	}
 	b.emitLifetimeEnd(channelBlockedListAllocaCast, channelBlockedListAllocaSize)
-	b.emitLifetimeEnd(valueAllocaCast, valueAllocaSize)
 
 	if unop.CommaOk {
 		tuple := llvm.Undef(b.ctx.StructType([]llvm.Type{valueType, b.ctx.Int1Type()}, false))
@@ -116,7 +137,6 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 	// determine the receive buffer size and alignment.
 	recvbufSize := uint64(0)
 	recvbufAlign := 0
-	hasReceives := false
 	var selectStates []llvm.Value
 	chanSelectStateType := b.getLLVMRuntimeType("chanSelectState")
 	for _, state := range expr.States {
@@ -133,7 +153,6 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 			if align := b.targetData.ABITypeAlignment(llvmType); align > recvbufAlign {
 				recvbufAlign = align
 			}
-			hasReceives = true
 		case types.SendOnly:
 			// Store this value in an alloca and put a pointer to this alloca
 			// in the send state.
@@ -150,7 +169,7 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 
 	// Create a receive buffer, where the received value will be stored.
 	recvbuf := llvm.Undef(b.i8ptrType)
-	if hasReceives {
+	if recvbufSize != 0 {
 		allocaType := llvm.ArrayType(b.ctx.Int8Type(), int(recvbufSize))
 		recvbufAlloca, _, _ := b.createTemporaryAlloca(allocaType, "select.recvbuf.alloca")
 		recvbufAlloca.SetAlignment(recvbufAlign)

compiler/compiler_go118.go

@@ -0,0 +1,18 @@
+//go:build go1.18
+// +build go1.18
+
+package compiler
+
+// Workaround for Go 1.17 support. Should be removed once we drop Go 1.17
+// support.
+
+import "go/types"
+
+func init() {
+	typeParamUnderlyingType = func(t types.Type) types.Type {
+		if t, ok := t.(*types.TypeParam); ok {
+			return t.Underlying()
+		}
+		return t
+	}
+}

compiler/compiler_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/goenv"
 	"github.com/tinygo-org/tinygo/loader"
 	"tinygo.org/x/go-llvm"
 )
@@ -16,58 +17,99 @@ import (
 // Pass -update to go test to update the output of the test files.
 var flagUpdate = flag.Bool("update", false, "update tests based on test output")
 
+type testCase struct {
+	file      string
+	target    string
+	scheduler string
+}
+
 // Basic tests for the compiler. Build some Go files and compare the output with
 // the expected LLVM IR for regression testing.
 func TestCompiler(t *testing.T) {
-	// Check LLVM version.
+	t.Parallel()
+
+	// Determine LLVM version.
 	llvmMajor, err := strconv.Atoi(strings.SplitN(llvm.Version, ".", 2)[0])
 	if err != nil {
 		t.Fatal("could not parse LLVM version:", llvm.Version)
 	}
-	if llvmMajor < 11 {
-		// It is likely this version needs to be bumped in the future.
-		// The goal is to at least test the LLVM version that's used by default
-		// in TinyGo and (if possible without too many workarounds) also some
-		// previous versions.
-		t.Skip("compiler tests require LLVM 11 or above, got LLVM ", llvm.Version)
-	}
 
-	target, err := compileopts.LoadTarget("i686--linux")
+	// Determine Go minor version (e.g. 16 in go1.16.3).
+	_, goMinor, err := goenv.GetGorootVersion(goenv.Get("GOROOT"))
 	if err != nil {
-		t.Fatal("failed to load target:", err)
-	}
-	config := &compileopts.Config{
-		Options: &compileopts.Options{},
-		Target:  target,
-	}
-	compilerConfig := &Config{
-		Triple:             config.Triple(),
-		GOOS:               config.GOOS(),
-		GOARCH:             config.GOARCH(),
-		CodeModel:          config.CodeModel(),
-		RelocationModel:    config.RelocationModel(),
-		Scheduler:          config.Scheduler(),
-		FuncImplementation: config.FuncImplementation(),
-		AutomaticStackSize: config.AutomaticStackSize(),
-	}
-	machine, err := NewTargetMachine(compilerConfig)
-	if err != nil {
-		t.Fatal("failed to create target machine:", err)
+		t.Fatal("could not read Go version:", err)
 	}
 
-	tests := []string{
-		"basic.go",
-		"pointer.go",
-		"slice.go",
-		"string.go",
-		"float.go",
-		"interface.go",
+	// Determine which tests to run, depending on the Go and LLVM versions.
+	tests := []testCase{
+		{"basic.go", "", ""},
+		{"pointer.go", "", ""},
+		{"slice.go", "", ""},
+		{"string.go", "", ""},
+		{"float.go", "", ""},
+		{"interface.go", "", ""},
+		{"func.go", "", ""},
+		{"pragma.go", "", ""},
+		{"goroutine.go", "wasm", "asyncify"},
+		{"goroutine.go", "cortex-m-qemu", "tasks"},
+		{"channel.go", "", ""},
+		{"intrinsics.go", "cortex-m-qemu", ""},
+		{"intrinsics.go", "wasm", ""},
+		{"gc.go", "", ""},
+	}
+	if llvmMajor >= 12 {
+		tests = append(tests, testCase{"intrinsics.go", "cortex-m-qemu", ""})
+		tests = append(tests, testCase{"intrinsics.go", "wasm", ""})
+	}
+	if goMinor >= 17 {
+		tests = append(tests, testCase{"go1.17.go", "", ""})
 	}
 
-	for _, testCase := range tests {
-		t.Run(testCase, func(t *testing.T) {
+	for _, tc := range tests {
+		name := tc.file
+		targetString := "wasm"
+		if tc.target != "" {
+			targetString = tc.target
+			name += "-" + tc.target
+		}
+		if tc.scheduler != "" {
+			name += "-" + tc.scheduler
+		}
+
+		t.Run(name, func(t *testing.T) {
+			options := &compileopts.Options{
+				Target: targetString,
+			}
+			target, err := compileopts.LoadTarget(options)
+			if err != nil {
+				t.Fatal("failed to load target:", err)
+			}
+			if tc.scheduler != "" {
+				options.Scheduler = tc.scheduler
+			}
+			config := &compileopts.Config{
+				Options: options,
+				Target:  target,
+			}
+			compilerConfig := &Config{
+				Triple:             config.Triple(),
+				GOOS:               config.GOOS(),
+				GOARCH:             config.GOARCH(),
+				CodeModel:          config.CodeModel(),
+				RelocationModel:    config.RelocationModel(),
+				Scheduler:          config.Scheduler(),
+				AutomaticStackSize: config.AutomaticStackSize(),
+				DefaultStackSize:   config.Target.DefaultStackSize,
+				NeedsStackObjects:  config.NeedsStackObjects(),
+			}
+			machine, err := NewTargetMachine(compilerConfig)
+			if err != nil {
+				t.Fatal("failed to create target machine:", err)
+			}
+			defer machine.Dispose()
+
 			// Load entire program AST into memory.
-			lprogram, err := loader.Load(config, []string{"./testdata/" + testCase}, config.ClangHeaders, types.Config{
+			lprogram, err := loader.Load(config, "./testdata/"+tc.file, config.ClangHeaders, types.Config{
 				Sizes: Sizes(machine),
 			})
 			if err != nil {
@@ -75,20 +117,25 @@ func TestCompiler(t *testing.T) {
 			}
 			err = lprogram.Parse()
 			if err != nil {
-				t.Fatalf("could not parse test case %s: %s", testCase, err)
+				t.Fatalf("could not parse test case %s: %s", tc.file, err)
 			}
 
 			// Compile AST to IR.
 			program := lprogram.LoadSSA()
 			pkg := lprogram.MainPkg()
-			mod, errs := CompilePackage(testCase, pkg, program.Package(pkg.Pkg), machine, compilerConfig, false)
+			mod, errs := CompilePackage(tc.file, pkg, program.Package(pkg.Pkg), machine, compilerConfig, false)
 			if errs != nil {
 				for _, err := range errs {
-					t.Log("error:", err)
+					t.Error(err)
 				}
 				return
 			}
 
+			err = llvm.VerifyModule(mod, llvm.PrintMessageAction)
+			if err != nil {
+				t.Error(err)
+			}
+
 			// Optimize IR a little.
 			funcPasses := llvm.NewFunctionPassManagerForModule(mod)
 			defer funcPasses.Dispose()
@@ -99,18 +146,25 @@ func TestCompiler(t *testing.T) {
 			}
 			funcPasses.FinalizeFunc()
 
-			outfile := "./testdata/" + testCase[:len(testCase)-3] + ".ll"
+			outFilePrefix := tc.file[:len(tc.file)-3]
+			if tc.target != "" {
+				outFilePrefix += "-" + tc.target
+			}
+			if tc.scheduler != "" {
+				outFilePrefix += "-" + tc.scheduler
+			}
+			outPath := "./testdata/" + outFilePrefix + ".ll"
 
 			// Update test if needed. Do not check the result.
 			if *flagUpdate {
-				err := ioutil.WriteFile(outfile, []byte(mod.String()), 0666)
+				err := ioutil.WriteFile(outPath, []byte(mod.String()), 0666)
 				if err != nil {
 					t.Error("failed to write updated output file:", err)
 				}
 				return
 			}
 
-			expected, err := ioutil.ReadFile(outfile)
+			expected, err := ioutil.ReadFile(outPath)
 			if err != nil {
 				t.Fatal("failed to read golden file:", err)
 			}
@@ -146,6 +200,12 @@ func fuzzyEqualIR(s1, s2 string) bool {
 // stripped out.
 func filterIrrelevantIRLines(lines []string) []string {
 	var out []string
+	llvmVersion, err := strconv.Atoi(strings.Split(llvm.Version, ".")[0])
+	if err != nil {
+		// Note: this should never happen and if it does, it will always happen
+		// for a particular build because llvm.Version is a constant.
+		panic(err)
+	}
 	for _, line := range lines {
 		line = strings.Split(line, ";")[0]    // strip out comments/info
 		line = strings.TrimRight(line, "\r ") // drop '\r' on Windows and remove trailing spaces from comments
@@ -155,6 +215,11 @@ func filterIrrelevantIRLines(lines []string) []string {
 		if strings.HasPrefix(line, "source_filename = ") {
 			continue
 		}
+		if llvmVersion < 14 && strings.HasPrefix(line, "target datalayout = ") {
+			// The datalayout string may vary betewen LLVM versions.
+			// Right now test outputs are for LLVM 14 and higher.
+			continue
+		}
 		out = append(out, line)
 	}
 	return out

compiler/defer.go

@@ -217,7 +217,8 @@ func (b *builder) createDefer(instr *ssa.Defer) {
 		// This may be hit a variable number of times, so use a heap allocation.
 		size := b.targetData.TypeAllocSize(deferFrameType)
 		sizeValue := llvm.ConstInt(b.uintptrType, size, false)
-		allocCall := b.createRuntimeCall("alloc", []llvm.Value{sizeValue}, "defer.alloc.call")
+		nilPtr := llvm.ConstNull(b.i8ptrType)
+		allocCall := b.createRuntimeCall("alloc", []llvm.Value{sizeValue, nilPtr}, "defer.alloc.call")
 		alloca = b.CreateBitCast(allocCall, llvm.PointerType(deferFrameType, 0), "defer.alloc")
 	}
 	if b.NeedsStackObjects {
@@ -331,10 +332,10 @@ func (b *builder) createRunDefers() {
 				//Pass context
 				forwardParams = append(forwardParams, context)
 			} else {
-				// Isolate the typecode.
-				typecode := forwardParams[0]
-				forwardParams = forwardParams[1:]
-				fnPtr = b.getInvokePtr(callback, typecode)
+				// Move typecode from the start to the end of the list of
+				// parameters.
+				forwardParams = append(forwardParams[1:], forwardParams[0])
+				fnPtr = b.getInvokeFunction(callback)
 
 				// Add the context parameter. An interface call cannot also be a
 				// closure but we have to supply the parameter anyway for platforms
@@ -342,9 +343,6 @@ func (b *builder) createRunDefers() {
 				forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
 			}
 
-			// Parent coroutine handle.
-			forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
-
 			b.createCall(fnPtr, forwardParams, "")
 
 		case *ssa.Function:
@@ -373,9 +371,6 @@ func (b *builder) createRunDefers() {
 				// Add the context parameter. We know it is ignored by the receiving
 				// function, but we have to pass one anyway.
 				forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
-
-				// Parent coroutine handle.
-				forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
 			}
 
 			// Call real function.
@@ -402,9 +397,6 @@ func (b *builder) createRunDefers() {
 				forwardParams = append(forwardParams, forwardParam)
 			}
 
-			// Parent coroutine handle.
-			forwardParams = append(forwardParams, llvm.Undef(b.i8ptrType))
-
 			// Call deferred function.
 			b.createCall(b.getFunction(fn), forwardParams, "")
 		case *ssa.Builtin:

compiler/errors.go

@@ -3,7 +3,6 @@ package compiler
 // This file contains some utility functions related to error handling.
 
 import (
-	"go/scanner"
 	"go/token"
 	"go/types"
 	"path/filepath"
@@ -20,20 +19,11 @@ func (c *compilerContext) makeError(pos token.Pos, msg string) types.Error {
 	}
 }
 
+// addError adds a new compiler diagnostic with the given location and message.
 func (c *compilerContext) addError(pos token.Pos, msg string) {
 	c.diagnostics = append(c.diagnostics, c.makeError(pos, msg))
 }
 
-// errorAt returns an error value at the location of the instruction.
-// The location information may not be complete as it depends on debug
-// information in the IR.
-func errorAt(inst llvm.Value, msg string) scanner.Error {
-	return scanner.Error{
-		Pos: getPosition(inst),
-		Msg: msg,
-	}
-}
-
 // getPosition returns the position information for the given value, as far as
 // it is available.
 func getPosition(val llvm.Value) token.Position {

compiler/func.go

@@ -19,30 +19,8 @@ func (b *builder) createFuncValue(funcPtr, context llvm.Value, sig *types.Signat
 // createFuncValue creates a function value from a raw function pointer with no
 // context.
 func (c *compilerContext) createFuncValue(builder llvm.Builder, funcPtr, context llvm.Value, sig *types.Signature) llvm.Value {
-	var funcValueScalar llvm.Value
-	switch c.FuncImplementation {
-	case "doubleword":
-		// Closure is: {context, function pointer}
-		funcValueScalar = funcPtr
-	case "switch":
-		sigGlobal := c.getTypeCode(sig)
-		funcValueWithSignatureGlobalName := funcPtr.Name() + "$withSignature"
-		funcValueWithSignatureGlobal := c.mod.NamedGlobal(funcValueWithSignatureGlobalName)
-		if funcValueWithSignatureGlobal.IsNil() {
-			funcValueWithSignatureType := c.getLLVMRuntimeType("funcValueWithSignature")
-			funcValueWithSignature := llvm.ConstNamedStruct(funcValueWithSignatureType, []llvm.Value{
-				llvm.ConstPtrToInt(funcPtr, c.uintptrType),
-				sigGlobal,
-			})
-			funcValueWithSignatureGlobal = llvm.AddGlobal(c.mod, funcValueWithSignatureType, funcValueWithSignatureGlobalName)
-			funcValueWithSignatureGlobal.SetInitializer(funcValueWithSignature)
-			funcValueWithSignatureGlobal.SetGlobalConstant(true)
-			funcValueWithSignatureGlobal.SetLinkage(llvm.LinkOnceODRLinkage)
-		}
-		funcValueScalar = llvm.ConstPtrToInt(funcValueWithSignatureGlobal, c.uintptrType)
-	default:
-		panic("unimplemented func value variant")
-	}
+	// Closure is: {context, function pointer}
+	funcValueScalar := llvm.ConstBitCast(funcPtr, c.rawVoidFuncType)
 	funcValueType := c.getFuncType(sig)
 	funcValue := llvm.Undef(funcValueType)
 	funcValue = builder.CreateInsertValue(funcValue, context, 0, "")
@@ -50,6 +28,19 @@ func (c *compilerContext) createFuncValue(builder llvm.Builder, funcPtr, context
 	return funcValue
 }
 
