release: update version to 0.36.0

Signed-off-by: deadprogram <ron@hybridgroup.com>
docs: update CHANGELOG for 0.36.0 release
2026-07-26 14:48:40 +00:00 · 2025-03-03 13:02:59 -08:00 · 2025-03-03 13:02:59 -08:00 · 2025-03-03 12:14:30 -08:00 · 2025-03-02 08:38:29 -03:00 · 2025-03-01 09:14:57 -08:00
324 changed files with 7378 additions and 3183 deletions
@@ -10,12 +10,12 @@ commands:
    steps:
      - restore_cache:
          keys:
-            - llvm-source-18-v1
+            - llvm-source-19-v1
      - run:
          name: "Fetch LLVM source"
          command: make llvm-source
      - save_cache:
-          key: llvm-source-18-v1
+          key: llvm-source-19-v1
          paths:
            - llvm-project/clang/lib/Headers
            - llvm-project/clang/include
@@ -109,12 +109,12 @@ jobs:
          # "make lint" fails before go 1.21 because internal/tools/go.mod specifies packages that require go 1.21
          fmt-check: false
    resource_class: large
-  test-llvm18-go123:
+  test-llvm19-go124:
    docker:
-      - image: golang:1.23-bullseye
+      - image: golang:1.24-bullseye
    steps:
      - test-linux:
-          llvm: "18"
+          llvm: "19"
    resource_class: large

 workflows:
@@ -123,5 +123,5 @@ workflows:
      # This tests our lowest supported versions of Go and LLVM, to make sure at
      # least the smoke tests still pass.
      - test-llvm15-go119
-      # This tests LLVM 18 support when linking against system libraries.
-      - test-llvm18-go123
+      # This tests LLVM 19 support when linking against system libraries.
+      - test-llvm19-go124
@@ -26,8 +26,6 @@ jobs:
            goarch: arm64
    runs-on: ${{ matrix.os }}
    steps:
-      - name: exit early
-        run: command-does-not-exist
      - name: Install Dependencies
        run: |
          HOMEBREW_NO_AUTO_UPDATE=1 brew install qemu binaryen
@@ -41,13 +39,13 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Restore LLVM source cache
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-${{ matrix.os }}-v2
+          key: llvm-source-19-${{ matrix.os }}-v1
          path: |
            llvm-project/clang/lib/Headers
            llvm-project/clang/include
@@ -72,7 +70,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-build
        with:
-          key: llvm-build-18-${{ matrix.os }}-v3
+          key: llvm-build-19-${{ matrix.os }}-v1
          path: llvm-build
      - name: Build LLVM
        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -128,10 +126,8 @@ jobs:
    runs-on: macos-latest
    strategy:
      matrix:
-        version: [16, 17, 18]
+        version: [16, 17, 18, 19]
    steps:
-      - name: exit early
-        run: command-does-not-exist
      - name: Set up Homebrew
        uses: Homebrew/actions/setup-homebrew@master
      - name: Fix Python symlinks
@@ -147,15 +143,15 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Build TinyGo (LLVM ${{ matrix.version }})
        run: go install -tags=llvm${{ matrix.version }}
      - name: Check binary
        run: tinygo version
      - name: Build TinyGo (default LLVM)
-        if: matrix.version == 18
+        if: matrix.version == 19
        run: go install
      - name: Check binary
-        if: matrix.version == 18
+        if: matrix.version == 19
        run: tinygo version
@@ -18,12 +18,10 @@ jobs:
    # statically linked binary.
    runs-on: ubuntu-latest
    container:
-      image: golang:1.23-alpine
+      image: golang:1.24-alpine
    outputs:
      version: ${{ steps.version.outputs.version }}
    steps:
-      - name: exit early
-        run: command-does-not-exist
      - name: Install apk dependencies
        # tar: needed for actions/cache@v4
        # git+openssh: needed for checkout (I think?)
@@ -50,7 +48,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-linux-alpine-v1
+          key: llvm-source-19-linux-alpine-v1
          path: |
            llvm-project/clang/lib/Headers
            llvm-project/clang/include
@@ -75,7 +73,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-build
        with:
-          key: llvm-build-18-linux-alpine-v2
+          key: llvm-build-19-linux-alpine-v1
          path: llvm-build
      - name: Build LLVM
        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -148,12 +146,12 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Install wasmtime
        uses: bytecodealliance/actions/wasmtime/setup@v1
        with:
-          version: "19.0.1"
+          version: "29.0.1"
      - name: Install wasm-tools
        uses: bytecodealliance/actions/wasm-tools/setup@v1
      - name: Download release artifact
@@ -173,8 +171,6 @@ jobs:
    # potential bugs.
    runs-on: ubuntu-latest
    steps:
-      - name: exit early
-        run: command-does-not-exist
      - name: Checkout
        uses: actions/checkout@v4
        with:
@@ -193,7 +189,7 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Install Node.js
        uses: actions/setup-node@v4
@@ -202,14 +198,14 @@ jobs:
      - name: Install wasmtime
        uses: bytecodealliance/actions/wasmtime/setup@v1
        with:
-          version: "19.0.1"
+          version: "29.0.1"
      - name: Setup `wasm-tools`
        uses: bytecodealliance/actions/wasm-tools/setup@v1
      - name: Restore LLVM source cache
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-linux-asserts-v1
+          key: llvm-source-19-linux-asserts-v1
          path: |
            llvm-project/clang/lib/Headers
            llvm-project/clang/include
@@ -234,7 +230,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-build
        with:
-          key: llvm-build-18-linux-asserts-v2
+          key: llvm-build-19-linux-asserts-v1
          path: llvm-build
      - name: Build LLVM
        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -301,7 +297,7 @@ jobs:
          - goarch: arm
            toolchain: arm-linux-gnueabihf
            libc: armhf
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04 # note: use the oldest image available! (see above)
    needs: build-linux
    steps:
      - name: Checkout
@@ -319,13 +315,13 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Restore LLVM source cache
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-linux-v1
+          key: llvm-source-19-linux-v1
          path: |
            llvm-project/clang/lib/Headers
            llvm-project/clang/include
@@ -350,7 +346,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-build
        with:
-          key: llvm-build-18-linux-${{ matrix.goarch }}-v2
+          key: llvm-build-19-linux-${{ matrix.goarch }}-v3
          path: llvm-build
      - name: Build LLVM
        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -35,8 +35,8 @@ jobs:
        uses: docker/metadata-action@v5
        with:
          images: |
-            tinygo/llvm-18
-            ghcr.io/${{ github.repository_owner }}/llvm-18
+            tinygo/llvm-19
+            ghcr.io/${{ github.repository_owner }}/llvm-19
          tags: |
            type=sha,format=long
            type=raw,value=latest
@@ -15,8 +15,6 @@ jobs:
  nix-test:
    runs-on: ubuntu-latest
    steps:
-      - name: exit early
-        run: command-does-not-exist
      - name: Uninstall system LLVM
        # Hack to work around issue where we still include system headers for
        # some reason.
@@ -31,7 +29,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-linux-nix-v1
+          key: llvm-source-19-linux-nix-v1
          path: |
            llvm-project/compiler-rt
      - name: Download LLVM source
@@ -2,11 +2,11 @@
 # still works after checking out the dev branch (that is, when going from LLVM
 # 16 to LLVM 17 for example, both Clang 16 and Clang 17 are installed).