+// getFuncSignatureID returns a new external global for a given signature. This
+// global reference is not real, it is only used during func lowering to assign
+// signature types to functions and will then be removed.
+func (c *compilerContext) getFuncSignatureID(sig *types.Signature) llvm.Value {
+	sigGlobalName := "reflect/types.funcid:" + getTypeCodeName(sig)
+	sigGlobal := c.mod.NamedGlobal(sigGlobalName)
+	if sigGlobal.IsNil() {
+		sigGlobal = llvm.AddGlobal(c.mod, c.ctx.Int8Type(), sigGlobalName)
+		sigGlobal.SetGlobalConstant(true)
+	}
+	return sigGlobal
+}
+
 // extractFuncScalar returns some scalar that can be used in comparisons. It is
 // a cheap operation.
 func (b *builder) extractFuncScalar(funcValue llvm.Value) llvm.Value {
@@ -66,31 +57,19 @@ func (b *builder) extractFuncContext(funcValue llvm.Value) llvm.Value {
 // value. This may be an expensive operation.
 func (b *builder) decodeFuncValue(funcValue llvm.Value, sig *types.Signature) (funcPtr, context llvm.Value) {
 	context = b.CreateExtractValue(funcValue, 0, "")
-	switch b.FuncImplementation {
-	case "doubleword":
-		funcPtr = b.CreateExtractValue(funcValue, 1, "")
-	case "switch":
-		llvmSig := b.getRawFuncType(sig)
-		sigGlobal := b.getTypeCode(sig)
-		funcPtr = b.createRuntimeCall("getFuncPtr", []llvm.Value{funcValue, sigGlobal}, "")
-		funcPtr = b.CreateIntToPtr(funcPtr, llvmSig, "")
-	default:
-		panic("unimplemented func value variant")
+	bitcast := b.CreateExtractValue(funcValue, 1, "")
+	if !bitcast.IsAConstantExpr().IsNil() && bitcast.Opcode() == llvm.BitCast {
+		funcPtr = bitcast.Operand(0)
+		return
 	}
+	llvmSig := b.getRawFuncType(sig)
+	funcPtr = b.CreateBitCast(bitcast, llvmSig, "")
 	return
 }
 
 // getFuncType returns the type of a func value given a signature.
 func (c *compilerContext) getFuncType(typ *types.Signature) llvm.Type {
-	switch c.FuncImplementation {
-	case "doubleword":
-		rawPtr := c.getRawFuncType(typ)
-		return c.ctx.StructType([]llvm.Type{c.i8ptrType, rawPtr}, false)
-	case "switch":
-		return c.getLLVMRuntimeType("funcValue")
-	default:
-		panic("unimplemented func value variant")
-	}
+	return c.ctx.StructType([]llvm.Type{c.i8ptrType, c.rawVoidFuncType}, false)
 }
 
 // getRawFuncType returns a LLVM function pointer type for a given signature.
@@ -136,7 +115,6 @@ func (c *compilerContext) getRawFuncType(typ *types.Signature) llvm.Type {
 	}
 	// All functions take these parameters at the end.
 	paramTypes = append(paramTypes, c.i8ptrType) // context
-	paramTypes = append(paramTypes, c.i8ptrType) // parent coroutine
 
 	// Make a func type out of the signature.
 	return llvm.PointerType(llvm.FunctionType(returnType, paramTypes, false), c.funcPtrAddrSpace)

compiler/goroutine.go

@@ -5,48 +5,116 @@ package compiler
 
 import (
 	"go/token"
+	"go/types"
 
 	"github.com/tinygo-org/tinygo/compiler/llvmutil"
 	"golang.org/x/tools/go/ssa"
 	"tinygo.org/x/go-llvm"
 )
 
-// createGoInstruction starts a new goroutine with the provided function pointer
-// and parameters.
-// In general, you should pass all regular parameters plus the context parameter.
-// There is one exception: the task-based scheduler needs to have the function
-// pointer passed in as a parameter too in addition to the context.
-//
-// Because a go statement doesn't return anything, return undef.
-func (b *builder) createGoInstruction(funcPtr llvm.Value, params []llvm.Value, prefix string, pos token.Pos) llvm.Value {
-	paramBundle := b.emitPointerPack(params)
-	var callee, stackSize llvm.Value
-	switch b.Scheduler {
-	case "none", "tasks":
-		callee = b.createGoroutineStartWrapper(funcPtr, prefix, pos)
-		if b.AutomaticStackSize {
-			// The stack size is not known until after linking. Call a dummy
-			// function that will be replaced with a load from a special ELF
-			// section that contains the stack size (and is modified after
-			// linking).
-			stackSizeFn := b.getFunction(b.program.ImportedPackage("internal/task").Members["getGoroutineStackSize"].(*ssa.Function))
-			stackSize = b.createCall(stackSizeFn, []llvm.Value{callee, llvm.Undef(b.i8ptrType), llvm.Undef(b.i8ptrType)}, "stacksize")
-		} else {
-			// The stack size is fixed at compile time. By emitting it here as a
-			// constant, it can be optimized.
-			stackSize = llvm.ConstInt(b.uintptrType, b.DefaultStackSize, false)
+// createGo emits code to start a new goroutine.
+func (b *builder) createGo(instr *ssa.Go) {
+	// Get all function parameters to pass to the goroutine.
+	var params []llvm.Value
+	for _, param := range instr.Call.Args {
+		params = append(params, b.getValue(param))
+	}
+
+	var prefix string
+	var funcPtr llvm.Value
+	hasContext := false
+	if callee := instr.Call.StaticCallee(); callee != nil {
+		// Static callee is known. This makes it easier to start a new
+		// goroutine.
+		var context llvm.Value
+		switch value := instr.Call.Value.(type) {
+		case *ssa.Function:
+			// Goroutine call is regular function call. No context is necessary.
+		case *ssa.MakeClosure:
+			// A goroutine call on a func value, but the callee is trivial to find. For
+			// example: immediately applied functions.
+			funcValue := b.getValue(value)
+			context = b.extractFuncContext(funcValue)
+		default:
+			panic("StaticCallee returned an unexpected value")
 		}
-	case "coroutines":
-		callee = b.CreatePtrToInt(funcPtr, b.uintptrType, "")
-		// There is no goroutine stack size: coroutines are used instead of
-		// stacks.
-		stackSize = llvm.Undef(b.uintptrType)
-	default:
-		panic("unreachable")
+		if !context.IsNil() {
+			params = append(params, context) // context parameter
+			hasContext = true
+		}
+		funcPtr = b.getFunction(callee)
+	} else if builtin, ok := instr.Call.Value.(*ssa.Builtin); ok {
+		// We cheat. None of the builtins do any long or blocking operation, so
+		// we might as well run these builtins right away without the program
+		// noticing the difference.
+		// Possible exceptions:
+		//   - copy: this is a possibly long operation, but not a blocking
+		//     operation. Semantically it makes no difference to run it right
+		//     away (not in a goroutine). However, in practice it makes no sense
+		//     to run copy in a goroutine as there is no way to (safely) know
+		//     when it is finished.
+		//   - panic: the error message would appear in the parent goroutine.
+		//     But because `go panic("err")` would halt the program anyway
+		//     (there is no recover), panicking right away would give the same
+		//     behavior as creating a goroutine, switching the scheduler to that
+		//     goroutine, and panicking there. So this optimization seems
+		//     correct.
+		//   - recover: because it runs in a new goroutine, it is never a
+		//     deferred function. Thus this is a no-op.
+		if builtin.Name() == "recover" {
+			// This is a no-op, even in a deferred function:
+			//   go recover()
+			return
+		}
+		var argTypes []types.Type
+		var argValues []llvm.Value
+		for _, arg := range instr.Call.Args {
+			argTypes = append(argTypes, arg.Type())
+			argValues = append(argValues, b.getValue(arg))
+		}
+		b.createBuiltin(argTypes, argValues, builtin.Name(), instr.Pos())
+		return
+	} else if instr.Call.IsInvoke() {
+		// This is a method call on an interface value.
+		itf := b.getValue(instr.Call.Value)
+		itfTypeCode := b.CreateExtractValue(itf, 0, "")
+		itfValue := b.CreateExtractValue(itf, 1, "")
+		funcPtr = b.getInvokeFunction(&instr.Call)
+		params = append([]llvm.Value{itfValue}, params...) // start with receiver
+		params = append(params, itfTypeCode)               // end with typecode
+	} else {
+		// This is a function pointer.
+		// At the moment, two extra params are passed to the newly started
+		// goroutine:
+		//   * The function context, for closures.
+		//   * The function pointer (for tasks).
+		var context llvm.Value
+		funcPtr, context = b.decodeFuncValue(b.getValue(instr.Call.Value), instr.Call.Value.Type().Underlying().(*types.Signature))
+		params = append(params, context, funcPtr)
+		hasContext = true
+		prefix = b.fn.RelString(nil)
+	}
+
+	paramBundle := b.emitPointerPack(params)
+	var stackSize llvm.Value
+	callee := b.createGoroutineStartWrapper(funcPtr, prefix, hasContext, instr.Pos())
+	if b.AutomaticStackSize {
+		// The stack size is not known until after linking. Call a dummy
+		// function that will be replaced with a load from a special ELF
+		// section that contains the stack size (and is modified after
+		// linking).
+		stackSizeFn := b.getFunction(b.program.ImportedPackage("internal/task").Members["getGoroutineStackSize"].(*ssa.Function))
+		stackSize = b.createCall(stackSizeFn, []llvm.Value{callee, llvm.Undef(b.i8ptrType)}, "stacksize")
+	} else {
+		// The stack size is fixed at compile time. By emitting it here as a
+		// constant, it can be optimized.
+		if (b.Scheduler == "tasks" || b.Scheduler == "asyncify") && b.DefaultStackSize == 0 {
+			b.addError(instr.Pos(), "default stack size for goroutines is not set")
+		}
+		stackSize = llvm.ConstInt(b.uintptrType, b.DefaultStackSize, false)
 	}
 	start := b.getFunction(b.program.ImportedPackage("internal/task").Members["start"].(*ssa.Function))
-	b.createCall(start, []llvm.Value{callee, paramBundle, stackSize, llvm.Undef(b.i8ptrType), llvm.ConstPointerNull(b.i8ptrType)}, "")
-	return llvm.Undef(funcPtr.Type().ElementType().ReturnType())
+	b.createCall(start, []llvm.Value{callee, paramBundle, stackSize, llvm.Undef(b.i8ptrType)}, "")
 }
 
 // createGoroutineStartWrapper creates a wrapper for the task-based
@@ -67,12 +135,22 @@ func (b *builder) createGoInstruction(funcPtr llvm.Value, params []llvm.Value, p
 // allows a single (pointer) argument to the newly started goroutine. Also, it
 // ignores the return value because newly started goroutines do not have a
 // return value.
-func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix string, pos token.Pos) llvm.Value {
+//
+// The hasContext parameter indicates whether the context parameter (the second
+// to last parameter of the function) is used for this wrapper. If hasContext is
+// false, the parameter bundle is assumed to have no context parameter and undef
+// is passed instead.
+func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix string, hasContext bool, pos token.Pos) llvm.Value {
 	var wrapper llvm.Value
 
 	builder := c.ctx.NewBuilder()
 	defer builder.Dispose()
 
+	var deadlock llvm.Value
+	if c.Scheduler == "asyncify" {
+		deadlock = c.getFunction(c.program.ImportedPackage("runtime").Members["deadlock"].(*ssa.Function))
+	}
+
 	if !fn.IsAFunction().IsNil() {
 		// See whether this wrapper has already been created. If so, return it.
 		name := fn.Name()
@@ -84,6 +162,7 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 		// Create the wrapper.
 		wrapperType := llvm.FunctionType(c.ctx.VoidType(), []llvm.Type{c.i8ptrType}, false)
 		wrapper = llvm.AddFunction(c.mod, name+"$gowrapper", wrapperType)
+		c.addStandardAttributes(wrapper)
 		wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
 		wrapper.SetUnnamedAddr(true)
 		wrapper.AddAttributeAtIndex(-1, c.ctx.CreateStringAttribute("tinygo-gowrapper", name))
@@ -114,12 +193,23 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 
 		// Create the list of params for the call.
 		paramTypes := fn.Type().ElementType().ParamTypes()
-		params := llvmutil.EmitPointerUnpack(builder, c.mod, wrapper.Param(0), paramTypes[:len(paramTypes)-1])
-		params = append(params, llvm.Undef(c.i8ptrType))
+		if !hasContext {
+			paramTypes = paramTypes[:len(paramTypes)-1] // strip context parameter
+		}
+		params := llvmutil.EmitPointerUnpack(builder, c.mod, wrapper.Param(0), paramTypes)
+		if !hasContext {
+			params = append(params, llvm.Undef(c.i8ptrType)) // add dummy context parameter
+		}
 
 		// Create the call.
 		builder.CreateCall(fn, params, "")
 
+		if c.Scheduler == "asyncify" {
+			builder.CreateCall(deadlock, []llvm.Value{
+				llvm.Undef(c.i8ptrType),
+			}, "")
+		}
+
 	} else {
 		// For a function pointer like this:
 		//
@@ -141,6 +231,7 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 		// Create the wrapper.
 		wrapperType := llvm.FunctionType(c.ctx.VoidType(), []llvm.Type{c.i8ptrType}, false)
 		wrapper = llvm.AddFunction(c.mod, prefix+".gowrapper", wrapperType)
+		c.addStandardAttributes(wrapper)
 		wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
 		wrapper.SetUnnamedAddr(true)
 		wrapper.AddAttributeAtIndex(-1, c.ctx.CreateStringAttribute("tinygo-gowrapper", ""))
@@ -171,23 +262,31 @@ func (c *compilerContext) createGoroutineStartWrapper(fn llvm.Value, prefix stri
 
 		// Get the list of parameters, with the extra parameters at the end.
 		paramTypes := fn.Type().ElementType().ParamTypes()
-		paramTypes[len(paramTypes)-1] = fn.Type() // the last element is the function pointer
+		paramTypes = append(paramTypes, fn.Type()) // the last element is the function pointer
 		params := llvmutil.EmitPointerUnpack(builder, c.mod, wrapper.Param(0), paramTypes)
 
 		// Get the function pointer.
 		fnPtr := params[len(params)-1]
-
-		// Ignore the last param, which isn't used anymore.
-		// TODO: avoid this extra "parent handle" parameter in most functions.
-		params[len(params)-1] = llvm.Undef(c.i8ptrType)
+		params = params[:len(params)-1]
 
 		// Create the call.
 		builder.CreateCall(fnPtr, params, "")
+
+		if c.Scheduler == "asyncify" {
+			builder.CreateCall(deadlock, []llvm.Value{
+				llvm.Undef(c.i8ptrType),
+			}, "")
+		}
 	}
 
-	// Finish the function. Every basic block must end in a terminator, and
-	// because goroutines never return a value we can simply return void.
-	builder.CreateRetVoid()
+	if c.Scheduler == "asyncify" {
+		// The goroutine was terminated via deadlock.
+		builder.CreateUnreachable()
+	} else {
+		// Finish the function. Every basic block must end in a terminator, and
+		// because goroutines never return a value we can simply return void.
+		builder.CreateRetVoid()
+	}
 
 	// Return a ptrtoint of the wrapper, not the function itself.
 	return builder.CreatePtrToInt(wrapper, c.uintptrType, "")

compiler/inlineasm.go

@@ -24,7 +24,7 @@ func (b *builder) createInlineAsm(args []ssa.Value) (llvm.Value, error) {
 	// Magic function: insert inline assembly instead of calling it.
 	fnType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{}, false)
 	asm := constant.StringVal(args[0].(*ssa.Const).Value)
-	target := llvm.InlineAsm(fnType, asm, "", true, false, 0)
+	target := llvm.InlineAsm(fnType, asm, "", true, false, 0, false)
 	return b.CreateCall(target, nil, ""), nil
 }
 