-echo 'deb https://apt.llvm.org/noble/ llvm-toolchain-noble-18 main' | sudo tee /etc/apt/sources.list.d/llvm.list
+echo 'deb https://apt.llvm.org/noble/ llvm-toolchain-noble-19 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 -y \
-    llvm-18-dev \
-    clang-18 \
-    libclang-18-dev \
-    lld-18
+    llvm-19-dev \
+    clang-19 \
+    libclang-19-dev \
+    lld-19
@@ -15,8 +15,6 @@ jobs:
    permissions:
      pull-requests: write
    steps:
-      - name: exit early
-        run: command-does-not-exist
      # Prepare, install tools
      - name: Add GOBIN to $PATH
        run: |
@@ -32,7 +30,7 @@ jobs:
        uses: actions/cache@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-sizediff-v1
+          key: llvm-source-19-sizediff-v1
          path: |
            llvm-project/compiler-rt
      - name: Download LLVM source
@@ -23,35 +23,31 @@ jobs:
          minimum-size: 8GB
          maximum-size: 24GB
          disk-root: "C:"
-      #- uses: brechtm/setup-scoop@v2
-      #  with:
-      #    scoop_update: 'false'
-      #- name: Install Dependencies
-      #  shell: bash
-      #  run: |
-      #    scoop install ninja binaryen
+      - uses: brechtm/setup-scoop@v2
+        with:
+          scoop_update: 'false'
+      - name: Install Dependencies
+        shell: bash
+        run: |
+          scoop install ninja binaryen
      - name: Checkout
        uses: actions/checkout@v4
-      - name: submodules
-        shell: bash
-        run: git submodule update --init lib/mingw-w64
+        with:
+          submodules: true
      - name: Extract TinyGo version
        id: version
        shell: bash
        run: ./.github/workflows/tinygo-extract-version.sh | tee -a "$GITHUB_OUTPUT"
-      - name: command
-        shell: bash
-        run: go env
-      #- name: Install Go
-      #  uses: actions/setup-go@v5
-      #  with:
-      #    go-version: '1.23'
-      #    cache: true
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.24'
+          cache: true
      - name: Restore cached LLVM source
        uses: actions/cache/restore@v4
        id: cache-llvm-source
        with:
-          key: llvm-source-18-windows-v1
+          key: llvm-source-19-windows-v1
          path: |
            llvm-project/clang/lib/Headers
            llvm-project/clang/include
@@ -76,7 +72,7 @@ jobs:
        uses: actions/cache/restore@v4
        id: cache-llvm-build
        with:
-          key: llvm-build-18-windows-v2
+          key: llvm-build-19-windows-v1
          path: llvm-build
      - name: Build LLVM
        if: steps.cache-llvm-build.outputs.cache-hit != 'true'
@@ -95,25 +91,6 @@ jobs:
        with:
          key: ${{ steps.cache-llvm-build.outputs.cache-primary-key }}
          path: llvm-build
-      - name: Restore Go cache
-        uses: actions/cache/restore@v4
-        with:
-          key: go-cache-v2
-          path: |
-            C:/Users/runneradmin/AppData/Local/go-build
-            C:/Users/runneradmin/go/pkg/mod
-      - name: Test TinyGo
-        shell: bash
-        run: make test GOTESTFLAGS="-short -run=TestBuild -v"
-      - name: Save Go cache
-        uses: actions/cache/save@v4
-        with:
-          key: go-cache-v2
-          path: |
-            C:/Users/runneradmin/AppData/Local/go-build
-            C:/Users/runneradmin/go/pkg/mod
-      - name: exit
-        run: command-does-not-exist
      - name: Cache wasi-libc sysroot
        uses: actions/cache@v4
        id: cache-wasi-libc
@@ -123,11 +100,21 @@ jobs:
      - name: Build wasi-libc
        if: steps.cache-wasi-libc.outputs.cache-hit != 'true'
        run: make wasi-libc
+      - name: Cache Go cache
+        uses: actions/cache@v4
+        with:
+          key: go-cache-windows-v1-${{ hashFiles('go.mod') }}
+          path: |
+            C:/Users/runneradmin/AppData/Local/go-build
+            C:/Users/runneradmin/go/pkg/mod
      - name: Install wasmtime
        run: |
-          scoop install wasmtime@14.0.4
+          scoop install wasmtime@29.0.1
      - name: make gen-device
        run: make -j3 gen-device
+      - name: Test TinyGo
+        shell: bash
+        run: make test GOTESTFLAGS="-short"
      - name: Build TinyGo release tarball
        shell: bash
        run: make build/release -j4
@@ -169,7 +156,7 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Download TinyGo build
        uses: actions/download-artifact@v4
@@ -199,7 +186,7 @@ jobs:
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Download TinyGo build
        uses: actions/download-artifact@v4
@@ -229,13 +216,13 @@ jobs:
      - name: Install Dependencies
        shell: bash
        run: |
-          scoop install binaryen && scoop install wasmtime@14.0.4
+          scoop install binaryen && scoop install wasmtime@29.0.1
      - name: Checkout
        uses: actions/checkout@v4
      - name: Install Go
        uses: actions/setup-go@v5
        with:
-          go-version: '1.23'
+          go-version: '1.24'
          cache: true
      - name: Download TinyGo build
        uses: actions/download-artifact@v4
@@ -37,5 +37,9 @@ test.exe
 test.gba
 test.hex
 test.nro
+test.uf2
 test.wasm
 wasm.wasm
+
+*.uf2
+*.elf
@@ -1,3 +1,140 @@
+0.36.0
+---
+* **general**
+  - add initial Go 1.24 support
+  - add support for LLVM 19
+  - update license for 2025
+  - make small corrections for README regarding wasm
+  - use GOOS and GOARCH for building wasm simulated boards
+  - only infer target for wasm when GOOS and GOARCH are set correctly, not just based on file extension
+  - add test-corpus-wasip2
+  - use older image for cross-compiling builds
+  - update Linux builds to run on ubuntu-latest since 20.04 is being retired
+  - ensure build output directory is created
+  - add NoSandbox flag to chrome headless that is run during WASM tests, since this is now required for Ubuntu 23+ and we are using Ubuntu 24+ when running Github Actions
+  - update wasmtime used for CI to 29.0.1 to fix issue with install during CI tests
+  - update to use `Get-CimInstance` as `wmic` is being deprecated on WIndows
+  - remove unnecessary executable permissions
+  - `goenv`: update to new v0.36.0 development version
+* **compiler**
+  - `builder`: fix parsing of external ld.lld error messages
+  - `cgo`: mangle identifier names
+  - `interp`: correctly mark functions as modifying memory
+  - add buildmode=wasi-legacy to support existing base of users who expected the older behavior for wasi modules to not return an exit code as if they were reactors
+* **standard library**
+  - `crypto/tls`: add Dialer.DialContext() to fix websocket client
+  - `crypto/tls`: add VersionTLS constants and VersionName(version uint16) method that turns it into a string, copied from big go
+  - `internal/syscall/unix`: use our own version of this package
+  - `machine`: replace hard-coded cpu frequencies on rp2xxx
+  - `machine`: bump rp2350 CPUFrequency to 150 MHz
+  - `machine`: compute rp2 clock dividers from crystal and target frequency
+  - `machine`: remove bytes package dependency in flash code
+  - `machine/usb/descriptor`: avoid bytes package
+  - `net`: update to latest submodule with httptest subpackage and ResolveIPAddress implementation
+  - `os`: add File.Chdir support
+  - `os`: implement stub Chdir for non-OS systems
+  - `os/file`: add file.Chmod
+  - `reflect`: implement Value.Equal
+  - `runtime`: add FIPS helper functions
+  - `runtime`: manually initialize xorshift state
+  - `sync`: move Mutex to internal/task
+  - `syscall`: add wasip1 RandomGet
+  - `testing`: add Chdir
+  - `wasip2`: add stubs to get internal/syscall/unix to work
+* **fixes**
+  - correctly handle calls for GetRNG() when being made from nrf devices with SoftDevice enabled
+  - fix stm32f103 ADC
+  - `wasm`: correctly handle id lookup for finalizeRef call
+  - `wasm`: avoid total failure on wasm finalizer call
+  - `wasm`: convert offset as signed int into unsigned int in syscall/js.stringVal in wasm_exec.js
+* **targets**
+  - rp2350: add pll generalized solution; fix ADC handles; pwm period fix
+  - rp2350: extending support to include the rp2350b
+  - rp2350: cleanup: unexport internal USB and clock package variable, consts and types
+  - nrf: make ADC resolution changeable
+  - turn on GC for TKey1 device, since it does in fact work
+  - match Pico2 stack size to Pico
+* **boards**
+  - add support for Pimoroni Pico Plus2
+  - add target for pico2-w board
+  - add comboat_fw tag for elecrow W5 boards with Combo-AT Wifi firmware
+  - add support for Elecrow Pico rp2350 W5 boards
+  - add support for Elecrow Pico rp2040 W5 boards
+  - add support for NRF51 HW-651
+  - add support for esp32c3-supermini
+  - add support for waveshare-rp2040-tiny
+* **examples**
+  - add naive debouncing for pininterrupt example
+
+
+0.35.0
+---
+* **general**
+  - update cmsis-svd library
+  - use default UART settings in the echo example
+  - `goenv`: also show git hash with custom build of TinyGo
+  - `goenv`: support parsing development versions of Go
+  - `main`: parse extldflags early so we can report the error message
+* **compiler**
+  - `builder`: whitelist temporary directory env var for Clang invocation to fix Windows bug
+  - `builder`: fix cache paths in `-size=full` output
+  - `builder`: work around incorrectly escaped DWARF paths on Windows (Clang bug)
+  - `builder`: fix wasi-libc path names on Windows with `-size=full`
+  - `builder`: write HTML size report
+  - `cgo`: support C identifiers only referred to from within macros
+  - `cgo`: support function-like macros
+  - `cgo`: support errno value as second return parameter
+  - `cgo`: add support for `#cgo noescape` lines
+  - `compiler`: fix bug in interrupt lowering
+  - `compiler`: allow panic directly in `defer`
+  - `compiler`: fix wasmimport -> wasmexport in error message
+  - `compiler`: support `//go:noescape` pragma
+  - `compiler`: report error instead of crashing when instantiating a generic function without body
+  - `interp`: align created globals
+* **standard library**
+  - `machine`: modify i2s interface/implementation to better match specification
+  - `os`: implement `StartProcess`
+  - `reflect`: add `Value.Clear`
+  - `reflect`: add interface support to `NumMethods`
+  - `reflect`: fix `AssignableTo` for named + non-named types
+  - `reflect`: implement `CanConvert`
+  - `reflect`: handle more cases in `Convert`
+  - `reflect`: fix Copy of non-pointer array with size > 64bits
+  - `runtime`: don't call sleepTicks with a negative duration
+  - `runtime`: optimize GC scanning (findHead)
+  - `runtime`: move constants into shared package
+  - `runtime`: add `runtime.fcntl` function for internal/syscall/unix
+  - `runtime`: heapptr only needs to be initialized once
+  - `runtime`: refactor scheduler (this fixes a few bugs with `-scheduler=none`)
+  - `runtime`: rewrite channel implementation to be smaller and more flexible
+  - `runtime`: use `SA_RESTART` when registering a signal for os/signal
+  - `runtime`: implement race-free signals using futexes
+  - `runtime`: run deferred functions in `Goexit`
+  - `runtime`: remove `Cond` which seems to be unused
+  - `runtime`: properly handle unix read on directory
+  - `runtime/trace`: stub all public methods
+  - `sync`: don't use volatile in `Mutex`
+  - `sync`: implement `WaitGroup` using a (pseudo)futex
+  - `sync`: make `Cond` parallelism-safe
+  - `syscall`: use wasi-libc tables for wasm/js target
+* **targets**
+  - `mips`: fix a bug when scanning the stack
+  - `nintendoswitch`: get this target to compile again
+  - `rp2350`: add support for the new RP2350
+  - `rp2040/rp2350` : make I2C implementation shared for rp2040/rp2350
+  - `rp2040/rp2350` : make SPI implementation shared for rp2040/rp2350
+  - `rp2040/rp2350` : make RNG implementation shared for rp2040/rp2350
+  - `wasm`: revise and simplify wasmtime argument handling
+  - `wasm`: support `//go:wasmexport` functions after a call to `time.Sleep`
+  - `wasm`: correctly return from run() in wasm_exec.js
+  - `wasm`: call process.exit() when go.run() returns
+  - `windows`: don't return, exit via exit(0) instead to flush stdout buffer
+* **boards**
+  - add support for the Tillitis TKey
+  - add support for the Raspberry Pi Pico2 (based on the RP2040)
+  - add support for Pimoroni Tiny2350
+
+
 0.34.0
 ---
 * **general**
@@ -1,5 +1,5 @@
 # tinygo-llvm stage obtains the llvm source for TinyGo
-FROM golang:1.23 AS tinygo-llvm
+FROM golang:1.24 AS tinygo-llvm