@@ -72,7 +72,7 @@ func (b *builder) createInlineAsmFull(instr *ssa.CallCommon) (llvm.Value, error)
 	args := []llvm.Value{}
 	constraints := []string{}
 	hasOutput := false
-	asmString = regexp.MustCompile("\\{\\}").ReplaceAllStringFunc(asmString, func(s string) string {
+	asmString = regexp.MustCompile(`\{\}`).ReplaceAllStringFunc(asmString, func(s string) string {
 		hasOutput = true
 		return "$0"
 	})
@@ -80,7 +80,7 @@ func (b *builder) createInlineAsmFull(instr *ssa.CallCommon) (llvm.Value, error)
 		constraints = append(constraints, "=&r")
 		registerNumbers[""] = 0
 	}
-	asmString = regexp.MustCompile("\\{[a-zA-Z]+\\}").ReplaceAllStringFunc(asmString, func(s string) string {
+	asmString = regexp.MustCompile(`\{[a-zA-Z]+\}`).ReplaceAllStringFunc(asmString, func(s string) string {
 		// TODO: skip strings like {r4} etc. that look like ARM push/pop
 		// instructions.
 		name := s[1 : len(s)-1]
@@ -98,7 +98,10 @@ func (b *builder) createInlineAsmFull(instr *ssa.CallCommon) (llvm.Value, error)
 			case llvm.IntegerTypeKind:
 				constraints = append(constraints, "r")
 			case llvm.PointerTypeKind:
-				constraints = append(constraints, "*m")
+				// Memory references require a type in LLVM 14, probably as a
+				// preparation for opaque pointers.
+				err = b.makeError(instr.Pos(), "support for pointer operands was dropped in TinyGo 0.23")
+				return s
 			default:
 				err = b.makeError(instr.Pos(), "unknown type in inline assembly for value: "+name)
 				return s
@@ -116,7 +119,7 @@ func (b *builder) createInlineAsmFull(instr *ssa.CallCommon) (llvm.Value, error)
 		outputType = b.ctx.VoidType()
 	}
 	fnType := llvm.FunctionType(outputType, argTypes, false)
-	target := llvm.InlineAsm(fnType, asmString, strings.Join(constraints, ","), true, false, 0)
+	target := llvm.InlineAsm(fnType, asmString, strings.Join(constraints, ","), true, false, 0, false)
 	result := b.CreateCall(target, args, "")
 	if hasOutput {
 		return result, nil
@@ -159,7 +162,7 @@ func (b *builder) emitSVCall(args []ssa.Value) (llvm.Value, error) {
 	// marked as clobbered.
 	constraints += ",~{r1},~{r2},~{r3}"
 	fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-	target := llvm.InlineAsm(fnType, asm, constraints, true, false, 0)
+	target := llvm.InlineAsm(fnType, asm, constraints, true, false, 0, false)
 	return b.CreateCall(target, llvmArgs, ""), nil
 }
 
@@ -197,7 +200,7 @@ func (b *builder) emitSV64Call(args []ssa.Value) (llvm.Value, error) {
 	// marked as clobbered.
 	constraints += ",~{x1},~{x2},~{x3},~{x4},~{x5},~{x6},~{x7}"
 	fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-	target := llvm.InlineAsm(fnType, asm, constraints, true, false, 0)
+	target := llvm.InlineAsm(fnType, asm, constraints, true, false, 0, false)
 	return b.CreateCall(target, llvmArgs, ""), nil
 }
 
@@ -222,24 +225,24 @@ func (b *builder) emitCSROperation(call *ssa.CallCommon) (llvm.Value, error) {
 		// marked as such.
 		fnType := llvm.FunctionType(b.uintptrType, nil, false)
 		asm := fmt.Sprintf("csrr $0, %d", csr)
-		target := llvm.InlineAsm(fnType, asm, "=r", true, false, 0)
+		target := llvm.InlineAsm(fnType, asm, "=r", true, false, 0, false)
 		return b.CreateCall(target, nil, ""), nil
 	case "Set":
 		fnType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{b.uintptrType}, false)
 		asm := fmt.Sprintf("csrw %d, $0", csr)
-		target := llvm.InlineAsm(fnType, asm, "r", true, false, 0)
+		target := llvm.InlineAsm(fnType, asm, "r", true, false, 0, false)
 		return b.CreateCall(target, []llvm.Value{b.getValue(call.Args[1])}, ""), nil
 	case "SetBits":
 		// Note: it may be possible to optimize this to csrrsi in many cases.
 		fnType := llvm.FunctionType(b.uintptrType, []llvm.Type{b.uintptrType}, false)
 		asm := fmt.Sprintf("csrrs $0, %d, $1", csr)
-		target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0)
+		target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0, false)
 		return b.CreateCall(target, []llvm.Value{b.getValue(call.Args[1])}, ""), nil
 	case "ClearBits":
 		// Note: it may be possible to optimize this to csrrci in many cases.
 		fnType := llvm.FunctionType(b.uintptrType, []llvm.Type{b.uintptrType}, false)
 		asm := fmt.Sprintf("csrrc $0, %d, $1", csr)
-		target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0)
+		target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0, false)
 		return b.CreateCall(target, []llvm.Value{b.getValue(call.Args[1])}, ""), nil
 	default:
 		return llvm.Value{}, b.makeError(call.Pos(), "unknown CSR operation: "+name)

compiler/interface.go

@@ -31,6 +31,15 @@ func (b *builder) createMakeInterface(val llvm.Value, typ types.Type, pos token.
 	return itf
 }
 
+// extractValueFromInterface extract the value from an interface value
+// (runtime._interface) under the assumption that it is of the type given in
+// llvmType. The behavior is undefied if the interface is nil or llvmType
+// doesn't match the underlying type of the interface.
+func (b *builder) extractValueFromInterface(itf llvm.Value, llvmType llvm.Type) llvm.Value {
+	valuePtr := b.CreateExtractValue(itf, 1, "typeassert.value.ptr")
+	return b.emitPointerUnpack(valuePtr, []llvm.Type{llvmType})[0]
+}
+
 // getTypeCode returns a reference to a type code.
 // It returns a pointer to an external global which should be replaced with the
 // real type in the interface lowering pass.
@@ -46,6 +55,8 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 		var references llvm.Value
 		var length int64
 		var methodSet llvm.Value
+		var ptrTo llvm.Value
+		var typeAssert llvm.Value
 		switch typ := typ.(type) {
 		case *types.Named:
 			references = c.getTypeCode(typ.Underlying())
@@ -68,23 +79,32 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 		}
 		if _, ok := typ.Underlying().(*types.Interface); !ok {
 			methodSet = c.getTypeMethodSet(typ)
+		} else {
+			typeAssert = c.getInterfaceImplementsFunc(typ)
+			typeAssert = llvm.ConstPtrToInt(typeAssert, c.uintptrType)
 		}
-		if !references.IsNil() || length != 0 || !methodSet.IsNil() {
-			// Set the 'references' field of the runtime.typecodeID struct.
-			globalValue := llvm.ConstNull(global.Type().ElementType())
-			if !references.IsNil() {
-				globalValue = llvm.ConstInsertValue(globalValue, references, []uint32{0})
-			}
-			if length != 0 {
-				lengthValue := llvm.ConstInt(c.uintptrType, uint64(length), false)
-				globalValue = llvm.ConstInsertValue(globalValue, lengthValue, []uint32{1})
-			}
-			if !methodSet.IsNil() {
-				globalValue = llvm.ConstInsertValue(globalValue, methodSet, []uint32{2})
-			}
-			global.SetInitializer(globalValue)
-			global.SetLinkage(llvm.LinkOnceODRLinkage)
+		if _, ok := typ.Underlying().(*types.Pointer); !ok {
+			ptrTo = c.getTypeCode(types.NewPointer(typ))
 		}
+		globalValue := llvm.ConstNull(global.Type().ElementType())
+		if !references.IsNil() {
+			globalValue = llvm.ConstInsertValue(globalValue, references, []uint32{0})
+		}
+		if length != 0 {
+			lengthValue := llvm.ConstInt(c.uintptrType, uint64(length), false)
+			globalValue = llvm.ConstInsertValue(globalValue, lengthValue, []uint32{1})
+		}
+		if !methodSet.IsNil() {
+			globalValue = llvm.ConstInsertValue(globalValue, methodSet, []uint32{2})
+		}
+		if !ptrTo.IsNil() {
+			globalValue = llvm.ConstInsertValue(globalValue, ptrTo, []uint32{3})
+		}
+		if !typeAssert.IsNil() {
+			globalValue = llvm.ConstInsertValue(globalValue, typeAssert, []uint32{4})
+		}
+		global.SetInitializer(globalValue)
+		global.SetLinkage(llvm.LinkOnceODRLinkage)
 		global.SetGlobalConstant(true)
 	}
 	return global
@@ -132,6 +152,27 @@ func (c *compilerContext) makeStructTypeFields(typ *types.Struct) llvm.Value {
 	return structGlobal
 }
 
+var basicTypes = [...]string{
+	types.Bool:          "bool",
+	types.Int:           "int",
+	types.Int8:          "int8",
+	types.Int16:         "int16",
+	types.Int32:         "int32",
+	types.Int64:         "int64",
+	types.Uint:          "uint",
+	types.Uint8:         "uint8",
+	types.Uint16:        "uint16",
+	types.Uint32:        "uint32",
+	types.Uint64:        "uint64",
+	types.Uintptr:       "uintptr",
+	types.Float32:       "float32",
+	types.Float64:       "float64",
+	types.Complex64:     "complex64",
+	types.Complex128:    "complex128",
+	types.String:        "string",
+	types.UnsafePointer: "unsafe.Pointer",
+}
+
 // getTypeCodeName returns a name for this type that can be used in the
 // interface lowering pass to assign type codes as expected by the reflect
 // package. See getTypeCodeNum.
@@ -142,54 +183,17 @@ func getTypeCodeName(t types.Type) string {
 	case *types.Array:
 		return "array:" + strconv.FormatInt(t.Len(), 10) + ":" + getTypeCodeName(t.Elem())
 	case *types.Basic:
-		var kind string
-		switch t.Kind() {
-		case types.Bool:
-			kind = "bool"
-		case types.Int:
-			kind = "int"
-		case types.Int8:
-			kind = "int8"
-		case types.Int16:
-			kind = "int16"
-		case types.Int32:
-			kind = "int32"
-		case types.Int64:
-			kind = "int64"
-		case types.Uint:
-			kind = "uint"
-		case types.Uint8:
-			kind = "uint8"
-		case types.Uint16:
-			kind = "uint16"
-		case types.Uint32:
-			kind = "uint32"
-		case types.Uint64:
-			kind = "uint64"
-		case types.Uintptr:
-			kind = "uintptr"
-		case types.Float32:
-			kind = "float32"
-		case types.Float64:
-			kind = "float64"
-		case types.Complex64:
-			kind = "complex64"
-		case types.Complex128:
-			kind = "complex128"
-		case types.String:
-			kind = "string"
-		case types.UnsafePointer:
-			kind = "unsafeptr"
-		default:
-			panic("unknown basic type: " + t.Name())
-		}
-		return "basic:" + kind
+		return "basic:" + basicTypes[t.Kind()]
 	case *types.Chan:
 		return "chan:" + getTypeCodeName(t.Elem())
 	case *types.Interface:
 		methods := make([]string, t.NumMethods())
 		for i := 0; i < t.NumMethods(); i++ {
-			methods[i] = t.Method(i).Name() + ":" + getTypeCodeName(t.Method(i).Type())
+			name := t.Method(i).Name()
+			if !token.IsExported(name) {
+				name = t.Method(i).Pkg().Path() + "." + name
+			}
+			methods[i] = name + ":" + getTypeCodeName(t.Method(i).Type())
 		}
 		return "interface:" + "{" + strings.Join(methods, ",") + "}"
 	case *types.Map:
@@ -302,15 +306,33 @@ func (c *compilerContext) getInterfaceMethodSet(typ types.Type) llvm.Value {
 	return llvm.ConstGEP(global, []llvm.Value{zero, zero})
 }
 
+// getMethodSignatureName returns a unique name (that can be used as the name of
+// a global) for the given method.
+func (c *compilerContext) getMethodSignatureName(method *types.Func) string {
+	signature := methodSignature(method)
+	var globalName string
+	if token.IsExported(method.Name()) {
+		globalName = "reflect/methods." + signature
+	} else {
+		globalName = method.Type().(*types.Signature).Recv().Pkg().Path() + ".$methods." + signature
+	}
+	return globalName
+}
+
 // getMethodSignature returns a global variable which is a reference to an
 // external *i8 indicating the indicating the signature of this method. It is
 // used during the interface lowering pass.
 func (c *compilerContext) getMethodSignature(method *types.Func) llvm.Value {
-	signature := methodSignature(method)
-	signatureGlobal := c.mod.NamedGlobal("func " + signature)
+	globalName := c.getMethodSignatureName(method)
+	signatureGlobal := c.mod.NamedGlobal(globalName)
 	if signatureGlobal.IsNil() {
-		signatureGlobal = llvm.AddGlobal(c.mod, c.ctx.Int8Type(), "func "+signature)
+		// TODO: put something useful in these globals, such as the method
+		// signature. Useful to one day implement reflect.Value.Method(n).
+		signatureGlobal = llvm.AddGlobal(c.mod, c.ctx.Int8Type(), globalName)
+		signatureGlobal.SetInitializer(llvm.ConstInt(c.ctx.Int8Type(), 0, false))
+		signatureGlobal.SetLinkage(llvm.LinkOnceODRLinkage)
 		signatureGlobal.SetGlobalConstant(true)
+		signatureGlobal.SetAlignment(1)
 	}
 	return signatureGlobal
 }
@@ -330,18 +352,19 @@ func (b *builder) createTypeAssert(expr *ssa.TypeAssert) llvm.Value {
 	commaOk := llvm.Value{}
 	if _, ok := expr.AssertedType.Underlying().(*types.Interface); ok {
 		// Type assert on interface type.
-		// This pseudo call will be lowered in the interface lowering pass to a
-		// real call which checks whether the provided typecode is any of the
-		// concrete types that implements this interface.
+		// This is a call to an interface type assert function.
+		// The interface lowering pass will define this function by filling it
+		// with a type switch over all concrete types that implement this
+		// interface, and returning whether it's one of the matched types.
 		// This is very different from how interface asserts are implemented in
 		// the main Go compiler, where the runtime checks whether the type
 		// implements each method of the interface. See:
 		// https://research.swtch.com/interfaces
-		methodSet := b.getInterfaceMethodSet(expr.AssertedType)
-		commaOk = b.createRuntimeCall("interfaceImplements", []llvm.Value{actualTypeNum, methodSet}, "")
+		fn := b.getInterfaceImplementsFunc(expr.AssertedType)
+		commaOk = b.CreateCall(fn, []llvm.Value{actualTypeNum}, "")
 
 	} else {
-		globalName := "reflect/types.type:" + getTypeCodeName(expr.AssertedType) + "$id"
+		globalName := "reflect/types.typeid:" + getTypeCodeName(expr.AssertedType)
 		assertedTypeCodeGlobal := b.mod.NamedGlobal(globalName)
 		if assertedTypeCodeGlobal.IsNil() {
 			// Create a new typecode global.
@@ -382,8 +405,7 @@ func (b *builder) createTypeAssert(expr *ssa.TypeAssert) llvm.Value {
 	} else {
 		// Type assert on concrete type. Extract the underlying type from
 		// the interface (but only after checking it matches).
-		valuePtr := b.CreateExtractValue(itf, 1, "typeassert.value.ptr")
-		valueOk = b.emitPointerUnpack(valuePtr, []llvm.Type{assertedType})[0]
+		valueOk = b.extractValueFromInterface(itf, assertedType)
 	}
 	b.CreateBr(nextBlock)
 
@@ -405,39 +427,52 @@ func (b *builder) createTypeAssert(expr *ssa.TypeAssert) llvm.Value {
 	}
 }
 
-// getInvokePtr creates an interface function pointer lookup for the specified invoke instruction, using a specified typecode.
-func (b *builder) getInvokePtr(instr *ssa.CallCommon, typecode llvm.Value) llvm.Value {
-	llvmFnType := b.getRawFuncType(instr.Method.Type().(*types.Signature))
-	values := []llvm.Value{
-		typecode,
-		b.getInterfaceMethodSet(instr.Value.Type()),
-		b.getMethodSignature(instr.Method),
+// getMethodsString returns a string to be used in the "tinygo-methods" string
+// attribute for interface functions.
+func (c *compilerContext) getMethodsString(itf *types.Interface) string {
+	methods := make([]string, itf.NumMethods())
+	for i := range methods {
+		methods[i] = c.getMethodSignatureName(itf.Method(i))
 	}
-	fn := b.createRuntimeCall("interfaceMethod", values, "invoke.func")
-	return b.CreateIntToPtr(fn, llvmFnType, "invoke.func.cast")
+	return strings.Join(methods, "; ")
 }
 
-// getInvokeCall creates and returns the function pointer and parameters of an
-// interface call.
-func (b *builder) getInvokeCall(instr *ssa.CallCommon) (llvm.Value, []llvm.Value) {
-	// Call an interface method with dynamic dispatch.
-	itf := b.getValue(instr.Value) // interface
-
-	typecode := b.CreateExtractValue(itf, 0, "invoke.typecode")
-	fnCast := b.getInvokePtr(instr, typecode)
-	receiverValue := b.CreateExtractValue(itf, 1, "invoke.func.receiver")
-
-	args := []llvm.Value{receiverValue}
-	for _, arg := range instr.Args {
-		args = append(args, b.getValue(arg))
+// getInterfaceImplementsfunc returns a declared function that works as a type
+// switch. The interface lowering pass will define this function.
+func (c *compilerContext) getInterfaceImplementsFunc(assertedType types.Type) llvm.Value {
+	fnName := getTypeCodeName(assertedType.Underlying()) + ".$typeassert"
+	llvmFn := c.mod.NamedFunction(fnName)
+	if llvmFn.IsNil() {
+		llvmFnType := llvm.FunctionType(c.ctx.Int1Type(), []llvm.Type{c.uintptrType}, false)
+		llvmFn = llvm.AddFunction(c.mod, fnName, llvmFnType)
+		c.addStandardDeclaredAttributes(llvmFn)
+		methods := c.getMethodsString(assertedType.Underlying().(*types.Interface))
+		llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("tinygo-methods", methods))
 	}
-	// Add the context parameter. An interface call never takes a context but we
-	// have to supply the parameter anyway.
-	args = append(args, llvm.Undef(b.i8ptrType))
-	// Add the parent goroutine handle.
-	args = append(args, llvm.Undef(b.i8ptrType))
+	return llvmFn
+}
 
-	return fnCast, args
+// getInvokeFunction returns the thunk to call the given interface method. The
+// thunk is declared, not defined: it will be defined by the interface lowering
+// pass.
+func (c *compilerContext) getInvokeFunction(instr *ssa.CallCommon) llvm.Value {
+	fnName := getTypeCodeName(instr.Value.Type().Underlying()) + "." + instr.Method.Name() + "$invoke"
+	llvmFn := c.mod.NamedFunction(fnName)
+	if llvmFn.IsNil() {
+		sig := instr.Method.Type().(*types.Signature)
+		var paramTuple []*types.Var
+		for i := 0; i < sig.Params().Len(); i++ {
+			paramTuple = append(paramTuple, sig.Params().At(i))
+		}
+		paramTuple = append(paramTuple, types.NewVar(token.NoPos, nil, "$typecode", types.Typ[types.Uintptr]))
+		llvmFnType := c.getRawFuncType(types.NewSignature(sig.Recv(), types.NewTuple(paramTuple...), sig.Results(), false)).ElementType()
+		llvmFn = llvm.AddFunction(c.mod, fnName, llvmFnType)
+		c.addStandardDeclaredAttributes(llvmFn)
+		llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("tinygo-invoke", c.getMethodSignatureName(instr.Method)))
+		methods := c.getMethodsString(instr.Value.Type().Underlying().(*types.Interface))
+		llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("tinygo-methods", methods))
+	}
+	return llvmFn
 }
 
 // getInterfaceInvokeWrapper returns a wrapper for the given method so it can be
@@ -474,7 +509,7 @@ func (c *compilerContext) getInterfaceInvokeWrapper(fn *ssa.Function, llvmFn llv
 	paramTypes := append([]llvm.Type{c.i8ptrType}, fnType.ParamTypes()[len(expandedReceiverType):]...)
 	wrapFnType := llvm.FunctionType(fnType.ReturnType(), paramTypes, false)
 	wrapper = llvm.AddFunction(c.mod, wrapperName, wrapFnType)
-	wrapper.LastParam().SetName("parentHandle")
+	c.addStandardAttributes(wrapper)
 
 	wrapper.SetLinkage(llvm.LinkOnceODRLinkage)
 	wrapper.SetUnnamedAddr(true)
@@ -536,23 +571,77 @@ func signature(sig *types.Signature) string {
 			if i > 0 {
 				s += ", "
 			}
-			s += sig.Params().At(i).Type().String()
+			s += typestring(sig.Params().At(i).Type())
 		}
 		s += ")"
 	}
 	if sig.Results().Len() == 0 {
 		// keep as-is
 	} else if sig.Results().Len() == 1 {
-		s += " " + sig.Results().At(0).Type().String()
+		s += " " + typestring(sig.Results().At(0).Type())
 	} else {
 		s += " ("
 		for i := 0; i < sig.Results().Len(); i++ {
 			if i > 0 {
 				s += ", "
 			}
-			s += sig.Results().At(i).Type().String()
+			s += typestring(sig.Results().At(i).Type())
 		}
 		s += ")"
 	}
 	return s
 }
+
+// typestring returns a stable (human-readable) type string for the given type
+// that can be used for interface equality checks. It is almost (but not
+// exactly) the same as calling t.String(). The main difference is some
+// normalization around `byte` vs `uint8` for example.
+func typestring(t types.Type) string {
+	// See: https://github.com/golang/go/blob/master/src/go/types/typestring.go
+	switch t := t.(type) {
+	case *types.Array:
+		return "[" + strconv.FormatInt(t.Len(), 10) + "]" + typestring(t.Elem())
+	case *types.Basic:
+		return basicTypes[t.Kind()]
+	case *types.Chan:
+		switch t.Dir() {
+		case types.SendRecv:
+			return "chan (" + typestring(t.Elem()) + ")"
+		case types.SendOnly:
+			return "chan<- (" + typestring(t.Elem()) + ")"
+		case types.RecvOnly:
+			return "<-chan (" + typestring(t.Elem()) + ")"
+		default:
+			panic("unknown channel direction")
+		}
+	case *types.Interface:
+		methods := make([]string, t.NumMethods())
+		for i := range methods {
+			method := t.Method(i)
+			methods[i] = method.Name() + signature(method.Type().(*types.Signature))
+		}
+		return "interface{" + strings.Join(methods, ";") + "}"
+	case *types.Map:
+		return "map[" + typestring(t.Key()) + "]" + typestring(t.Elem())
+	case *types.Named:
+		return t.String()
+	case *types.Pointer:
+		return "*" + typestring(t.Elem())
+	case *types.Signature:
+		return "func" + signature(t)
+	case *types.Slice:
+		return "[]" + typestring(t.Elem())
+	case *types.Struct:
+		fields := make([]string, t.NumFields())
+		for i := range fields {
+			field := t.Field(i)
+			fields[i] = field.Name() + " " + typestring(field.Type())
+			if tag := t.Tag(i); tag != "" {
+				fields[i] += " " + strconv.Quote(tag)
+			}
+		}
+		return "struct{" + strings.Join(fields, ";") + "}"
+	default:
+		panic("unknown type: " + t.String())
+	}
+}

compiler/interrupt.go

@@ -36,22 +36,22 @@ func (b *builder) createInterruptGlobal(instr *ssa.CallCommon) (llvm.Value, erro
 		// Fall back to a generic error.
 		return llvm.Value{}, b.makeError(instr.Pos(), "interrupt function must be constant")
 	}
+	funcRawPtr, funcContext := b.decodeFuncValue(funcValue, nil)
+	funcPtr := llvm.ConstPtrToInt(funcRawPtr, b.uintptrType)
 
 	// Create a new global of type runtime/interrupt.handle. Globals of this
 	// type are lowered in the interrupt lowering pass.
 	globalType := b.program.ImportedPackage("runtime/interrupt").Type("handle").Type()
 	globalLLVMType := b.getLLVMType(globalType)
-	globalName := "runtime/interrupt.$interrupt" + strconv.FormatInt(id.Int64(), 10)
-	if global := b.mod.NamedGlobal(globalName); !global.IsNil() {
-		return llvm.Value{}, b.makeError(instr.Pos(), "interrupt redeclared in this program")
-	}
+	globalName := b.fn.Package().Pkg.Path() + "$interrupt" + strconv.FormatInt(id.Int64(), 10)
 	global := llvm.AddGlobal(b.mod, globalLLVMType, globalName)
 	global.SetVisibility(llvm.HiddenVisibility)
 	global.SetGlobalConstant(true)
 	global.SetUnnamedAddr(true)
 	initializer := llvm.ConstNull(globalLLVMType)
-	initializer = llvm.ConstInsertValue(initializer, funcValue, []uint32{0})
-	initializer = llvm.ConstInsertValue(initializer, llvm.ConstInt(b.intType, uint64(id.Int64()), true), []uint32{1, 0})
+	initializer = llvm.ConstInsertValue(initializer, funcContext, []uint32{0})
+	initializer = llvm.ConstInsertValue(initializer, funcPtr, []uint32{1})
+	initializer = llvm.ConstInsertValue(initializer, llvm.ConstInt(b.intType, uint64(id.Int64()), true), []uint32{2, 0})
 	global.SetInitializer(initializer)
 
 	// Add debug info to the interrupt global.

compiler/intrinsics.go

@@ -48,3 +48,57 @@ func (b *builder) createMemoryZeroCall(args []ssa.Value) (llvm.Value, error) {
 	b.CreateCall(llvmFn, params, "")
 	return llvm.Value{}, nil
 }
+
+var mathToLLVMMapping = map[string]string{
+	"math.Sqrt":  "llvm.sqrt.f64",
+	"math.Floor": "llvm.floor.f64",
+	"math.Ceil":  "llvm.ceil.f64",
+	"math.Trunc": "llvm.trunc.f64",
+}
+
+// createMathOp tries to lower the given call as a LLVM math intrinsic, if
+// possible. It returns the call result if possible, and a boolean whether it
+// succeeded. If it doesn't succeed, the architecture doesn't support the given
+// intrinsic.
+func (b *builder) createMathOp(call *ssa.CallCommon) (llvm.Value, bool) {
+	// Check whether this intrinsic is supported on the given GOARCH.
+	// If it is unsupported, this can have two reasons:
+	//
+	//  1. LLVM can expand the intrinsic inline (using float instructions), but
+	//     the result doesn't pass the tests of the math package.
+	//  2. LLVM cannot expand the intrinsic inline, will therefore lower it as a
+	//     libm function call, but the libm function call also fails the math
+	//     package tests.
+	//
+	// Whatever the implementation, it must pass the tests in the math package
+	// so unfortunately only the below intrinsic+architecture combinations are
+	// supported.
+	name := call.StaticCallee().RelString(nil)
+	switch name {
+	case "math.Ceil", "math.Floor", "math.Trunc":
+		if b.GOARCH != "wasm" && b.GOARCH != "arm64" {
+			return llvm.Value{}, false
+		}
+	case "math.Sqrt":
+		if b.GOARCH != "wasm" && b.GOARCH != "amd64" && b.GOARCH != "386" {
+			return llvm.Value{}, false
+		}
+	default:
+		return llvm.Value{}, false // only the above functions are supported.
+	}
+
+	llvmFn := b.mod.NamedFunction(mathToLLVMMapping[name])
+	if llvmFn.IsNil() {
+		// The intrinsic doesn't exist yet, so declare it.
+		// At the moment, all supported intrinsics have the form "double
+		// foo(double %x)" so we can hardcode the signature here.
+		llvmType := llvm.FunctionType(b.ctx.DoubleType(), []llvm.Type{b.ctx.DoubleType()}, false)
+		llvmFn = llvm.AddFunction(b.mod, mathToLLVMMapping[name], llvmType)
+	}
+	// Create a call to the intrinsic.
+	args := make([]llvm.Value, len(call.Args))
+	for i, arg := range call.Args {
+		args[i] = b.getValue(arg)
+	}
+	return b.CreateCall(llvmFn, args, ""), true
+}

compiler/ircheck/check.go

@@ -31,7 +31,7 @@ func (c *checker) checkType(t llvm.Type, checked map[llvm.Type]struct{}, special
 		return fmt.Errorf("type %q uses global context", t.String())
 	default:
 		// we used some other context by accident
-		return fmt.Errorf("type %q uses context %v instead of the main context %v", t.Context(), c.ctx)
+		return fmt.Errorf("type %q uses context %v instead of the main context %v", t.String(), t.Context(), c.ctx)
 	}
 
 	// if this is a composite type, check the components of the type

compiler/llvm.go

@@ -1,6 +1,11 @@
 package compiler
 
 import (
+	"fmt"
+	"go/token"
+	"go/types"
+	"math/big"
+
 	"github.com/tinygo-org/tinygo/compiler/llvmutil"
 	"tinygo.org/x/go-llvm"
 )
@@ -8,21 +13,6 @@ import (
 // This file contains helper functions for LLVM that are not exposed in the Go
 // bindings.
 
-// Return a list of values (actually, instructions) where this value is used as
-// an operand.
-func getUses(value llvm.Value) []llvm.Value {
-	if value.IsNil() {
-		return nil
-	}
-	var uses []llvm.Value
-	use := value.FirstUse()
-	for !use.IsNil() {
-		uses = append(uses, use.User())
-		use = use.NextUse()
-	}
-	return uses
-}
-
 // createTemporaryAlloca creates a new alloca in the entry block and adds
 // lifetime start information in the IR signalling that the alloca won't be used
 // before this point.
@@ -44,7 +34,7 @@ func (b *builder) emitLifetimeEnd(ptr, size llvm.Value) {
 // bitcasts, or else allocates a value on the heap if it cannot be packed in the
 // pointer value directly. It returns the pointer with the packed data.
 func (b *builder) emitPointerPack(values []llvm.Value) llvm.Value {
-	return llvmutil.EmitPointerPack(b.Builder, b.mod, b.NeedsStackObjects, values)
+	return llvmutil.EmitPointerPack(b.Builder, b.mod, b.pkg.Path(), b.NeedsStackObjects, values)
 }
 