 RUN apt-get update && \
    apt-get install -y apt-utils make cmake clang-15 ninja-build && \
@@ -33,7 +33,7 @@ RUN cd /tinygo/ && \

 # tinygo-compiler copies the compiler build over to a base Go container (without
 # all the build tools etc).
-FROM golang:1.23 AS tinygo-compiler
+FROM golang:1.24 AS tinygo-compiler

 # Copy tinygo build.
 COPY --from=tinygo-compiler-build /tinygo/build/release/tinygo /tinygo
@@ -10,7 +10,7 @@ LLD_SRC ?= $(LLVM_PROJECTDIR)/lld

 # Try to autodetect LLVM build tools.
 # Versions are listed here in descending priority order.
-LLVM_VERSIONS = 18 17 16 15
+LLVM_VERSIONS = 19 18 17 16 15
 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)
@@ -147,7 +147,7 @@ endif
 MD5SUM ?= md5sum

 # Libraries that should be linked in for the statically linked Clang.
-CLANG_LIB_NAMES = clangAnalysis clangAPINotes clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangExtractAPI clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangSupport clangTooling clangToolingASTDiff clangToolingCore clangToolingInclusions
+CLANG_LIB_NAMES = clangAnalysis clangAPINotes clangAST clangASTMatchers clangBasic clangCodeGen clangCrossTU clangDriver clangDynamicASTMatchers clangEdit clangExtractAPI clangFormat clangFrontend clangFrontendTool clangHandleCXX clangHandleLLVM clangIndex clangInstallAPI clangLex clangParse clangRewrite clangRewriteFrontend clangSema clangSerialization clangSupport 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.
@@ -191,7 +191,7 @@ gen-device: gen-device-stm32
 endif

 gen-device-avr:
-	#@if [ ! -e lib/avr/README.md ]; then echo "Submodules have not been downloaded. Please download them using:\n  git submodule update --init"; exit 1; fi
+	@if [ ! -e lib/avr/README.md ]; then echo "Submodules have not been downloaded. Please download them using:\n  git submodule update --init"; exit 1; fi
 	$(GO) build -o ./build/gen-device-avr ./tools/gen-device-avr/
 	./build/gen-device-avr lib/avr/packs/atmega src/device/avr/
 	./build/gen-device-avr lib/avr/packs/tiny src/device/avr/
@@ -238,7 +238,7 @@ gen-device-renesas: build/gen-device-svd
 	GO111MODULE=off $(GO) fmt ./src/device/renesas

 $(LLVM_PROJECTDIR)/llvm:
-	git clone -b tinygo_xtensa_release_18.1.2 --depth=1 https://github.com/tinygo-org/llvm-project $(LLVM_PROJECTDIR)
+	git clone -b xtensa_release_19.1.2 --depth=1 https://github.com/espressif/llvm-project $(LLVM_PROJECTDIR)
 llvm-source: $(LLVM_PROJECTDIR)/llvm ## Get LLVM sources

 # Configure LLVM.
@@ -263,7 +263,7 @@ endif
 .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
+	@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 && $(MAKE) -j4 EXTRA_CFLAGS="-O2 -g -DNDEBUG -mnontrapping-fptoint -msign-ext" MALLOC_IMPL=none CC="$(CLANG)" AR=$(LLVM_AR) NM=$(LLVM_NM)

 # Generate WASI syscall bindings
@@ -292,8 +292,8 @@ endif
 tinygo: ## Build the TinyGo compiler
 	@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)" $(GOENVFLAGS) $(GO) build -buildmode exe -o build/tinygo$(EXE) -tags "byollvm osusergo" .
-test: #wasi-libc check-nodejs-version
-	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=1h -race -buildmode exe -tags "byollvm osusergo" .
+test: wasi-libc check-nodejs-version
+	CGO_CPPFLAGS="$(CGO_CPPFLAGS)" CGO_CXXFLAGS="$(CGO_CXXFLAGS)" CGO_LDFLAGS="$(CGO_LDFLAGS)" $(GO) test $(GOTESTFLAGS) -timeout=1h -buildmode exe -tags "byollvm osusergo" $(GOTESTPKGS)

 # Standard library packages that pass tests on darwin, linux, wasi, and windows, but take over a minute in wasi
 TEST_PACKAGES_SLOW = \
@@ -309,11 +309,9 @@ TEST_PACKAGES_FAST = \
 	container/heap \
 	container/list \
 	container/ring \
-	crypto/des \
 	crypto/ecdsa \
 	crypto/elliptic \
 	crypto/md5 \
-	crypto/rc4 \
 	crypto/sha1 \
 	crypto/sha256 \
 	crypto/sha512 \
@@ -355,17 +353,11 @@ TEST_PACKAGES_FAST = \
 	unique \
 	$(nil)

-# Assume this will go away before Go2, so only check minor version.
-ifeq ($(filter $(shell $(GO) env GOVERSION | cut -f 2 -d.), 16 17 18), )
-TEST_PACKAGES_FAST += crypto/internal/nistec/fiat
-else
-TEST_PACKAGES_FAST += crypto/elliptic/internal/fiat
-endif
-
 # archive/zip requires os.ReadAt, which is not yet supported on windows
 # bytes requires mmap
 # compress/flate appears to hang on wasi
 # crypto/aes fails on wasi, needs panic()/recover()
+# crypto/des fails on wasi, needs panic()/recover()
 # crypto/hmac fails on wasi, it exits with a "slice out of range" panic
 # debug/plan9obj requires os.ReadAt, which is not yet supported on windows
 # image requires recover(), which is not yet supported on wasi
@@ -386,6 +378,7 @@ TEST_PACKAGES_LINUX := \
 	archive/zip \
 	compress/flate \
 	crypto/aes \
+	crypto/des \
 	crypto/hmac \
 	debug/dwarf \
 	debug/plan9obj \
@@ -405,10 +398,11 @@ TEST_PACKAGES_LINUX := \