 // emitPointerUnpack extracts a list of values packed using emitPointerPack.
@@ -67,3 +57,199 @@ func (c *compilerContext) makeGlobalArray(buf []byte, name string, elementType l
 	global.SetInitializer(value)
 	return global
 }
+
+// createObjectLayout returns a LLVM value (of type i8*) that describes where
+// there are pointers in the type t. If all the data fits in a word, it is
+// returned as a word. Otherwise it will store the data in a global.
+//
+// The value contains two pieces of information: the length of the object and
+// which words contain a pointer (indicated by setting the given bit to 1). For
+// arrays, only the element is stored. This works because the GC knows the
+// object size and can therefore know how this value is repeated in the object.
+func (c *compilerContext) createObjectLayout(t llvm.Type, pos token.Pos) llvm.Value {
+	// Use the element type for arrays. This works even for nested arrays.
+	for {
+		kind := t.TypeKind()
+		if kind == llvm.ArrayTypeKind {
+			t = t.ElementType()
+			continue
+		}
+		if kind == llvm.StructTypeKind {
+			fields := t.StructElementTypes()
+			if len(fields) == 1 {
+				t = fields[0]
+				continue
+			}
+		}
+		break
+	}
+
+	// Do a few checks to see whether we need to generate any object layout
+	// information at all.
+	objectSizeBytes := c.targetData.TypeAllocSize(t)
+	pointerSize := c.targetData.TypeAllocSize(c.i8ptrType)
+	pointerAlignment := c.targetData.PrefTypeAlignment(c.i8ptrType)
+	if objectSizeBytes < pointerSize {
+		// Too small to contain a pointer.
+		layout := (uint64(1) << 1) | 1
+		return llvm.ConstIntToPtr(llvm.ConstInt(c.uintptrType, layout, false), c.i8ptrType)
+	}
+	bitmap := c.getPointerBitmap(t, pos)
+	if bitmap.BitLen() == 0 {
+		// There are no pointers in this type, so we can simplify the layout.
+		// TODO: this can be done in many other cases, e.g. when allocating an
+		// array (like [4][]byte, which repeats a slice 4 times).
+		layout := (uint64(1) << 1) | 1
+		return llvm.ConstIntToPtr(llvm.ConstInt(c.uintptrType, layout, false), c.i8ptrType)
+	}
+	if objectSizeBytes%uint64(pointerAlignment) != 0 {
+		// This shouldn't happen except for packed structs, which aren't
+		// currently used.
+		c.addError(pos, "internal error: unexpected object size for object with pointer field")
+		return llvm.ConstNull(c.i8ptrType)
+	}
+	objectSizeWords := objectSizeBytes / uint64(pointerAlignment)
+
+	pointerBits := pointerSize * 8
+	var sizeFieldBits uint64
+	switch pointerBits {
+	case 16:
+		sizeFieldBits = 4
+	case 32:
+		sizeFieldBits = 5
+	case 64:
+		sizeFieldBits = 6
+	default:
+		panic("unknown pointer size")
+	}
+	layoutFieldBits := pointerBits - 1 - sizeFieldBits
+
+	// Try to emit the value as an inline integer. This is possible in most
+	// cases.
+	if objectSizeWords < layoutFieldBits {
+		// If it can be stored directly in the pointer value, do so.
+		// The runtime knows that if the least significant bit of the pointer is
+		// set, the pointer contains the value itself.
+		layout := bitmap.Uint64()<<(sizeFieldBits+1) | (objectSizeWords << 1) | 1
+		return llvm.ConstIntToPtr(llvm.ConstInt(c.uintptrType, layout, false), c.i8ptrType)
+	}
+
+	// Unfortunately, the object layout is too big to fit in a pointer-sized
+	// integer. Store it in a global instead.
+
+	// Try first whether the global already exists. All objects with a
+	// particular name have the same type, so this is possible.
+	globalName := "runtime/gc.layout:" + fmt.Sprintf("%d-%0*x", objectSizeWords, (objectSizeWords+15)/16, bitmap)
+	global := c.mod.NamedGlobal(globalName)
+	if !global.IsNil() {
+		return llvm.ConstBitCast(global, c.i8ptrType)
+	}
+
+	// Create the global initializer.
+	bitmapBytes := make([]byte, int(objectSizeWords+7)/8)
+	bitmap.FillBytes(bitmapBytes)
+	var bitmapByteValues []llvm.Value
+	for _, b := range bitmapBytes {
+		bitmapByteValues = append(bitmapByteValues, llvm.ConstInt(c.ctx.Int8Type(), uint64(b), false))
+	}
+	initializer := c.ctx.ConstStruct([]llvm.Value{
+		llvm.ConstInt(c.uintptrType, objectSizeWords, false),
+		llvm.ConstArray(c.ctx.Int8Type(), bitmapByteValues),
+	}, false)
+
+	global = llvm.AddGlobal(c.mod, initializer.Type(), globalName)
+	global.SetInitializer(initializer)
+	global.SetUnnamedAddr(true)
+	global.SetGlobalConstant(true)
+	global.SetLinkage(llvm.LinkOnceODRLinkage)
+	if c.targetData.PrefTypeAlignment(c.uintptrType) < 2 {
+		// AVR doesn't have alignment by default.
+		global.SetAlignment(2)
+	}
+	if c.Debug && pos != token.NoPos {
+		// Creating a fake global so that the value can be inspected in GDB.
+		// For example, the layout for strings.stringFinder (as of Go version
+		// 1.15) has the following type according to GDB:
+		//   type = struct {
+		//       uintptr numBits;
+		//       uint8 data[33];
+		//   }
+		// ...that's sort of a mixed C/Go type, but it is readable. More
+		// importantly, these object layout globals can be read and printed by
+		// GDB which may be useful for debugging.
+		position := c.program.Fset.Position(pos)
+		diglobal := c.dibuilder.CreateGlobalVariableExpression(c.difiles[position.Filename], llvm.DIGlobalVariableExpression{
+			Name: globalName,
+			File: c.getDIFile(position.Filename),
+			Line: position.Line,
+			Type: c.getDIType(types.NewStruct([]*types.Var{
+				types.NewVar(pos, nil, "numBits", types.Typ[types.Uintptr]),
+				types.NewVar(pos, nil, "data", types.NewArray(types.Typ[types.Byte], int64(len(bitmapByteValues)))),
+			}, nil)),
+			LocalToUnit: false,
+			Expr:        c.dibuilder.CreateExpression(nil),
+		})
+		global.AddMetadata(0, diglobal)
+	}
+
+	return llvm.ConstBitCast(global, c.i8ptrType)
+}
+
+// getPointerBitmap scans the given LLVM type for pointers and sets bits in a
+// bigint at the word offset that contains a pointer. This scan is recursive.
+func (c *compilerContext) getPointerBitmap(typ llvm.Type, pos token.Pos) *big.Int {
+	alignment := c.targetData.PrefTypeAlignment(c.i8ptrType)
+	switch typ.TypeKind() {
+	case llvm.IntegerTypeKind, llvm.FloatTypeKind, llvm.DoubleTypeKind:
+		return big.NewInt(0)
+	case llvm.PointerTypeKind:
+		return big.NewInt(1)
+	case llvm.StructTypeKind:
+		ptrs := big.NewInt(0)
+		if typ.StructName() == "runtime.funcValue" {
+			// Hack: the type runtime.funcValue contains an 'id' field which is
+			// of type uintptr, but before the LowerFuncValues pass it actually
+			// contains a pointer (ptrtoint) to a global. This trips up the
+			// interp package. Therefore, make the id field a pointer for now.
+			typ = c.ctx.StructType([]llvm.Type{c.i8ptrType, c.i8ptrType}, false)
+		}
+		for i, subtyp := range typ.StructElementTypes() {
+			subptrs := c.getPointerBitmap(subtyp, pos)
+			if subptrs.BitLen() == 0 {
+				continue
+			}
+			offset := c.targetData.ElementOffset(typ, i)
+			if offset%uint64(alignment) != 0 {
+				// This error will let the compilation fail, but by continuing
+				// the error can still easily be shown.
+				c.addError(pos, "internal error: allocated struct contains unaligned pointer")
+				continue
+			}
+			subptrs.Lsh(subptrs, uint(offset)/uint(alignment))
+			ptrs.Or(ptrs, subptrs)
+		}
+		return ptrs
+	case llvm.ArrayTypeKind:
+		subtyp := typ.ElementType()
+		subptrs := c.getPointerBitmap(subtyp, pos)
+		ptrs := big.NewInt(0)
+		if subptrs.BitLen() == 0 {
+			return ptrs
+		}
+		elementSize := c.targetData.TypeAllocSize(subtyp)
+		if elementSize%uint64(alignment) != 0 {
+			// This error will let the compilation fail (but continues so that
+			// other errors can be shown).
+			c.addError(pos, "internal error: allocated array contains unaligned pointer")
+			return ptrs
+		}
+		for i := 0; i < typ.ArrayLength(); i++ {
+			ptrs.Lsh(ptrs, uint(elementSize)/uint(alignment))
+			ptrs.Or(ptrs, subptrs)
+		}
+		return ptrs
+	default:
+		// Should not happen.
+		panic("unknown LLVM type")
+	}
+}

compiler/llvmutil/llvm.go

@@ -34,6 +34,7 @@ func CreateEntryBlockAlloca(builder llvm.Builder, t llvm.Type, name string) llvm
 func CreateTemporaryAlloca(builder llvm.Builder, mod llvm.Module, t llvm.Type, name string) (alloca, bitcast, size llvm.Value) {
 	ctx := t.Context()
 	targetData := llvm.NewTargetData(mod.DataLayout())
+	defer targetData.Dispose()
 	i8ptrType := llvm.PointerType(ctx.Int8Type(), 0)
 	alloca = CreateEntryBlockAlloca(builder, t, name)
 	bitcast = builder.CreateBitCast(alloca, i8ptrType, name+".bitcast")
@@ -46,6 +47,7 @@ func CreateTemporaryAlloca(builder llvm.Builder, mod llvm.Module, t llvm.Type, n
 func CreateInstructionAlloca(builder llvm.Builder, mod llvm.Module, t llvm.Type, inst llvm.Value, name string) llvm.Value {
 	ctx := mod.Context()
 	targetData := llvm.NewTargetData(mod.DataLayout())
+	defer targetData.Dispose()
 	i8ptrType := llvm.PointerType(ctx.Int8Type(), 0)
 
 	alloca := CreateEntryBlockAlloca(builder, t, name)

compiler/llvmutil/wordpack.go

@@ -12,11 +12,12 @@ import (
 // bitcasts, or else allocates a value on the heap if it cannot be packed in the
 // pointer value directly. It returns the pointer with the packed data.
 // If the values are all constants, they are be stored in a constant global and deduplicated.
-func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bool, values []llvm.Value) llvm.Value {
+func EmitPointerPack(builder llvm.Builder, mod llvm.Module, prefix string, needsStackObjects bool, values []llvm.Value) llvm.Value {
 	ctx := mod.Context()
 	targetData := llvm.NewTargetData(mod.DataLayout())
+	defer targetData.Dispose()
 	i8ptrType := llvm.PointerType(mod.Context().Int8Type(), 0)
-	uintptrType := ctx.IntType(llvm.NewTargetData(mod.DataLayout()).PointerSize() * 8)
+	uintptrType := ctx.IntType(targetData.PointerSize() * 8)
 
 	valueTypes := make([]llvm.Type, len(values))
 	for i, value := range values {
@@ -83,12 +84,11 @@ func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bo
 		if constant {
 			// The data is known at compile time, so store it in a constant global.
 			// The global address is marked as unnamed, which allows LLVM to merge duplicates.
-			funcName := builder.GetInsertBlock().Parent().Name()
-			global := llvm.AddGlobal(mod, packedType, funcName+"$pack")
+			global := llvm.AddGlobal(mod, packedType, prefix+"$pack")
 			global.SetInitializer(ctx.ConstStruct(values, false))
 			global.SetGlobalConstant(true)
 			global.SetUnnamedAddr(true)
-			global.SetLinkage(llvm.PrivateLinkage)
+			global.SetLinkage(llvm.InternalLinkage)
 			return llvm.ConstBitCast(global, i8ptrType)
 		}
 
@@ -97,15 +97,14 @@ func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bo
 		alloc := mod.NamedFunction("runtime.alloc")
 		packedHeapAlloc := builder.CreateCall(alloc, []llvm.Value{
 			sizeValue,
-			llvm.Undef(i8ptrType),            // unused context parameter
-			llvm.ConstPointerNull(i8ptrType), // coroutine handle
+			llvm.ConstNull(i8ptrType),
+			llvm.Undef(i8ptrType), // unused context parameter
 		}, "")
 		if needsStackObjects {
 			trackPointer := mod.NamedFunction("runtime.trackPointer")
 			builder.CreateCall(trackPointer, []llvm.Value{
 				packedHeapAlloc,
-				llvm.Undef(i8ptrType),            // unused context parameter
-				llvm.ConstPointerNull(i8ptrType), // coroutine handle
+				llvm.Undef(i8ptrType), // unused context parameter
 			}, "")
 		}
 		packedAlloc := builder.CreateBitCast(packedHeapAlloc, llvm.PointerType(packedType, 0), "")
@@ -129,8 +128,9 @@ func EmitPointerPack(builder llvm.Builder, mod llvm.Module, needsStackObjects bo
 func EmitPointerUnpack(builder llvm.Builder, mod llvm.Module, ptr llvm.Value, valueTypes []llvm.Type) []llvm.Value {
 	ctx := mod.Context()
 	targetData := llvm.NewTargetData(mod.DataLayout())
+	defer targetData.Dispose()
 	i8ptrType := llvm.PointerType(mod.Context().Int8Type(), 0)
-	uintptrType := ctx.IntType(llvm.NewTargetData(mod.DataLayout()).PointerSize() * 8)
+	uintptrType := ctx.IntType(targetData.PointerSize() * 8)
 
 	packedType := ctx.StructType(valueTypes, false)
 

compiler/map.go

@@ -10,6 +10,13 @@ import (
 	"tinygo.org/x/go-llvm"
 )
 
+// constants for hashmap algorithms; must match src/runtime/hashmap.go
+const (
+	hashmapAlgorithmBinary = iota
+	hashmapAlgorithmString
+	hashmapAlgorithmInterface
+)
+
 // createMakeMap creates a new map object (runtime.hashmap) by allocating and
 // initializing an appropriately sized object.
 func (b *builder) createMakeMap(expr *ssa.MakeMap) (llvm.Value, error) {
@@ -17,22 +24,27 @@ func (b *builder) createMakeMap(expr *ssa.MakeMap) (llvm.Value, error) {
 	keyType := mapType.Key().Underlying()
 	llvmValueType := b.getLLVMType(mapType.Elem().Underlying())
 	var llvmKeyType llvm.Type
+	var alg uint64 // must match values in src/runtime/hashmap.go
 	if t, ok := keyType.(*types.Basic); ok && t.Info()&types.IsString != 0 {
 		// String keys.
 		llvmKeyType = b.getLLVMType(keyType)
+		alg = hashmapAlgorithmString
 	} else if hashmapIsBinaryKey(keyType) {
 		// Trivially comparable keys.
 		llvmKeyType = b.getLLVMType(keyType)
+		alg = hashmapAlgorithmBinary
 	} else {
 		// All other keys. Implemented as map[interface{}]valueType for ease of
 		// implementation.
 		llvmKeyType = b.getLLVMRuntimeType("_interface")
+		alg = hashmapAlgorithmInterface
 	}
 	keySize := b.targetData.TypeAllocSize(llvmKeyType)
 	valueSize := b.targetData.TypeAllocSize(llvmValueType)
 	llvmKeySize := llvm.ConstInt(b.ctx.Int8Type(), keySize, false)
 	llvmValueSize := llvm.ConstInt(b.ctx.Int8Type(), valueSize, false)
 	sizeHint := llvm.ConstInt(b.uintptrType, 8, false)
+	algEnum := llvm.ConstInt(b.ctx.Int8Type(), alg, false)
 	if expr.Reserve != nil {
 		sizeHint = b.getValue(expr.Reserve)
 		var err error
@@ -41,7 +53,7 @@ func (b *builder) createMakeMap(expr *ssa.MakeMap) (llvm.Value, error) {
 			return llvm.Value{}, err
 		}
 	}
-	hashmap := b.createRuntimeCall("hashmapMake", []llvm.Value{llvmKeySize, llvmValueSize, sizeHint}, "")
+	hashmap := b.createRuntimeCall("hashmapMake", []llvm.Value{llvmKeySize, llvmValueSize, sizeHint, algEnum}, "")
 	return hashmap, nil
 }
 
@@ -167,6 +179,66 @@ func (b *builder) createMapDelete(keyType types.Type, m, key llvm.Value, pos tok
 	}
 }
 
+// createMapIteratorNext lowers the *ssa.Next instruction for iterating over a
+// map. It returns a tuple of {bool, key, value} with the result of the
+// iteration.
+func (b *builder) createMapIteratorNext(rangeVal ssa.Value, llvmRangeVal, it llvm.Value) llvm.Value {
+	// Determine the type of the values to return from the *ssa.Next
+	// instruction. It is returned as {bool, keyType, valueType}.
+	keyType := rangeVal.Type().Underlying().(*types.Map).Key()
+	valueType := rangeVal.Type().Underlying().(*types.Map).Elem()
+	llvmKeyType := b.getLLVMType(keyType)
+	llvmValueType := b.getLLVMType(valueType)
+
+	// There is a special case in which keys are stored as an interface value
+	// instead of the value they normally are. This happens for non-trivially
+	// comparable types such as float32 or some structs.
+	isKeyStoredAsInterface := false
+	if t, ok := keyType.Underlying().(*types.Basic); ok && t.Info()&types.IsString != 0 {
+		// key is a string
+	} else if hashmapIsBinaryKey(keyType) {
+		// key can be compared with runtime.memequal
+	} else {
+		// The key is stored as an interface value, and may or may not be an
+		// interface type (for example, float32 keys are stored as an interface
+		// value).
+		if _, ok := keyType.Underlying().(*types.Interface); !ok {
+			isKeyStoredAsInterface = true
+		}
+	}
+
+	// Determine the type of the key as stored in the map.
+	llvmStoredKeyType := llvmKeyType
+	if isKeyStoredAsInterface {
+		llvmStoredKeyType = b.getLLVMRuntimeType("_interface")
+	}
+
+	// Extract the key and value from the map.
+	mapKeyAlloca, mapKeyPtr, mapKeySize := b.createTemporaryAlloca(llvmStoredKeyType, "range.key")
+	mapValueAlloca, mapValuePtr, mapValueSize := b.createTemporaryAlloca(llvmValueType, "range.value")
+	ok := b.createRuntimeCall("hashmapNext", []llvm.Value{llvmRangeVal, it, mapKeyPtr, mapValuePtr}, "range.next")
+	mapKey := b.CreateLoad(mapKeyAlloca, "")
+	mapValue := b.CreateLoad(mapValueAlloca, "")
+
+	if isKeyStoredAsInterface {
+		// The key is stored as an interface but it isn't of interface type.
+		// Extract the underlying value.
+		mapKey = b.extractValueFromInterface(mapKey, llvmKeyType)
+	}
+
+	// End the lifetimes of the allocas, because we're done with them.
+	b.emitLifetimeEnd(mapKeyPtr, mapKeySize)
+	b.emitLifetimeEnd(mapValuePtr, mapValueSize)
+
+	// Construct the *ssa.Next return value: {ok, mapKey, mapValue}
+	tuple := llvm.Undef(b.ctx.StructType([]llvm.Type{b.ctx.Int1Type(), llvmKeyType, llvmValueType}, false))
+	tuple = b.CreateInsertValue(tuple, ok, 0, "")
+	tuple = b.CreateInsertValue(tuple, mapKey, 1, "")
+	tuple = b.CreateInsertValue(tuple, mapValue, 2, "")
+
+	return tuple
+}
+
 // Returns true if this key type does not contain strings, interfaces etc., so
 // can be compared with runtime.memequal.
 func hashmapIsBinaryKey(keyType types.Type) bool {

compiler/sizes.go

@@ -45,7 +45,11 @@ func (s *stdSizes) Alignof(T types.Type) int64 {
 		if t.Info()&types.IsString != 0 {
 			return s.PtrSize
 		}
+	case *types.Signature:
+		// Even though functions in tinygo are 2 pointers, they are not 2 pointer aligned
+		return s.PtrSize
 	}
+
 	a := s.Sizeof(T) // may be 0
 	// spec: "For a variable x of any type: unsafe.Alignof(x) is at least 1."
 	if a < 1 {

compiler/symbol.go

@@ -24,7 +24,9 @@ type functionInfo struct {
 	module     string     // go:wasm-module
 	importName string     // go:linkname, go:export - The name the developer assigns
 	linkName   string     // go:linkname, go:export - The name that we map for the particular module -> importName
+	section    string     // go:section - object file section name
 	exported   bool       // go:export, CGo
+	interrupt  bool       // go:interrupt
 	nobounds   bool       // go:nobounds
 	variadic   bool       // go:variadic (CGo only)
 	inline     inlineType // go:inline
@@ -82,7 +84,6 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 	// closures and bound methods, but should be optimized away when not used.
 	if !info.exported {
 		paramInfos = append(paramInfos, paramInfo{llvmType: c.i8ptrType, name: "context", flags: 0})
-		paramInfos = append(paramInfos, paramInfo{llvmType: c.i8ptrType, name: "parentHandle", flags: 0})
 	}
 
 	var paramTypes []llvm.Type
@@ -107,6 +108,7 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 			llvmFn.AddFunctionAttr(attr)
 		}
 	}
+	c.addStandardDeclaredAttributes(llvmFn)
 
 	dereferenceableOrNullKind := llvm.AttributeKindID("dereferenceable_or_null")
 	for i, info := range paramInfos {
@@ -139,6 +141,17 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 		for _, attrName := range []string{"noalias", "nonnull"} {
 			llvmFn.AddAttributeAtIndex(0, c.ctx.CreateEnumAttribute(llvm.AttributeKindID(attrName), 0))
 		}
+	case "runtime.sliceAppend":
+		// Appending a slice will only read the to-be-appended slice, it won't
+		// be modified.
+		llvmFn.AddAttributeAtIndex(2, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nocapture"), 0))
+		llvmFn.AddAttributeAtIndex(2, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("readonly"), 0))
+	case "runtime.sliceCopy":
+		// Copying a slice won't capture any of the parameters.
+		llvmFn.AddAttributeAtIndex(1, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("writeonly"), 0))
+		llvmFn.AddAttributeAtIndex(1, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nocapture"), 0))
+		llvmFn.AddAttributeAtIndex(2, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("readonly"), 0))
+		llvmFn.AddAttributeAtIndex(2, c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nocapture"), 0))
 	case "runtime.trackPointer":
 		// This function is necessary for tracking pointers on the stack in a
 		// portable way (see gc_stack_portable.go). Indicate to the optimizer
@@ -178,7 +191,7 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 	// should be created right away.
 	// The exception is the package initializer, which does appear in the
 	// *ssa.Package members and so shouldn't be created here.
-	if fn.Synthetic != "" && fn.Synthetic != "package initializer" {
+	if fn.Synthetic != "" && fn.Synthetic != "package initializer" && fn.Synthetic != "generic function" {
 		irbuilder := c.ctx.NewBuilder()
 		b := newBuilder(c, irbuilder, fn)
 		b.createFunction()
@@ -194,14 +207,9 @@ func (c *compilerContext) getFunction(fn *ssa.Function) llvm.Value {
 // present in *ssa.Function, such as the link name and whether it should be
 // exported.
 func (c *compilerContext) getFunctionInfo(f *ssa.Function) functionInfo {
-	info := functionInfo{}
-	if strings.HasPrefix(f.Name(), "C.") {
-		// Created by CGo: such a name cannot be created by regular C code.
-		info.linkName = f.Name()[2:]
-		info.exported = true
-	} else {
+	info := functionInfo{
 		// Pick the default linkName.
-		info.linkName = f.RelString(nil)
+		linkName: f.RelString(nil),
 	}
 	// Check for //go: pragmas, which may change the link name (among others).
 	info.parsePragmas(f)
@@ -238,6 +246,10 @@ func (info *functionInfo) parsePragmas(f *ssa.Function) {
 
 				importName = parts[1]
 				info.exported = true
+			case "//go:interrupt":
+				if hasUnsafeImport(f.Pkg.Pkg) {
+					info.interrupt = true
+				}
 			case "//go:wasm-module":
 				// Alternative comment for setting the import module.
 				if len(parts) != 2 {
@@ -259,6 +271,10 @@ func (info *functionInfo) parsePragmas(f *ssa.Function) {
 				if hasUnsafeImport(f.Pkg.Pkg) {
 					info.linkName = parts[2]
 				}
+			case "//go:section":
+				if len(parts) == 2 && hasUnsafeImport(f.Pkg.Pkg) {
+					info.section = parts[1]
+				}
 			case "//go:nobounds":
 				// Skip bounds checking in this function. Useful for some
 				// runtime functions.
@@ -307,6 +323,53 @@ func getParams(sig *types.Signature) []*types.Var {
 	return params
 }
 
+// addStandardDeclaredAttributes adds attributes that are set for any function,
+// whether declared or defined.
+func (c *compilerContext) addStandardDeclaredAttributes(llvmFn llvm.Value) {
+	if c.SizeLevel >= 1 {
+		// Set the "optsize" attribute to make slightly smaller binaries at the
+		// cost of minimal performance loss (-Os in Clang).
+		kind := llvm.AttributeKindID("optsize")
+		attr := c.ctx.CreateEnumAttribute(kind, 0)
+		llvmFn.AddFunctionAttr(attr)
+	}
+	if c.SizeLevel >= 2 {
+		// Set the "minsize" attribute to reduce code size even further,
+		// regardless of performance loss (-Oz in Clang).
+		kind := llvm.AttributeKindID("minsize")
+		attr := c.ctx.CreateEnumAttribute(kind, 0)
+		llvmFn.AddFunctionAttr(attr)
+	}
+	if c.CPU != "" {
+		llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("target-cpu", c.CPU))
+	}
+	if c.Features != "" {
+		llvmFn.AddFunctionAttr(c.ctx.CreateStringAttribute("target-features", c.Features))
+	}
+}
+
+// addStandardDefinedAttributes adds the set of attributes that are added to
+// every function defined by TinyGo (even thunks/wrappers), possibly depending
+// on the architecture. It does not set attributes only set for declared
+// functions, use addStandardDeclaredAttributes for this.
+func (c *compilerContext) addStandardDefinedAttributes(llvmFn llvm.Value) {
+	// TinyGo does not currently raise exceptions, so set the 'nounwind' flag.
+	// This behavior matches Clang when compiling C source files.
+	// It reduces binary size on Linux a little bit on non-x86_64 targets by
+	// eliminating exception tables for these functions.
+	llvmFn.AddFunctionAttr(c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nounwind"), 0))
+	if strings.Split(c.Triple, "-")[0] == "x86_64" {
+		// Required by the ABI.
+		llvmFn.AddFunctionAttr(c.ctx.CreateEnumAttribute(llvm.AttributeKindID("uwtable"), 0))
+	}
+}
+
+// addStandardAttribute adds all attributes added to defined functions.
+func (c *compilerContext) addStandardAttributes(llvmFn llvm.Value) {
+	c.addStandardDeclaredAttributes(llvmFn)
+	c.addStandardDefinedAttributes(llvmFn)
+}
+
 // globalInfo contains some information about a specific global. By default,
 // linkName is equal to .RelString(nil) on a global and extern is false, but for
 // some symbols this is different (due to //go:extern for example).
@@ -314,6 +377,7 @@ type globalInfo struct {
 	linkName string // go:extern
 	extern   bool   // go:extern
 	align    int    // go:align
+	section  string // go:section
 }
 
 // loadASTComments loads comments on globals from the AST, for use later in the
@@ -355,16 +419,18 @@ func (c *compilerContext) getGlobal(g *ssa.Global) llvm.Value {
 
 		// Set alignment from the //go:align comment.
 		var alignInBits uint32
-		if info.align < 0 || info.align&(info.align-1) != 0 {
+		alignment := c.targetData.ABITypeAlignment(llvmType)
+		if info.align > alignment {
+			alignment = info.align
+		}
+		if alignment <= 0 || alignment&(alignment-1) != 0 {
 			// Check for power-of-two (or 0).
 			// See: https://stackoverflow.com/a/108360
 			c.addError(g.Pos(), "global variable alignment must be a positive power of two")
 		} else {
 			// Set the alignment only when it is a power of two.
-			alignInBits = uint32(info.align) ^ uint32(info.align-1)
-			if info.align > c.targetData.ABITypeAlignment(llvmType) {
-				llvmGlobal.SetAlignment(info.align)
-			}
+			alignInBits = uint32(alignment) ^ uint32(alignment-1)
+			llvmGlobal.SetAlignment(alignment)
 		}
 
 		if c.Debug && !info.extern {
@@ -388,20 +454,14 @@ func (c *compilerContext) getGlobal(g *ssa.Global) llvm.Value {
 
 // getGlobalInfo returns some information about a specific global.
 func (c *compilerContext) getGlobalInfo(g *ssa.Global) globalInfo {
-	info := globalInfo{}
-	if strings.HasPrefix(g.Name(), "C.") {
-		// Created by CGo: such a name cannot be created by regular C code.
-		info.linkName = g.Name()[2:]
-		info.extern = true
-	} else {
+	info := globalInfo{
 		// Pick the default linkName.
-		info.linkName = g.RelString(nil)
-		// Check for //go: pragmas, which may change the link name (among
-		// others).
-		doc := c.astComments[info.linkName]
-		if doc != nil {
-			info.parsePragmas(doc)
-		}
+		linkName: g.RelString(nil),
+	}
+	// Check for //go: pragmas, which may change the link name (among others).
+	doc := c.astComments[info.linkName]
+	if doc != nil {
+		info.parsePragmas(doc)
 	}
 	return info
 }
@@ -425,6 +485,10 @@ func (info *globalInfo) parsePragmas(doc *ast.CommentGroup) {
 			if err == nil {
 				info.align = align
 			}
+		case "//go:section":
+			if len(parts) == 2 {
+				info.section = parts[1]
+			}
 		}
 	}
 }

compiler/syscall.go

@@ -10,11 +10,11 @@ import (
 	"tinygo.org/x/go-llvm"
 )
 
-// createSyscall emits an inline system call instruction, depending on the
-// target OS/arch.
-func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
+// createRawSyscall creates a system call with the provided system call number
+// and returns the result as a single integer (the system call result). The
+// result is not further interpreted.
+func (b *builder) createRawSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 	num := b.getValue(call.Args[0])
-	var syscallResult llvm.Value
 	switch {
 	case b.GOARCH == "amd64":
 		if b.GOOS == "darwin" {
@@ -56,8 +56,8 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		}
 		constraints += ",~{rcx},~{r11}"
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-		target := llvm.InlineAsm(fnType, "syscall", constraints, true, false, llvm.InlineAsmDialectIntel)
-		syscallResult = b.CreateCall(target, args, "")
+		target := llvm.InlineAsm(fnType, "syscall", constraints, true, false, llvm.InlineAsmDialectIntel, false)
+		return b.CreateCall(target, args, ""), nil
 	case b.GOARCH == "386" && b.GOOS == "linux":
 		// Sources:
 		//   syscall(2) man page
@@ -82,8 +82,8 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 			argTypes = append(argTypes, llvmValue.Type())
 		}
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-		target := llvm.InlineAsm(fnType, "int 0x80", constraints, true, false, llvm.InlineAsmDialectIntel)
-		syscallResult = b.CreateCall(target, args, "")
+		target := llvm.InlineAsm(fnType, "int 0x80", constraints, true, false, llvm.InlineAsmDialectIntel, false)
+		return b.CreateCall(target, args, ""), nil
 	case b.GOARCH == "arm" && b.GOOS == "linux":
 		// Implement the EABI system call convention for Linux.
 		// Source: syscall(2) man page.
@@ -114,8 +114,8 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 			constraints += ",~{r" + strconv.Itoa(i) + "}"
 		}
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0)
-		syscallResult = b.CreateCall(target, args, "")
+		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0, false)
+		return b.CreateCall(target, args, ""), nil
 	case b.GOARCH == "arm64" && b.GOOS == "linux":
 		// Source: syscall(2) man page.
 		args := []llvm.Value{}
@@ -146,13 +146,22 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		}
 		constraints += ",~{x16},~{x17}" // scratch registers
 		fnType := llvm.FunctionType(b.uintptrType, argTypes, false)
-		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0)
-		syscallResult = b.CreateCall(target, args, "")
+		target := llvm.InlineAsm(fnType, "svc #0", constraints, true, false, 0, false)
+		return b.CreateCall(target, args, ""), nil
 	default:
 		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS+"/"+b.GOARCH)
 	}
+}
+
+// createSyscall emits instructions for the syscall.Syscall* family of
+// functions, depending on the target OS/arch.
+func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 	switch b.GOOS {
-	case "linux", "freebsd":
+	case "linux":
+		syscallResult, err := b.createRawSyscall(call)
+		if err != nil {
+			return syscallResult, err
+		}
 		// Return values: r0, r1 uintptr, err Errno
 		// Pseudocode:
 		//     var err uintptr
@@ -171,6 +180,10 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		retval = b.CreateInsertValue(retval, errResult, 2, "")
 		return retval, nil
 	case "darwin":
+		syscallResult, err := b.createRawSyscall(call)
+		if err != nil {
+			return syscallResult, err
+		}
 		// Return values: r0, r1 uintptr, err Errno
 		// Pseudocode:
 		//     var err uintptr
@@ -186,7 +199,71 @@ func (b *builder) createSyscall(call *ssa.CallCommon) (llvm.Value, error) {
 		retval = b.CreateInsertValue(retval, zero, 1, "")
 		retval = b.CreateInsertValue(retval, errResult, 2, "")
 		return retval, nil
+	case "windows":
+		// On Windows, syscall.Syscall* is basically just a function pointer
+		// call. This is complicated in gc because of stack switching and the
+		// different ABI, but easy in TinyGo: just call the function pointer.
+		// The signature looks like this:
+		//   func Syscall(trap, nargs, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
+
+		// Prepare input values.
+		var paramTypes []llvm.Type
+		var params []llvm.Value
+		for _, val := range call.Args[2:] {
+			param := b.getValue(val)
+			params = append(params, param)
+			paramTypes = append(paramTypes, param.Type())
+		}
+		llvmType := llvm.FunctionType(b.uintptrType, paramTypes, false)
+		fn := b.getValue(call.Args[0])
+		fnPtr := b.CreateIntToPtr(fn, llvm.PointerType(llvmType, 0), "")
+
+		// Prepare some functions that will be called later.
+		setLastError := b.mod.NamedFunction("SetLastError")
+		if setLastError.IsNil() {
+			llvmType := llvm.FunctionType(b.ctx.VoidType(), []llvm.Type{b.ctx.Int32Type()}, false)
+			setLastError = llvm.AddFunction(b.mod, "SetLastError", llvmType)
+		}
+		getLastError := b.mod.NamedFunction("GetLastError")
+		if getLastError.IsNil() {
+			llvmType := llvm.FunctionType(b.ctx.Int32Type(), nil, false)
+			getLastError = llvm.AddFunction(b.mod, "GetLastError", llvmType)
+		}
+
+		// Now do the actual call. Pseudocode:
+		//     SetLastError(0)
+		//     r1 = trap(a1, a2, a3, ...)
+		//     err = uintptr(GetLastError())
+		//     return r1, 0, err
+		// Note that SetLastError/GetLastError could be replaced with direct
+		// access to the thread control block, which is probably smaller and
+		// faster. The Go runtime does this in assembly.
+		b.CreateCall(setLastError, []llvm.Value{llvm.ConstNull(b.ctx.Int32Type())}, "")
+		syscallResult := b.CreateCall(fnPtr, params, "")
+		errResult := b.CreateCall(getLastError, nil, "err")
+		if b.uintptrType != b.ctx.Int32Type() {
+			errResult = b.CreateZExt(errResult, b.uintptrType, "err.uintptr")
+		}
+
+		// Return r1, 0, err
+		retval := llvm.ConstNull(b.ctx.StructType([]llvm.Type{b.uintptrType, b.uintptrType, b.uintptrType}, false))
+		retval = b.CreateInsertValue(retval, syscallResult, 0, "")
+		retval = b.CreateInsertValue(retval, errResult, 2, "")
+		return retval, nil
 	default:
 		return llvm.Value{}, b.makeError(call.Pos(), "unknown GOOS/GOARCH for syscall: "+b.GOOS+"/"+b.GOARCH)
 	}
 }
+
+// createRawSyscallNoError emits instructions for the Linux-specific
+// syscall.rawSyscallNoError function.
+func (b *builder) createRawSyscallNoError(call *ssa.CallCommon) (llvm.Value, error) {
+	syscallResult, err := b.createRawSyscall(call)
+	if err != nil {
+		return syscallResult, err
+	}
+	retval := llvm.ConstNull(b.ctx.StructType([]llvm.Type{b.uintptrType, b.uintptrType}, false))
+	retval = b.CreateInsertValue(retval, syscallResult, 0, "")
+	retval = b.CreateInsertValue(retval, llvm.ConstInt(b.uintptrType, 0, false), 1, "")
+	return retval, nil
+}