 TEST_PACKAGES_DARWIN := $(TEST_PACKAGES_LINUX)

+# os/user requires t.Skip() support
 TEST_PACKAGES_WINDOWS := \
 	compress/flate \
+	crypto/des \
 	crypto/hmac \
-	os/user \
 	strconv \
 	text/template/parse \
 	$(nil)
@@ -497,6 +491,8 @@ test-corpus-fast:
 	CGO_CPPFLAGS="$(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 $(GOTESTFLAGS) -timeout=1h -buildmode exe -tags byollvm -run TestCorpus . -corpus=testdata/corpus.yaml -target=wasip1
+test-corpus-wasip2: wasi-libc
+	CGO_CPPFLAGS="$(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=wasip2

 tinygo-baremetal:
 	# Regression tests that run on a baremetal target and don't fit in either main_test.go or smoketest.
@@ -523,6 +519,8 @@ smoketest: testchdir
 	# regression test for #2563
 	cd tests/os/smoke && $(TINYGO) test -c -target=pybadge && rm smoke.test
 	# test all examples (except pwm)
+	$(TINYGO) build -size short -o test.hex -target=pga2350             examples/echo
+	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/blinky1
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040            examples/adc
@@ -571,21 +569,21 @@ smoketest: testchdir
 	@$(MD5SUM) test.hex
 	# test simulated boards on play.tinygo.org
 ifneq ($(WASM), 0)
-	$(TINYGO) build -size short -o test.wasm -tags=arduino              examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=arduino              examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=hifive1b             examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=hifive1b             examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=reelboard            examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=reelboard            examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=microbit             examples/microbit-blink
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=microbit             examples/microbit-blink
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=circuitplay_express  examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=circuitplay_express  examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=circuitplay_bluefruit examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=circuitplay_bluefruit examples/blinky1
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=mch2022              examples/machinetest
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=mch2022              examples/machinetest
 	@$(MD5SUM) test.wasm
-	$(TINYGO) build -size short -o test.wasm -tags=gopher_badge         examples/blinky1
+	GOOS=js GOARCH=wasm $(TINYGO) build -size short -o test.wasm -tags=gopher_badge         examples/blinky1
 	@$(MD5SUM) test.wasm
 endif
 	# test all targets/boards
@@ -741,6 +739,14 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=thumby              examples/echo
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=pico2               examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=tiny2350            examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=pico-plus2          examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=waveshare-rp2040-tiny examples/echo
+	@$(MD5SUM) test.hex
 	# test pwm
 	$(TINYGO) build -size short -o test.hex -target=itsybitsy-m0        examples/pwm
 	@$(MD5SUM) test.hex
@@ -822,6 +828,8 @@ endif
 ifneq ($(XTENSA), 0)
 	$(TINYGO) build -size short -o test.bin -target=esp32-mini32      	examples/blinky1
 	@$(MD5SUM) test.bin
+	$(TINYGO) build -size short -o test.bin -target=esp32c3-supermini   examples/blinky1
+	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target=nodemcu             examples/blinky1
 	@$(MD5SUM) test.bin
 	$(TINYGO) build -size short -o test.bin -target m5stack-core2       examples/machinetest
@@ -853,6 +861,16 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=maixbit             examples/blinky1
 	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=tkey                examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=elecrow-rp2040      examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=elecrow-rp2350      examples/blinky1
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=hw-651              examples/machinetest
+	@$(MD5SUM) test.hex
+	$(TINYGO) build -size short -o test.hex -target=hw-651-s110v8       examples/machinetest
+	@$(MD5SUM) test.hex	
 ifneq ($(WASM), 0)
 	$(TINYGO) build -size short -o wasm.wasm -target=wasm               examples/wasm/export
 	$(TINYGO) build -size short -o wasm.wasm -target=wasm               examples/wasm/main
@@ -867,7 +885,7 @@ endif
 	@$(MD5SUM) test.hex
 	$(TINYGO) build -size short -o test.hex -target=pca10040 -serial=rtt examples/echo
 	@$(MD5SUM) test.hex
-	$(TINYGO) build             -o test.nro -target=nintendoswitch      examples/serial
+	$(TINYGO) build             -o test.nro -target=nintendoswitch      examples/echo2
 	@$(MD5SUM) test.nro
 	$(TINYGO) build -size short -o test.hex -target=pca10040 -opt=0     ./testdata/stdlib.go
 	@$(MD5SUM) test.hex
@@ -935,6 +953,7 @@ endif
 	@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/math            build/release/tinygo/lib/musl/src
+	@cp -rp lib/musl/src/misc            build/release/tinygo/lib/musl/src
 	@cp -rp lib/musl/src/multibyte       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
@@ -1,7 +1,7 @@
-Copyright (c) 2018-2023 The TinyGo Authors. All rights reserved.
+Copyright (c) 2018-2025 The TinyGo Authors. All rights reserved.

 TinyGo includes portions of the Go standard library.
-Copyright (c) 2009-2023 The Go Authors. All rights reserved.
+Copyright (c) 2009-2024 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.
@@ -48,20 +48,22 @@ Here is a small TinyGo program for use by a WASI host application:
 ```go
 package main

-//go:wasm-module yourmodulename
-//export add
+//go:wasmexport add
 func add(x, y uint32) uint32 {
 	return x + y
 }
-
-// main is required for the `wasip1` target, even if it isn't used.
-func main() {}
 ```

-This compiles the above TinyGo program for use on any WASI runtime:
+This compiles the above TinyGo program for use on any WASI Preview 1 runtime:

 ```shell
-tinygo build -o main.wasm -target=wasip1 main.go
+tinygo build -buildmode=c-shared -o add.wasm -target=wasip1 add.go
+```
+
+You can also use the same syntax as Go 1.24+:
+
+```shell
+GOARCH=wasip1 GOOS=wasm tinygo build -buildmode=c-shared -o add.wasm add.go
 ```

 ## Installation
@@ -61,6 +61,10 @@ type BuildResult struct {
 	// correctly printing test results: the import path isn't always the same as
 	// the path listed on the command line.
 	ImportPath string
+
+	// Map from path to package name. It is needed to attribute binary size to
+	// the right Go package.
+	PackagePathMap map[string]string
 }

 // packageAction is the struct that is serialized to JSON and hashed, to work as
@@ -242,6 +246,12 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 		return result, err
 	}

+	// Store which filesystem paths map to which package name.
+	result.PackagePathMap = make(map[string]string, len(lprogram.Packages))
+	for _, pkg := range lprogram.Sorted() {
+		result.PackagePathMap[pkg.OriginalDir()] = pkg.Pkg.Path()
+	}
+
 	// Create the *ssa.Program. This does not yet build the entire SSA of the
 	// program so it's pretty fast and doesn't need to be parallelized.
 	program := lprogram.LoadSSA()
@@ -594,6 +604,11 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 		},
 	}

+	// Create the output directory, if needed
+	if err := os.MkdirAll(filepath.Dir(outpath), 0777); err != nil {
+		return result, err
+	}
+
 	// Check whether we only need to create an object file.
 	// If so, we don't need to link anything and will be finished quickly.
 	outext := filepath.Ext(outpath)
@@ -657,6 +672,16 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 		ldflags = append(ldflags, "--no-entry")
 	}

+	if config.Options.BuildMode == "wasi-legacy" {
+		if !strings.HasPrefix(config.Triple(), "wasm32-") {
+			return result, fmt.Errorf("buildmode wasi-legacy is only supported on wasm")
+		}
+
+		if config.Options.Scheduler != "none" {
+			return result, fmt.Errorf("buildmode wasi-legacy only supports scheduler=none")
+		}
+	}
+
 	// Add compiler-rt dependency if needed. Usually this is a simple load from
 	// a cache.
 	if config.Target.RTLib == "compiler-rt" {
@@ -690,7 +715,7 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 	for _, pkg := range lprogram.Sorted() {
 		pkg := pkg
 		for _, filename := range pkg.CFiles {
-			abspath := filepath.Join(pkg.Dir, filename)
+			abspath := filepath.Join(pkg.OriginalDir(), filename)
 			job := &compileJob{
 				description: "compile CGo file " + abspath,
 				run: func(job *compileJob) error {
@@ -812,6 +837,12 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 					return fmt.Errorf("could not modify stack sizes: %w", err)
 				}
 			}
+
+			// Apply patches of bootloader in the order they appear.
+			if len(config.Target.BootPatches) > 0 {
+				err = applyPatches(result.Executable, config.Target.BootPatches)
+			}
+
 			if config.RP2040BootPatch() {
 				// Patch the second stage bootloader CRC into the .boot2 section
 				err = patchRP2040BootCRC(result.Executable)
@@ -915,19 +946,16 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 			}