compiler/testdata/basic.go

@@ -10,6 +10,22 @@ func equalInt(x, y int) bool {
 	return x == y
 }
 
+func divInt(x, y int) int {
+	return x / y
+}
+
+func divUint(x, y uint) uint {
+	return x / y
+}
+
+func remInt(x, y int) int {
+	return x % y
+}
+
+func remUint(x, y uint) uint {
+	return x % y
+}
+
 func floatEQ(x, y float32) bool {
 	return x == y
 }
@@ -55,3 +71,18 @@ func complexMul(x, y complex64) complex64 {
 }
 
 // TODO: complexDiv (requires runtime call)
+
+// A type 'kv' also exists in function foo. Test that these two types don't
+// conflict with each other.
+type kv struct {
+	v float32
+}
+
+func foo(a *kv) {
+	// Define a new 'kv' type.
+	type kv struct {
+		v byte
+	}
+	// Use this type.
+	func(b *kv) {}(nil)
+}

compiler/testdata/basic.ll

@@ -1,74 +1,161 @@
 ; ModuleID = 'basic.go'
 source_filename = "basic.go"
-target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
-target triple = "i686--linux"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-wasi"
+
+%main.kv = type { float }
+%main.kv.0 = type { i8 }
 
 declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
 
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
+declare void @runtime.trackPointer(i8* nocapture readonly, i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.init(i8* %context) unnamed_addr #0 {
 entry:
   ret void
 }
 
-define hidden i32 @main.addInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i32 @main.addInt(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = add i32 %x, %y
   ret i32 %0
 }
 
-define hidden i1 @main.equalInt(i32 %x, i32 %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.equalInt(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = icmp eq i32 %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatEQ(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i32 @main.divInt(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = icmp eq i32 %y, 0
+  br i1 %0, label %divbyzero.throw, label %divbyzero.next
+
+divbyzero.throw:                                  ; preds = %entry
+  call void @runtime.divideByZeroPanic(i8* undef) #0
+  unreachable
+
+divbyzero.next:                                   ; preds = %entry
+  %1 = icmp eq i32 %y, -1
+  %2 = icmp eq i32 %x, -2147483648
+  %3 = and i1 %1, %2
+  %4 = select i1 %3, i32 1, i32 %y
+  %5 = sdiv i32 %x, %4
+  ret i32 %5
+}
+
+declare void @runtime.divideByZeroPanic(i8*)
+
+; Function Attrs: nounwind
+define hidden i32 @main.divUint(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = icmp eq i32 %y, 0
+  br i1 %0, label %divbyzero.throw, label %divbyzero.next
+
+divbyzero.throw:                                  ; preds = %entry
+  call void @runtime.divideByZeroPanic(i8* undef) #0
+  unreachable
+
+divbyzero.next:                                   ; preds = %entry
+  %1 = udiv i32 %x, %y
+  ret i32 %1
+}
+
+; Function Attrs: nounwind
+define hidden i32 @main.remInt(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = icmp eq i32 %y, 0
+  br i1 %0, label %divbyzero.throw, label %divbyzero.next
+
+divbyzero.throw:                                  ; preds = %entry
+  call void @runtime.divideByZeroPanic(i8* undef) #0
+  unreachable
+
+divbyzero.next:                                   ; preds = %entry
+  %1 = icmp eq i32 %y, -1
+  %2 = icmp eq i32 %x, -2147483648
+  %3 = and i1 %1, %2
+  %4 = select i1 %3, i32 1, i32 %y
+  %5 = srem i32 %x, %4
+  ret i32 %5
+}
+
+; Function Attrs: nounwind
+define hidden i32 @main.remUint(i32 %x, i32 %y, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = icmp eq i32 %y, 0
+  br i1 %0, label %divbyzero.throw, label %divbyzero.next
+
+divbyzero.throw:                                  ; preds = %entry
+  call void @runtime.divideByZeroPanic(i8* undef) #0
+  unreachable
+
+divbyzero.next:                                   ; preds = %entry
+  %1 = urem i32 %x, %y
+  ret i32 %1
+}
+
+; Function Attrs: nounwind
+define hidden i1 @main.floatEQ(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp oeq float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatNE(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.floatNE(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp une float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatLower(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.floatLower(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp olt float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatLowerEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.floatLowerEqual(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp ole float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatGreater(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.floatGreater(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp ogt float %x, %y
   ret i1 %0
 }
 
-define hidden i1 @main.floatGreaterEqual(float %x, float %y, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i1 @main.floatGreaterEqual(float %x, float %y, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fcmp oge float %x, %y
   ret i1 %0
 }
 
-define hidden float @main.complexReal(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden float @main.complexReal(float %x.r, float %x.i, i8* %context) unnamed_addr #0 {
 entry:
   ret float %x.r
 }
 
-define hidden float @main.complexImag(float %x.r, float %x.i, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden float @main.complexImag(float %x.r, float %x.i, i8* %context) unnamed_addr #0 {
 entry:
   ret float %x.i
 }
 
-define hidden { float, float } @main.complexAdd(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden { float, float } @main.complexAdd(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fadd float %x.r, %y.r
   %1 = fadd float %x.i, %y.i
@@ -77,7 +164,8 @@ entry:
   ret { float, float } %3
 }
 
-define hidden { float, float } @main.complexSub(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden { float, float } @main.complexSub(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fsub float %x.r, %y.r
   %1 = fsub float %x.i, %y.i
@@ -86,7 +174,8 @@ entry:
   ret { float, float } %3
 }
 
-define hidden { float, float } @main.complexMul(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden { float, float } @main.complexMul(float %x.r, float %x.i, float %y.r, float %y.i, i8* %context) unnamed_addr #0 {
 entry:
   %0 = fmul float %x.r, %y.r
   %1 = fmul float %x.i, %y.i
@@ -98,3 +187,18 @@ entry:
   %7 = insertvalue { float, float } %6, float %5, 1
   ret { float, float } %7
 }
+
+; Function Attrs: nounwind
+define hidden void @main.foo(%main.kv* dereferenceable_or_null(4) %a, i8* %context) unnamed_addr #0 {
+entry:
+  call void @"main.foo$1"(%main.kv.0* null, i8* undef)
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @"main.foo$1"(%main.kv.0* dereferenceable_or_null(1) %b, i8* %context) unnamed_addr #0 {
+entry:
+  ret void
+}
+
+attributes #0 = { nounwind }

compiler/testdata/channel.go

@@ -0,0 +1,25 @@
+package main
+
+func chanIntSend(ch chan int) {
+	ch <- 3
+}
+
+func chanIntRecv(ch chan int) {
+	<-ch
+}
+
+func chanZeroSend(ch chan struct{}) {
+	ch <- struct{}{}
+}
+
+func chanZeroRecv(ch chan struct{}) {
+	<-ch
+}
+
+func selectZeroRecv(ch1 chan int, ch2 chan struct{}) {
+	select {
+	case ch1 <- 1:
+	case <-ch2:
+	default:
+	}
+}

compiler/testdata/channel.ll

@@ -0,0 +1,128 @@
+; ModuleID = 'channel.go'
+source_filename = "channel.go"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-wasi"
+
+%runtime.channel = type { i32, i32, i8, %runtime.channelBlockedList*, i32, i32, i32, i8* }
+%runtime.channelBlockedList = type { %runtime.channelBlockedList*, %"internal/task.Task"*, %runtime.chanSelectState*, { %runtime.channelBlockedList*, i32, i32 } }
+%"internal/task.Task" = type { %"internal/task.Task"*, i8*, i64, %"internal/task.gcData", %"internal/task.state" }
+%"internal/task.gcData" = type { i8* }
+%"internal/task.state" = type { i32, i8*, %"internal/task.stackState", i1 }
+%"internal/task.stackState" = type { i32, i32 }
+%runtime.chanSelectState = type { %runtime.channel*, i8* }
+
+declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
+
+declare void @runtime.trackPointer(i8* nocapture readonly, i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.init(i8* %context) unnamed_addr #0 {
+entry:
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.chanIntSend(%runtime.channel* dereferenceable_or_null(32) %ch, i8* %context) unnamed_addr #0 {
+entry:
+  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %chan.value = alloca i32, align 4
+  %chan.value.bitcast = bitcast i32* %chan.value to i8*
+  call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %chan.value.bitcast)
+  store i32 3, i32* %chan.value, align 4
+  %chan.blockedList.bitcast = bitcast %runtime.channelBlockedList* %chan.blockedList to i8*
+  call void @llvm.lifetime.start.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  call void @runtime.chanSend(%runtime.channel* %ch, i8* nonnull %chan.value.bitcast, %runtime.channelBlockedList* nonnull %chan.blockedList, i8* undef) #0
+  call void @llvm.lifetime.end.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %chan.value.bitcast)
+  ret void
+}
+
+; Function Attrs: argmemonly nofree nosync nounwind willreturn
+declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture) #1
+
+declare void @runtime.chanSend(%runtime.channel* dereferenceable_or_null(32), i8*, %runtime.channelBlockedList* dereferenceable_or_null(24), i8*)
+
+; Function Attrs: argmemonly nofree nosync nounwind willreturn
+declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture) #1
+
+; Function Attrs: nounwind
+define hidden void @main.chanIntRecv(%runtime.channel* dereferenceable_or_null(32) %ch, i8* %context) unnamed_addr #0 {
+entry:
+  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %chan.value = alloca i32, align 4
+  %chan.value.bitcast = bitcast i32* %chan.value to i8*
+  call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %chan.value.bitcast)
+  %chan.blockedList.bitcast = bitcast %runtime.channelBlockedList* %chan.blockedList to i8*
+  call void @llvm.lifetime.start.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  %0 = call i1 @runtime.chanRecv(%runtime.channel* %ch, i8* nonnull %chan.value.bitcast, %runtime.channelBlockedList* nonnull %chan.blockedList, i8* undef) #0
+  call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %chan.value.bitcast)
+  call void @llvm.lifetime.end.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  ret void
+}
+
+declare i1 @runtime.chanRecv(%runtime.channel* dereferenceable_or_null(32), i8*, %runtime.channelBlockedList* dereferenceable_or_null(24), i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.chanZeroSend(%runtime.channel* dereferenceable_or_null(32) %ch, i8* %context) unnamed_addr #0 {
+entry:
+  %complit = alloca {}, align 8
+  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %0 = bitcast {}* %complit to i8*
+  call void @runtime.trackPointer(i8* nonnull %0, i8* undef) #0
+  %chan.blockedList.bitcast = bitcast %runtime.channelBlockedList* %chan.blockedList to i8*
+  call void @llvm.lifetime.start.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  call void @runtime.chanSend(%runtime.channel* %ch, i8* null, %runtime.channelBlockedList* nonnull %chan.blockedList, i8* undef) #0
+  call void @llvm.lifetime.end.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.chanZeroRecv(%runtime.channel* dereferenceable_or_null(32) %ch, i8* %context) unnamed_addr #0 {
+entry:
+  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %chan.blockedList.bitcast = bitcast %runtime.channelBlockedList* %chan.blockedList to i8*
+  call void @llvm.lifetime.start.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  %0 = call i1 @runtime.chanRecv(%runtime.channel* %ch, i8* null, %runtime.channelBlockedList* nonnull %chan.blockedList, i8* undef) #0
+  call void @llvm.lifetime.end.p0i8(i64 24, i8* nonnull %chan.blockedList.bitcast)
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.selectZeroRecv(%runtime.channel* dereferenceable_or_null(32) %ch1, %runtime.channel* dereferenceable_or_null(32) %ch2, i8* %context) unnamed_addr #0 {
+entry:
+  %select.states.alloca = alloca [2 x %runtime.chanSelectState], align 8
+  %select.send.value = alloca i32, align 4
+  store i32 1, i32* %select.send.value, align 4
+  %select.states.alloca.bitcast = bitcast [2 x %runtime.chanSelectState]* %select.states.alloca to i8*
+  call void @llvm.lifetime.start.p0i8(i64 16, i8* nonnull %select.states.alloca.bitcast)
+  %.repack = getelementptr inbounds [2 x %runtime.chanSelectState], [2 x %runtime.chanSelectState]* %select.states.alloca, i32 0, i32 0, i32 0
+  store %runtime.channel* %ch1, %runtime.channel** %.repack, align 8
+  %.repack1 = getelementptr inbounds [2 x %runtime.chanSelectState], [2 x %runtime.chanSelectState]* %select.states.alloca, i32 0, i32 0, i32 1
+  %0 = bitcast i8** %.repack1 to i32**
+  store i32* %select.send.value, i32** %0, align 4
+  %.repack3 = getelementptr inbounds [2 x %runtime.chanSelectState], [2 x %runtime.chanSelectState]* %select.states.alloca, i32 0, i32 1, i32 0
+  store %runtime.channel* %ch2, %runtime.channel** %.repack3, align 8
+  %.repack4 = getelementptr inbounds [2 x %runtime.chanSelectState], [2 x %runtime.chanSelectState]* %select.states.alloca, i32 0, i32 1, i32 1
+  store i8* null, i8** %.repack4, align 4
+  %select.states = getelementptr inbounds [2 x %runtime.chanSelectState], [2 x %runtime.chanSelectState]* %select.states.alloca, i32 0, i32 0
+  %select.result = call { i32, i1 } @runtime.tryChanSelect(i8* undef, %runtime.chanSelectState* nonnull %select.states, i32 2, i32 2, i8* undef) #0
+  call void @llvm.lifetime.end.p0i8(i64 16, i8* nonnull %select.states.alloca.bitcast)
+  %1 = extractvalue { i32, i1 } %select.result, 0
+  %2 = icmp eq i32 %1, 0
+  br i1 %2, label %select.done, label %select.next
+
+select.done:                                      ; preds = %select.body, %select.next, %entry
+  ret void
+
+select.next:                                      ; preds = %entry
+  %3 = icmp eq i32 %1, 1
+  br i1 %3, label %select.body, label %select.done
+
+select.body:                                      ; preds = %select.next
+  br label %select.done
+}
+
+declare { i32, i1 } @runtime.tryChanSelect(i8*, %runtime.chanSelectState*, i32, i32, i8*)
+
+attributes #0 = { nounwind }
+attributes #1 = { argmemonly nofree nosync nounwind willreturn }

compiler/testdata/float.ll

@@ -1,16 +1,20 @@
 ; ModuleID = 'float.go'
 source_filename = "float.go"
-target datalayout = "e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128"
-target triple = "i686--linux"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-wasi"
 
 declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
 
-define hidden void @main.init(i8* %context, i8* %parentHandle) unnamed_addr {
+declare void @runtime.trackPointer(i8* nocapture readonly, i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.init(i8* %context) unnamed_addr #0 {
 entry:
   ret void
 }
 