 			// Print code size if requested.
-			if config.Options.PrintSizes == "short" || config.Options.PrintSizes == "full" {
-				packagePathMap := make(map[string]string, len(lprogram.Packages))
-				for _, pkg := range lprogram.Sorted() {
-					packagePathMap[pkg.OriginalDir()] = pkg.Pkg.Path()
-				}
-				sizes, err := loadProgramSize(result.Executable, packagePathMap)
+			if config.Options.PrintSizes != "" {
+				sizes, err := loadProgramSize(result.Executable, result.PackagePathMap)
 				if err != nil {
 					return err
 				}
-				if config.Options.PrintSizes == "short" {
+				switch config.Options.PrintSizes {
+				case "short":
 					fmt.Printf("   code    data     bss |   flash     ram\n")
 					fmt.Printf("%7d %7d %7d | %7d %7d\n", sizes.Code+sizes.ROData, sizes.Data, sizes.BSS, sizes.Flash(), sizes.RAM())
-				} else {
+				case "full":
 					if !config.Debug() {
 						fmt.Println("warning: data incomplete, remove the -no-debug flag for more detail")
 					}
@@ -939,6 +967,13 @@ func Build(pkgName, outpath, tmpdir string, config *compileopts.Config) (BuildRe
 					}
 					fmt.Printf("------------------------------- | --------------- | -------\n")
 					fmt.Printf("%7d %7d %7d %7d | %7d %7d | total\n", sizes.Code, sizes.ROData, sizes.Data, sizes.BSS, sizes.Code+sizes.ROData+sizes.Data, sizes.Data+sizes.BSS)
+				case "html":
+					const filename = "size-report.html"
+					err := writeSizeReport(sizes, filename, pkgName)
+					if err != nil {
+						return err
+					}
+					fmt.Println("Wrote size report to", filename)
 				}
 			}

@@ -1428,6 +1463,23 @@ func printStacks(calculatedStacks []string, stackSizes map[string]functionStackS
 	}
 }

+func applyPatches(executable string, bootPatches []string) (err error) {
+	for _, patch := range bootPatches {
+		switch patch {
+		case "rp2040":
+			err = patchRP2040BootCRC(executable)
+		// case "rp2350":
+		// 	err = patchRP2350BootIMAGE_DEF(executable)
+		default:
+			err = errors.New("undefined boot patch name")
+		}
+		if err != nil {
+			return fmt.Errorf("apply boot patch %q: %w", patch, err)
+		}
+	}
+	return nil
+}
+
 // RP2040 second stage bootloader CRC32 calculation
 //
 // Spec: https://datasheets.raspberrypi.org/rp2040/rp2040-datasheet.pdf
@@ -1439,7 +1491,7 @@ func patchRP2040BootCRC(executable string) error {
 	}

 	if len(bytes) != 256 {
-		return fmt.Errorf("rp2040 .boot2 section must be exactly 256 bytes")
+		return fmt.Errorf("rp2040 .boot2 section must be exactly 256 bytes, got %d", len(bytes))
 	}

 	// From the 'official' RP2040 checksum script:
@@ -1478,3 +1530,10 @@ func lock(path string) func() {

 	return func() { flock.Close() }
 }
+
+func b2u8(b bool) uint8 {
+	if b {
+		return 1
+	}
+	return 0
+}
@@ -33,6 +33,7 @@ func TestClangAttributes(t *testing.T) {
 		"k210",
 		"nintendoswitch",
 		"riscv-qemu",
+		"tkey",
 		"wasip1",
 		"wasip2",
 		"wasm",
@@ -68,7 +69,6 @@ func TestClangAttributes(t *testing.T) {
 		{GOOS: "darwin", GOARCH: "arm64"},
 		{GOOS: "windows", GOARCH: "amd64"},
 		{GOOS: "windows", GOARCH: "arm64"},
-		{GOOS: "wasip1", GOARCH: "wasm"},
 	} {
 		name := "GOOS=" + options.GOOS + ",GOARCH=" + options.GOARCH
 		if options.GOARCH == "arm" {
@@ -145,6 +145,7 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
  }

  Opts.RelaxELFRelocations = !Args.hasArg(OPT_mrelax_relocations_no);
+  Opts.SSE2AVX = Args.hasArg(OPT_msse2avx);
  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);
@@ -234,6 +235,7 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,

  Opts.EmitCompactUnwindNonCanonical =
      Args.hasArg(OPT_femit_compact_unwind_non_canonical);
+  Opts.Crel = Args.hasArg(OPT_crel);

  Opts.AsSecureLogFile = Args.getLastArgValue(OPT_as_secure_log_file);

@@ -287,8 +289,14 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
  assert(MRI && "Unable to create target register info!");

  MCTargetOptions MCOptions;
+  MCOptions.MCRelaxAll = Opts.RelaxAll;
  MCOptions.EmitDwarfUnwind = Opts.EmitDwarfUnwind;
  MCOptions.EmitCompactUnwindNonCanonical = Opts.EmitCompactUnwindNonCanonical;
+  MCOptions.MCSaveTempLabels = Opts.SaveTemporaryLabels;
+  MCOptions.Crel = Opts.Crel;
+  MCOptions.X86RelaxRelocations = Opts.RelaxELFRelocations;
+  MCOptions.X86Sse2Avx = Opts.SSE2AVX;
+  MCOptions.CompressDebugSections = Opts.CompressDebugSections;
  MCOptions.AsSecureLogFile = Opts.AsSecureLogFile;

  std::unique_ptr<MCAsmInfo> MAI(
@@ -297,9 +305,7 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,

  // Ensure MCAsmInfo initialization occurs before any use, otherwise sections
  // may be created with a combination of default and explicit settings.
-  MAI->setCompressDebugSections(Opts.CompressDebugSections);

-  MAI->setRelaxELFRelocations(Opts.RelaxELFRelocations);

  bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
  if (Opts.OutputPath.empty())
@@ -343,8 +349,6 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
    MOFI->setDarwinTargetVariantSDKVersion(Opts.DarwinTargetVariantSDKVersion);
  Ctx.setObjectFileInfo(MOFI.get());

-  if (Opts.SaveTemporaryLabels)
-    Ctx.setAllowTemporaryLabels(false);
  if (Opts.GenDwarfForAssembly)
    Ctx.setGenDwarfForAssembly(true);
  if (!Opts.DwarfDebugFlags.empty())
@@ -381,6 +385,9 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
  MCOptions.MCNoWarn = Opts.NoWarn;
  MCOptions.MCFatalWarnings = Opts.FatalWarnings;
  MCOptions.MCNoTypeCheck = Opts.NoTypeCheck;
+  MCOptions.ShowMCInst = Opts.ShowInst;
+  MCOptions.AsmVerbose = true;
+  MCOptions.MCUseDwarfDirectory = MCTargetOptions::EnableDwarfDirectory;
  MCOptions.ABIName = Opts.TargetABI;

  // FIXME: There is a bit of code duplication with addPassesToEmitFile.
@@ -395,10 +402,8 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
        TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));

    auto FOut = std::make_unique<formatted_raw_ostream>(*Out);
-    Str.reset(TheTarget->createAsmStreamer(
-        Ctx, std::move(FOut), /*asmverbose*/ true,
-        /*useDwarfDirectory*/ true, IP, std::move(CE), std::move(MAB),
-        Opts.ShowInst));
+    Str.reset(TheTarget->createAsmStreamer(Ctx, std::move(FOut), IP,
+                                           std::move(CE), std::move(MAB)));
  } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
    Str.reset(createNullStreamer(Ctx));
  } else {
@@ -421,9 +426,7 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,

    Triple T(Opts.Triple);
    Str.reset(TheTarget->createMCObjectStreamer(
-        T, Ctx, std::move(MAB), std::move(OW), std::move(CE), *STI,
-        Opts.RelaxAll, Opts.IncrementalLinkerCompatible,
-        /*DWARFMustBeAtTheEnd*/ true));
+        T, Ctx, std::move(MAB), std::move(OW), std::move(CE), *STI));
    Str.get()->initSections(Opts.NoExecStack, *STI);
  }

@@ -436,9 +439,6 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
    Str.get()->emitZeros(1);
  }

-  // Assembly to object compilation should leverage assembly info.
-  Str->setUseAssemblerInfoForParsing(true);
-
  bool Failed = false;

  std::unique_ptr<MCAsmParser> Parser(
@@ -38,10 +38,17 @@ struct AssemblerInvocation {
  /// @{

  std::vector<std::string> IncludePaths;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned NoInitialTextSection : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned SaveTemporaryLabels : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned GenDwarfForAssembly : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned RelaxELFRelocations : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned SSE2AVX : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned Dwarf64 : 1;
  unsigned DwarfVersion;
  std::string DwarfDebugFlags;
@@ -66,7 +73,9 @@ struct AssemblerInvocation {
    FT_Obj   ///< Object file output.
  };
  FileType OutputType;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned ShowHelp : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned ShowVersion : 1;

  /// @}
@@ -74,28 +83,41 @@ struct AssemblerInvocation {
  /// @{

  unsigned OutputAsmVariant;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned ShowEncoding : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned ShowInst : 1;

  /// @}
  /// @name Assembler Options
  /// @{

+  LLVM_PREFERRED_TYPE(bool)
  unsigned RelaxAll : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned NoExecStack : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned FatalWarnings : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned NoWarn : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned NoTypeCheck : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned IncrementalLinkerCompatible : 1;
+  LLVM_PREFERRED_TYPE(bool)
  unsigned EmbedBitcode : 1;

  /// Whether to emit DWARF unwind info.
  EmitDwarfUnwindType EmitDwarfUnwind;

  // Whether to emit compact-unwind for non-canonical entries.
-  // Note: maybe overridden by other constraints.
+  // Note: maybe overriden by other constraints.
+  LLVM_PREFERRED_TYPE(bool)
  unsigned EmitCompactUnwindNonCanonical : 1;

+  LLVM_PREFERRED_TYPE(bool)
+  unsigned Crel : 1;
+
  /// The name of the relocation model to use.
  std::string RelocationModel;

@@ -126,6 +148,7 @@ public:
    ShowInst = 0;
    ShowEncoding = 0;
    RelaxAll = 0;
+    SSE2AVX = 0;
    NoExecStack = 0;
    FatalWarnings = 0;
    NoWarn = 0;
@@ -136,6 +159,7 @@ public:
    EmbedBitcode = 0;
    EmitDwarfUnwind = EmitDwarfUnwindType::Default;
    EmitCompactUnwindNonCanonical = false;
+    Crel = false;
  }

  static bool CreateFromArgs(AssemblerInvocation &Res,
@@ -26,7 +26,7 @@ func NewConfig(options *compileopts.Options) (*compileopts.Config, error) {

 	// Version range supported by TinyGo.
 	const minorMin = 19
-	const minorMax = 23
+	const minorMax = 24

 	// Check that we support this Go toolchain version.
 	gorootMajor, gorootMinor, err := goenv.GetGorootVersion()
@@ -36,7 +36,7 @@ func NewConfig(options *compileopts.Options) (*compileopts.Config, error) {
 	if gorootMajor != 1 || gorootMinor < minorMin || gorootMinor > minorMax {
 		// Note: when this gets updated, also update the Go compatibility matrix:
 		// https://github.com/tinygo-org/tinygo-site/blob/dev/content/docs/reference/go-compat-matrix.md
-		return nil, fmt.Errorf("requires go version 1.19 through 1.23, got go%d.%d", gorootMajor, gorootMinor)
+		return nil, fmt.Errorf("requires go version 1.%d through 1.%d, got go%d.%d", minorMin, minorMax, gorootMajor, gorootMinor)
 	}

 	// Check that the Go toolchain version isn't too new, if we haven't been
@@ -128,6 +128,7 @@ var libMusl = Library{
 			"malloc/mallocng/*.c",
 			"mman/*.c",
 			"math/*.c",
+			"misc/*.c",
 			"multibyte/*.c",
 			"signal/" + arch + "/*.s",
 			"signal/*.c",
@@ -34,6 +34,7 @@ var libPicolibc = Library{
 			"-D__OBSOLETE_MATH_FLOAT=1", // use old math code that doesn't expect a FPU
 			"-D__OBSOLETE_MATH_DOUBLE=0",
 			"-D_WANT_IO_C99_FORMATS",
+			"-D__PICOLIBC_ERRNO_FUNCTION=__errno_location",
 			"-nostdlibinc",
 			"-isystem", newlibDir + "/libc/include",
 			"-I" + newlibDir + "/libc/tinystdio",
@@ -0,0 +1,56 @@
+package builder
+
+import (
+	_ "embed"
+	"fmt"
+	"html/template"
+	"os"
+)
+
+//go:embed size-report.html
+var sizeReportBase string
+
+func writeSizeReport(sizes *programSize, filename, pkgName string) error {
+	tmpl, err := template.New("report").Parse(sizeReportBase)
+	if err != nil {
+		return err
+	}
+
+	f, err := os.Create(filename)
+	if err != nil {
+		return fmt.Errorf("could not open report file: %w", err)
+	}
+	defer f.Close()
+
+	// Prepare data for the report.
+	type sizeLine struct {
+		Name string
+		Size *packageSize
+	}
+	programData := []sizeLine{}
+	for _, name := range sizes.sortedPackageNames() {
+		pkgSize := sizes.Packages[name]
+		programData = append(programData, sizeLine{
+			Name: name,
+			Size: pkgSize,
+		})
+	}
+	sizeTotal := map[string]uint64{
+		"code":   sizes.Code,
+		"rodata": sizes.ROData,
+		"data":   sizes.Data,
+		"bss":    sizes.BSS,
+		"flash":  sizes.Flash(),
+	}
+
+	// Write the report.
+	err = tmpl.Execute(f, map[string]any{
+		"pkgName":   pkgName,
+		"sizes":     programData,
+		"sizeTotal": sizeTotal,
+	})
+	if err != nil {
+		return fmt.Errorf("could not create report file: %w", err)
+	}
+	return nil
+}
@@ -0,0 +1,109 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <title>Size Report for {{.pkgName}}</title>
+    <meta charset="utf-8"/>
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-QWTKZyjpPEjISv5WaRU9OFeRpok6YctnYmDr5pNlyT2bRjXh0JMhjY6hW+ALEwIH" crossorigin="anonymous">
+    <style>
+
+.table-vertical-border {
+  border-left: calc(var(--bs-border-width) * 2) solid currentcolor;
+}
+
+/* Hover on only the rows that are clickable. */
+.row-package:hover > * {
+  --bs-table-color-state: var(--bs-table-hover-color);
+  --bs-table-bg-state: var(--bs-table-hover-bg);
+}
+
+    </style>
+  </head>
+  <body>
+    <div class="container-xxl">
+      <h1>Size Report for {{.pkgName}}</h1>
+
+      <p>How much space is used by Go packages, C libraries, and other bits to set up the program environment.</p>
+
+      <ul>
+        <li><strong>Code</strong> is the actual program code (machine code instructions).</li>
+        <li><strong>Read-only data</strong> are read-only global variables. On most microcontrollers, these are stored in flash and do not take up any RAM.</li>
+        <li><strong>Data</strong> are writable global variables with a non-zero initializer. On microcontrollers, they are copied from flash to RAM on reset.</li>
+        <li><strong>BSS</strong> are writable global variables that are zero initialized. They do not take up any space in the binary, but do take up RAM. On microcontrollers, this area is zeroed on reset.</li>
+      </ul>
+
+      <p>The binary size consists of code, read-only data, and data. On microcontrollers, this is exactly the size of the firmware image. On other systems, there is some extra overhead: binary metadata (headers of the ELF/MachO/COFF file), debug information, exception tables, symbol names, etc. Using <code>-no-debug</code> strips most of those.</p>
+
+      <h2>Program breakdown</h2>
+
+      <p>You can click on the rows below to see which files contribute to the binary size.</p>
+
+      <div class="table-responsive">
+        <table class="table w-auto">
+          <thead>
+            <tr>
+              <th>Package</th>
+              <th class="table-vertical-border">Code</th>
+              <th>Read-only data</th>
+              <th>Data</th>
+              <th title="zero-initialized data">BSS</th>
+              <th class="table-vertical-border" style="min-width: 16em">Binary size</th>
+            </tr>
+          </thead>
+          <tbody class="table-group-divider">
+            {{range $i, $pkg := .sizes}}
+            <tr class="row-package" data-collapse=".collapse-row-{{$i}}">
+              <td>{{.Name}}</td>
+              <td class="table-vertical-border">{{.Size.Code}}</td>
+              <td>{{.Size.ROData}}</td>
+              <td>{{.Size.Data}}</td>
+              <td>{{.Size.BSS}}</td>
+              <td class="table-vertical-border" style="background: linear-gradient(to right, var(--bs-info-bg-subtle) {{.Size.FlashPercent}}%, var(--bs-table-bg) {{.Size.FlashPercent}}%)">
+                {{.Size.Flash}}
+              </td>
+            </tr>
+            {{range $filename, $sizes := .Size.Sub}}
+            <tr class="table-secondary collapse collapse-row-{{$i}}">
+              <td class="ps-4">
+                {{if eq $filename ""}}
+                  (unknown file)
+                {{else}}
+                  {{$filename}}
+                {{end}}
+              </td>
+              <td class="table-vertical-border">{{$sizes.Code}}</td>
+              <td>{{$sizes.ROData}}</td>
+              <td>{{$sizes.Data}}</td>
+              <td>{{$sizes.BSS}}</td>
+              <td class="table-vertical-border" style="background: linear-gradient(to right, var(--bs-info-bg-subtle) {{$sizes.FlashPercent}}%, var(--bs-table-bg) {{$sizes.FlashPercent}}%)">
+                {{$sizes.Flash}}
+              </td>
+            </tr>
+            {{end}}
+            {{end}}
+          </tbody>
+          <tfoot class="table-group-divider">
+            <tr>
+              <th>Total</th>
+              <td class="table-vertical-border">{{.sizeTotal.code}}</td>
+              <td>{{.sizeTotal.rodata}}</td>
+              <td>{{.sizeTotal.data}}</td>
+              <td>{{.sizeTotal.bss}}</td>
+              <td class="table-vertical-border">{{.sizeTotal.flash}}</td>
+            </tr>
+          </tfoot>
+        </table>
+      </div>
+    </div>
+    <script>
+// Make table rows toggleable to show filenames.
+for (let clickable of document.querySelectorAll('.row-package')) {
+  clickable.addEventListener('click', e => {
+    for (let row of document.querySelectorAll(clickable.dataset.collapse)) {
+      row.classList.toggle('show');
+    }
+  });
+}
+    </script>
+  </body>
+</html>
@@ -12,6 +12,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"runtime"
 	"sort"
 	"strings"