-define hidden i32 @main.f32tou32(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i32 @main.f32tou32(float %v, i8* %context) unnamed_addr #0 {
 entry:
   %positive = fcmp oge float %v, 0.000000e+00
   %withinmax = fcmp ole float %v, 0x41EFFFFFC0000000
@@ -21,22 +25,26 @@ entry:
   ret i32 %0
 }
 
-define hidden float @main.maxu32f(i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden float @main.maxu32f(i8* %context) unnamed_addr #0 {
 entry:
   ret float 0x41F0000000000000
 }
 
-define hidden i32 @main.maxu32tof32(i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i32 @main.maxu32tof32(i8* %context) unnamed_addr #0 {
 entry:
   ret i32 -1
 }
 
-define hidden { i32, i32, i32, i32 } @main.inftoi32(i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden { i32, i32, i32, i32 } @main.inftoi32(i8* %context) unnamed_addr #0 {
 entry:
   ret { i32, i32, i32, i32 } { i32 -1, i32 0, i32 2147483647, i32 -2147483648 }
 }
 
-define hidden i32 @main.u32tof32tou32(i32 %v, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i32 @main.u32tof32tou32(i32 %v, i8* %context) unnamed_addr #0 {
 entry:
   %0 = uitofp i32 %v to float
   %withinmax = fcmp ole float %0, 0x41EFFFFFC0000000
@@ -45,7 +53,8 @@ entry:
   ret i32 %1
 }
 
-define hidden float @main.f32tou32tof32(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden float @main.f32tou32tof32(float %v, i8* %context) unnamed_addr #0 {
 entry:
   %positive = fcmp oge float %v, 0.000000e+00
   %withinmax = fcmp ole float %v, 0x41EFFFFFC0000000
@@ -57,7 +66,8 @@ entry:
   ret float %1
 }
 
-define hidden i8 @main.f32tou8(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i8 @main.f32tou8(float %v, i8* %context) unnamed_addr #0 {
 entry:
   %positive = fcmp oge float %v, 0.000000e+00
   %withinmax = fcmp ole float %v, 2.550000e+02
@@ -68,7 +78,8 @@ entry:
   ret i8 %0
 }
 
-define hidden i8 @main.f32toi8(float %v, i8* %context, i8* %parentHandle) unnamed_addr {
+; Function Attrs: nounwind
+define hidden i8 @main.f32toi8(float %v, i8* %context) unnamed_addr #0 {
 entry:
   %abovemin = fcmp oge float %v, -1.280000e+02
   %belowmax = fcmp ole float %v, 1.270000e+02
@@ -80,3 +91,5 @@ entry:
   %0 = select i1 %inbounds, i8 %normal, i8 %remapped
   ret i8 %0
 }
+
+attributes #0 = { nounwind }

compiler/testdata/func.go

@@ -0,0 +1,12 @@
+package main
+
+func foo(callback func(int)) {
+	callback(3)
+}
+
+func bar() {
+	foo(someFunc)
+}
+
+func someFunc(int) {
+}

compiler/testdata/func.ll

@@ -0,0 +1,47 @@
+; ModuleID = 'func.go'
+source_filename = "func.go"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-wasi"
+
+declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
+
+declare void @runtime.trackPointer(i8* nocapture readonly, i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.init(i8* %context) unnamed_addr #0 {
+entry:
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.foo(i8* %callback.context, void ()* %callback.funcptr, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = icmp eq void ()* %callback.funcptr, null
+  br i1 %0, label %fpcall.throw, label %fpcall.next
+
+fpcall.throw:                                     ; preds = %entry
+  call void @runtime.nilPanic(i8* undef) #0
+  unreachable
+
+fpcall.next:                                      ; preds = %entry
+  %1 = bitcast void ()* %callback.funcptr to void (i32, i8*)*
+  call void %1(i32 3, i8* %callback.context) #0
+  ret void
+}
+
+declare void @runtime.nilPanic(i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.bar(i8* %context) unnamed_addr #0 {
+entry:
+  call void @main.foo(i8* undef, void ()* bitcast (void (i32, i8*)* @main.someFunc to void ()*), i8* undef)
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.someFunc(i32 %arg0, i8* %context) unnamed_addr #0 {
+entry:
+  ret void
+}
+
+attributes #0 = { nounwind }

compiler/testdata/gc.go

@@ -0,0 +1,75 @@
+package main
+
+var (
+	scalar1 *byte
+	scalar2 *int32
+	scalar3 *int64
+	scalar4 *float32
+
+	array1 *[3]byte
+	array2 *[71]byte
+	array3 *[3]*byte
+
+	struct1 *struct{}
+	struct2 *struct {
+		x int
+		y int
+	}
+	struct3 *struct {
+		x *byte
+		y [60]uintptr
+		z *byte
+	}
+	struct4 *struct {
+		x *byte
+		y [61]uintptr
+	}
+
+	slice1 []byte
+	slice2 []*int
+	slice3 [][]byte
+)
+
+func newScalar() {
+	scalar1 = new(byte)
+	scalar2 = new(int32)
+	scalar3 = new(int64)
+	scalar4 = new(float32)
+}
+
+func newArray() {
+	array1 = new([3]byte)
+	array2 = new([71]byte)
+	array3 = new([3]*byte)
+}
+
+func newStruct() {
+	struct1 = new(struct{})
+	struct2 = new(struct {
+		x int
+		y int
+	})
+	struct3 = new(struct {
+		x *byte
+		y [60]uintptr
+		z *byte
+	})
+	struct4 = new(struct {
+		x *byte
+		y [61]uintptr
+	})
+}
+
+func newFuncValue() *func() {
+	return new(func())
+}
+
+func makeSlice() {
+	slice1 = make([]byte, 5)
+	slice2 = make([]*int, 5)
+	slice3 = make([][]byte, 5)
+}
+
+func makeInterface(v complex128) interface{} {
+	return v // always stored in an allocation
+}

compiler/testdata/gc.ll

@@ -0,0 +1,135 @@
+; ModuleID = 'gc.go'
+source_filename = "gc.go"
+target datalayout = "e-m:e-p:32:32-p10:8:8-p20:8:8-i64:64-n32:64-S128-ni:1:10:20"
+target triple = "wasm32-unknown-wasi"
+
+%runtime.typecodeID = type { %runtime.typecodeID*, i32, %runtime.interfaceMethodInfo*, %runtime.typecodeID*, i32 }
+%runtime.interfaceMethodInfo = type { i8*, i32 }
+%runtime._interface = type { i32, i8* }
+
+@main.scalar1 = hidden global i8* null, align 4
+@main.scalar2 = hidden global i32* null, align 4
+@main.scalar3 = hidden global i64* null, align 4
+@main.scalar4 = hidden global float* null, align 4
+@main.array1 = hidden global [3 x i8]* null, align 4
+@main.array2 = hidden global [71 x i8]* null, align 4
+@main.array3 = hidden global [3 x i8*]* null, align 4
+@main.struct1 = hidden global {}* null, align 4
+@main.struct2 = hidden global { i32, i32 }* null, align 4
+@main.struct3 = hidden global { i8*, [60 x i32], i8* }* null, align 4
+@main.struct4 = hidden global { i8*, [61 x i32] }* null, align 4
+@main.slice1 = hidden global { i8*, i32, i32 } zeroinitializer, align 8
+@main.slice2 = hidden global { i32**, i32, i32 } zeroinitializer, align 8
+@main.slice3 = hidden global { { i8*, i32, i32 }*, i32, i32 } zeroinitializer, align 8
+@"runtime/gc.layout:62-2000000000000001" = linkonce_odr unnamed_addr constant { i32, [8 x i8] } { i32 62, [8 x i8] c" \00\00\00\00\00\00\01" }
+@"runtime/gc.layout:62-0001" = linkonce_odr unnamed_addr constant { i32, [8 x i8] } { i32 62, [8 x i8] c"\00\00\00\00\00\00\00\01" }
+@"reflect/types.type:basic:complex128" = linkonce_odr constant %runtime.typecodeID { %runtime.typecodeID* null, i32 0, %runtime.interfaceMethodInfo* null, %runtime.typecodeID* @"reflect/types.type:pointer:basic:complex128", i32 0 }
+@"reflect/types.type:pointer:basic:complex128" = linkonce_odr constant %runtime.typecodeID { %runtime.typecodeID* @"reflect/types.type:basic:complex128", i32 0, %runtime.interfaceMethodInfo* null, %runtime.typecodeID* null, i32 0 }
+
+declare noalias nonnull i8* @runtime.alloc(i32, i8*, i8*)
+
+declare void @runtime.trackPointer(i8* nocapture readonly, i8*)
+
+; Function Attrs: nounwind
+define hidden void @main.init(i8* %context) unnamed_addr #0 {
+entry:
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.newScalar(i8* %context) unnamed_addr #0 {
+entry:
+  %new = call i8* @runtime.alloc(i32 1, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new, i8* undef) #0
+  store i8* %new, i8** @main.scalar1, align 4
+  %new1 = call i8* @runtime.alloc(i32 4, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new1, i8* undef) #0
+  store i8* %new1, i8** bitcast (i32** @main.scalar2 to i8**), align 4
+  %new2 = call i8* @runtime.alloc(i32 8, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new2, i8* undef) #0
+  store i8* %new2, i8** bitcast (i64** @main.scalar3 to i8**), align 4
+  %new3 = call i8* @runtime.alloc(i32 4, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new3, i8* undef) #0
+  store i8* %new3, i8** bitcast (float** @main.scalar4 to i8**), align 4
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.newArray(i8* %context) unnamed_addr #0 {
+entry:
+  %new = call i8* @runtime.alloc(i32 3, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new, i8* undef) #0
+  store i8* %new, i8** bitcast ([3 x i8]** @main.array1 to i8**), align 4
+  %new1 = call i8* @runtime.alloc(i32 71, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new1, i8* undef) #0
+  store i8* %new1, i8** bitcast ([71 x i8]** @main.array2 to i8**), align 4
+  %new2 = call i8* @runtime.alloc(i32 12, i8* nonnull inttoptr (i32 67 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new2, i8* undef) #0
+  store i8* %new2, i8** bitcast ([3 x i8*]** @main.array3 to i8**), align 4
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden void @main.newStruct(i8* %context) unnamed_addr #0 {
+entry:
+  %new = call i8* @runtime.alloc(i32 0, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new, i8* undef) #0
+  store i8* %new, i8** bitcast ({}** @main.struct1 to i8**), align 4
+  %new1 = call i8* @runtime.alloc(i32 8, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new1, i8* undef) #0
+  store i8* %new1, i8** bitcast ({ i32, i32 }** @main.struct2 to i8**), align 4
+  %new2 = call i8* @runtime.alloc(i32 248, i8* bitcast ({ i32, [8 x i8] }* @"runtime/gc.layout:62-2000000000000001" to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new2, i8* undef) #0
+  store i8* %new2, i8** bitcast ({ i8*, [60 x i32], i8* }** @main.struct3 to i8**), align 4
+  %new3 = call i8* @runtime.alloc(i32 248, i8* bitcast ({ i32, [8 x i8] }* @"runtime/gc.layout:62-0001" to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %new3, i8* undef) #0
+  store i8* %new3, i8** bitcast ({ i8*, [61 x i32] }** @main.struct4 to i8**), align 4
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden { i8*, void ()* }* @main.newFuncValue(i8* %context) unnamed_addr #0 {
+entry:
+  %new = call i8* @runtime.alloc(i32 8, i8* nonnull inttoptr (i32 197 to i8*), i8* undef) #0
+  %0 = bitcast i8* %new to { i8*, void ()* }*
+  call void @runtime.trackPointer(i8* nonnull %new, i8* undef) #0
+  ret { i8*, void ()* }* %0
+}
+
+; Function Attrs: nounwind
+define hidden void @main.makeSlice(i8* %context) unnamed_addr #0 {
+entry:
+  %makeslice = call i8* @runtime.alloc(i32 5, i8* nonnull inttoptr (i32 3 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %makeslice, i8* undef) #0
+  store i8* %makeslice, i8** getelementptr inbounds ({ i8*, i32, i32 }, { i8*, i32, i32 }* @main.slice1, i32 0, i32 0), align 8
+  store i32 5, i32* getelementptr inbounds ({ i8*, i32, i32 }, { i8*, i32, i32 }* @main.slice1, i32 0, i32 1), align 4
+  store i32 5, i32* getelementptr inbounds ({ i8*, i32, i32 }, { i8*, i32, i32 }* @main.slice1, i32 0, i32 2), align 8
+  %makeslice1 = call i8* @runtime.alloc(i32 20, i8* nonnull inttoptr (i32 67 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %makeslice1, i8* undef) #0
+  store i8* %makeslice1, i8** bitcast ({ i32**, i32, i32 }* @main.slice2 to i8**), align 8
+  store i32 5, i32* getelementptr inbounds ({ i32**, i32, i32 }, { i32**, i32, i32 }* @main.slice2, i32 0, i32 1), align 4
+  store i32 5, i32* getelementptr inbounds ({ i32**, i32, i32 }, { i32**, i32, i32 }* @main.slice2, i32 0, i32 2), align 8
+  %makeslice3 = call i8* @runtime.alloc(i32 60, i8* nonnull inttoptr (i32 71 to i8*), i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %makeslice3, i8* undef) #0
+  store i8* %makeslice3, i8** bitcast ({ { i8*, i32, i32 }*, i32, i32 }* @main.slice3 to i8**), align 8
+  store i32 5, i32* getelementptr inbounds ({ { i8*, i32, i32 }*, i32, i32 }, { { i8*, i32, i32 }*, i32, i32 }* @main.slice3, i32 0, i32 1), align 4
+  store i32 5, i32* getelementptr inbounds ({ { i8*, i32, i32 }*, i32, i32 }, { { i8*, i32, i32 }*, i32, i32 }* @main.slice3, i32 0, i32 2), align 8
+  ret void
+}
+
+; Function Attrs: nounwind
+define hidden %runtime._interface @main.makeInterface(double %v.r, double %v.i, i8* %context) unnamed_addr #0 {
+entry:
+  %0 = call i8* @runtime.alloc(i32 16, i8* null, i8* undef) #0
+  call void @runtime.trackPointer(i8* nonnull %0, i8* undef) #0
+  %.repack = bitcast i8* %0 to double*
+  store double %v.r, double* %.repack, align 8
+  %.repack1 = getelementptr inbounds i8, i8* %0, i32 8
+  %1 = bitcast i8* %.repack1 to double*
+  store double %v.i, double* %1, align 8
+  %2 = insertvalue %runtime._interface { i32 ptrtoint (%runtime.typecodeID* @"reflect/types.type:basic:complex128" to i32), i8* undef }, i8* %0, 1
+  call void @runtime.trackPointer(i8* nonnull %0, i8* undef) #0
+  ret %runtime._interface %2
+}
+
+attributes #0 = { nounwind }