@@ -24,7 +25,7 @@ const sizesDebug = false

 // programSize contains size statistics per package of a compiled program.
 type programSize struct {
-	Packages map[string]packageSize
+	Packages map[string]*packageSize
 	Code     uint64
 	ROData   uint64
 	Data     uint64
@@ -52,13 +53,29 @@ func (ps *programSize) RAM() uint64 {
 	return ps.Data + ps.BSS
 }

+// Return the package size information for a given package path, creating it if
+// it doesn't exist yet.
+func (ps *programSize) getPackage(path string) *packageSize {
+	if field, ok := ps.Packages[path]; ok {
+		return field
+	}
+	field := &packageSize{
+		Program: ps,
+		Sub:     map[string]*packageSize{},
+	}
+	ps.Packages[path] = field
+	return field
+}
+
 // packageSize contains the size of a package, calculated from the linked object
 // file.
 type packageSize struct {
-	Code   uint64
-	ROData uint64
-	Data   uint64
-	BSS    uint64
+	Program *programSize
+	Code    uint64
+	ROData  uint64
+	Data    uint64
+	BSS     uint64
+	Sub     map[string]*packageSize
 }

 // Flash usage in regular microcontrollers.
@@ -71,6 +88,31 @@ func (ps *packageSize) RAM() uint64 {
 	return ps.Data + ps.BSS
 }

+// Flash usage in regular microcontrollers, as a percentage of the total flash
+// usage of the program.
+func (ps *packageSize) FlashPercent() float64 {
+	return float64(ps.Flash()) / float64(ps.Program.Flash()) * 100
+}
+
+// Add a single size data point to this package.
+// This must only be called while calculating package size, not afterwards.
+func (ps *packageSize) addSize(getField func(*packageSize, bool) *uint64, filename string, size uint64, isVariable bool) {
+	if size == 0 {
+		return
+	}
+
+	// Add size for the package.
+	*getField(ps, isVariable) += size
+
+	// Add size for file inside package.
+	sub, ok := ps.Sub[filename]
+	if !ok {
+		sub = &packageSize{Program: ps.Program}
+		ps.Sub[filename] = sub
+	}
+	*getField(sub, isVariable) += size
+}
+
 // A mapping of a single chunk of code or data to a file path.
 type addressLine struct {
 	Address    uint64
@@ -194,11 +236,22 @@ func readProgramSizeFromDWARF(data *dwarf.Data, codeOffset, codeAlignment uint64
 				if !prevLineEntry.EndSequence {
 					// The chunk describes the code from prevLineEntry to
 					// lineEntry.
+					path := prevLineEntry.File.Name
+					if runtime.GOOS == "windows" {
+						// Work around a Clang bug on Windows:
+						// https://github.com/llvm/llvm-project/issues/117317
+						path = strings.ReplaceAll(path, "\\\\", "\\")
+
+						// wasi-libc likes to use forward slashes, but we
+						// canonicalize everything to use backwards slashes as
+						// is common on Windows.
+						path = strings.ReplaceAll(path, "/", "\\")
+					}
 					line := addressLine{
 						Address: prevLineEntry.Address + codeOffset,
 						Length:  lineEntry.Address - prevLineEntry.Address,
 						Align:   codeAlignment,
-						File:    prevLineEntry.File.Name,
+						File:    path,
 					}
 					if line.Length != 0 {
 						addresses = append(addresses, line)
@@ -773,49 +826,40 @@ func loadProgramSize(path string, packagePathMap map[string]string) (*programSiz

 	// Now finally determine the binary/RAM size usage per package by going
 	// through each allocated section.
-	sizes := make(map[string]packageSize)
+	sizes := make(map[string]*packageSize)
+	program := &programSize{
+		Packages: sizes,
+	}
 	for _, section := range sections {
 		switch section.Type {
 		case memoryCode:
-			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
-				field := sizes[path]
+			readSection(section, addresses, program, func(ps *packageSize, isVariable bool) *uint64 {
 				if isVariable {
-					field.ROData += size
-				} else {
-					field.Code += size
+					return &ps.ROData
 				}
-				sizes[path] = field
+				return &ps.Code
 			}, packagePathMap)
 		case memoryROData:
-			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
-				field := sizes[path]
-				field.ROData += size
-				sizes[path] = field
+			readSection(section, addresses, program, func(ps *packageSize, isVariable bool) *uint64 {
+				return &ps.ROData
 			}, packagePathMap)
 		case memoryData:
-			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
-				field := sizes[path]
-				field.Data += size
-				sizes[path] = field
+			readSection(section, addresses, program, func(ps *packageSize, isVariable bool) *uint64 {
+				return &ps.Data
 			}, packagePathMap)
 		case memoryBSS:
-			readSection(section, addresses, func(path string, size uint64, isVariable bool) {
-				field := sizes[path]
-				field.BSS += size
-				sizes[path] = field
+			readSection(section, addresses, program, func(ps *packageSize, isVariable bool) *uint64 {
+				return &ps.BSS
 			}, packagePathMap)
 		case memoryStack:
 			// We store the C stack as a pseudo-package.
-			sizes["C stack"] = packageSize{
-				BSS: section.Size,
-			}
+			program.getPackage("C stack").addSize(func(ps *packageSize, isVariable bool) *uint64 {
+				return &ps.BSS
+			}, "", section.Size, false)
 		}
 	}

 	// ...and summarize the results.
-	program := &programSize{
-		Packages: sizes,
-	}
 	for _, pkg := range sizes {
 		program.Code += pkg.Code
 		program.ROData += pkg.ROData
@@ -826,8 +870,8 @@ func loadProgramSize(path string, packagePathMap map[string]string) (*programSiz
 }

 // 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) {
+// belongs.
+func readSection(section memorySection, addresses []addressLine, program *programSize, getField func(*packageSize, bool) *uint64, 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
@@ -849,9 +893,9 @@ func readSection(section memorySection, addresses []addressLine, addSize func(st
 			addrAligned := (addr + line.Align - 1) &^ (line.Align - 1)
 			if line.Align > 1 && addrAligned >= line.Address {
 				// It is, assume that's what causes the gap.
-				addSize("(padding)", line.Address-addr, true)
+				program.getPackage("(padding)").addSize(getField, "", line.Address-addr, true)
 			} else {
-				addSize("(unknown)", line.Address-addr, false)
+				program.getPackage("(unknown)").addSize(getField, "", line.Address-addr, false)
 				if sizesDebug {
 					fmt.Printf("%08x..%08x %5d:  unknown (gap), alignment=%d\n", addr, line.Address, line.Address-addr, line.Align)
 				}
@@ -873,7 +917,8 @@ func readSection(section memorySection, addresses []addressLine, addSize func(st
 			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)
+		packagePath, filename := findPackagePath(line.File, packagePathMap)
+		program.getPackage(packagePath).addSize(getField, filename, length, line.IsVariable)
 		addr = line.Address + line.Length
 	}
 	if addr < sectionEnd {
@@ -882,9 +927,9 @@ func readSection(section memorySection, addresses []addressLine, addSize func(st
 		if section.Align > 1 && addrAligned >= sectionEnd {
 			// The gap is caused by the section alignment.
 			// For example, if a .rodata section ends with a non-aligned string.
-			addSize("(padding)", sectionEnd-addr, true)
+			program.getPackage("(padding)").addSize(getField, "", sectionEnd-addr, true)
 		} else {
-			addSize("(unknown)", sectionEnd-addr, false)
+			program.getPackage("(unknown)").addSize(getField, "", sectionEnd-addr, false)
 			if sizesDebug {
 				fmt.Printf("%08x..%08x %5d:  unknown (end), alignment=%d\n", addr, sectionEnd, sectionEnd-addr, section.Align)
 			}
@@ -894,17 +939,25 @@ func readSection(section memorySection, addresses []addressLine, addSize func(st

 // 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 {
+func findPackagePath(path string, packagePathMap map[string]string) (packagePath, filename string) {
 	// Check whether this path is part of one of the compiled packages.
 	packagePath, ok := packagePathMap[filepath.Dir(path)]
-	if !ok {
+	if ok {
+		// Directory is known as a Go package.
+		// Add the file itself as well.
+		filename = filepath.Base(path)
+	} else {
 		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 strings.HasPrefix(path, filepath.Join(goenv.Get("TINYGOROOT"), "llvm-project")) {
+			// package, with a "C" prefix. For example: "C picolibc" for the
+			// baremetal libc.
+			libPath := strings.TrimPrefix(path, filepath.Join(goenv.Get("TINYGOROOT"), "lib")+string(os.PathSeparator))
+			parts := strings.SplitN(libPath, string(os.PathSeparator), 2)
+			packagePath = "C " + parts[0]
+			filename = parts[1]
+		} else if prefix := filepath.Join(goenv.Get("TINYGOROOT"), "llvm-project", "compiler-rt"); strings.HasPrefix(path, prefix) {
 			packagePath = "C compiler-rt"
+			filename = strings.TrimPrefix(path, prefix+string(os.PathSeparator))
 		} else if packageSymbolRegexp.MatchString(path) {
 			// Parse symbol names like main$alloc or runtime$string.
 			packagePath = path[:strings.LastIndex(path, "$")]
@@ -927,9 +980,11 @@ func findPackagePath(path string, packagePathMap map[string]string) string {
 			// 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
+			// This is some other path. Not sure what it is, so just emit its
+			// directory as a fallback.
+			packagePath = filepath.Dir(path)
+			filename = filepath.Base(path)
 		}
 	}
-	return packagePath
+	return
 }
@@ -1,6 +1,7 @@
 package builder

 import (
+	"regexp"
 	"runtime"
 	"testing"
 	"time"
@@ -41,9 +42,9 @@ func TestBinarySize(t *testing.T) {
 	// This is a small number of very diverse targets that we want to test.
 	tests := []sizeTest{
 		// microcontrollers
-		{"hifive1b", "examples/echo", 4600, 280, 0, 2268},
-		{"microbit", "examples/serial", 2908, 388, 8, 2272},
-		{"wioterminal", "examples/pininterrupt", 6140, 1484, 116, 6832},
+		{"hifive1b", "examples/echo", 4560, 280, 0, 2268},
+		{"microbit", "examples/serial", 2916, 388, 8, 2272},
+		{"wioterminal", "examples/pininterrupt", 7359, 1489, 116, 6912},

 		// TODO: also check wasm. Right now this is difficult, because
 		// wasm binaries are run through wasm-opt and therefore the
@@ -55,26 +56,7 @@ func TestBinarySize(t *testing.T) {
 			t.Parallel()

 			// Build the binary.
-			options := compileopts.Options{
-				Target:        tc.target,
-				Opt:           "z",
-				Semaphore:     sema,
-				InterpTimeout: 60 * time.Second,
-				Debug:         true,
-				VerifyIR:      true,
-			}
-			target, err := compileopts.LoadTarget(&options)
-			if err != nil {
-				t.Fatal("could not load target:", err)
-			}
-			config := &compileopts.Config{
-				Options: &options,
-				Target:  target,
-			}
-			result, err := Build(tc.path, "", t.TempDir(), config)
-			if err != nil {
-				t.Fatal("could not build:", err)
-			}
+			result := buildBinary(t, tc.target, tc.path)

 			// Check whether the size of the binary matches the expected size.
 			sizes, err := loadProgramSize(result.Executable, nil)
@@ -90,3 +72,69 @@ func TestBinarySize(t *testing.T) {
 		})
 	}
 }
+
+// Check that the -size=full flag attributes binary size to the correct package
+// without filesystem paths and things like that.
+func TestSizeFull(t *testing.T) {
+	tests := []string{
+		"microbit",
+		"wasip1",
+	}
+
+	libMatch := regexp.MustCompile(`^C [a-z -]+$`) // example: "C interrupt vector"
+	pkgMatch := regexp.MustCompile(`^[a-z/]+$`)    // example: "internal/task"
+
+	for _, target := range tests {
+		target := target
+		t.Run(target, func(t *testing.T) {
+			t.Parallel()
+
+			// Build the binary.
+			result := buildBinary(t, target, "examples/serial")
+
+			// Check whether the binary doesn't contain any unexpected package
+			// names.
+			sizes, err := loadProgramSize(result.Executable, result.PackagePathMap)
+			if err != nil {
+				t.Fatal("could not read program size:", err)
+			}
+			for _, pkg := range sizes.sortedPackageNames() {
+				if pkg == "(padding)" || pkg == "(unknown)" {
+					// TODO: correctly attribute all unknown binary size.
+					continue
+				}
+				if libMatch.MatchString(pkg) {
+					continue
+				}
+				if pkgMatch.MatchString(pkg) {
+					continue
+				}
+				t.Error("unexpected package name in size output:", pkg)
+			}
+		})
+	}
+}
+
+func buildBinary(t *testing.T, targetString, pkgName string) BuildResult {
+	options := compileopts.Options{
+		Target:        targetString,
+		Opt:           "z",
+		Semaphore:     sema,
+		InterpTimeout: 60 * time.Second,
+		Debug:         true,
+		VerifyIR:      true,
+	}
+	target, err := compileopts.LoadTarget(&options)
+	if err != nil {
+		t.Fatal("could not load target:", err)
+	}
+	config := &compileopts.Config{
+		Options: &options,
+		Target:  target,
+	}
+	result, err := Build(pkgName, "", t.TempDir(), config)
+	if err != nil {
+		t.Fatal("could not build:", err)
+	}
+	return result
+}
@@ -114,8 +114,8 @@ func parseLLDErrors(text string) error {

 		// Check for undefined symbols.
 		// This can happen in some cases like with CGo and //go:linkname tricker.
-		if matches := regexp.MustCompile(`^ld.lld: error: undefined symbol: (.*)\n`).FindStringSubmatch(message); matches != nil {
-			symbolName := matches[1]
+		if matches := regexp.MustCompile(`^ld.lld(-[0-9]+)?: error: undefined symbol: (.*)\n`).FindStringSubmatch(message); matches != nil {
+			symbolName := matches[2]
 			for _, line := range strings.Split(message, "\n") {
 				matches := regexp.MustCompile(`referenced by .* \(((.*):([0-9]+))\)`).FindStringSubmatch(line)
 				if matches != nil {
@@ -134,9 +134,9 @@ func parseLLDErrors(text string) error {
 		}

 		// Check for flash/RAM overflow.
-		if matches := regexp.MustCompile(`^ld.lld: error: section '(.*?)' will not fit in region '(.*?)': overflowed by ([0-9]+) bytes$`).FindStringSubmatch(message); matches != nil {
-			region := matches[2]
-			n, err := strconv.ParseUint(matches[3], 10, 64)
+		if matches := regexp.MustCompile(`^ld.lld(-[0-9]+)?: error: section '(.*?)' will not fit in region '(.*?)': overflowed by ([0-9]+) bytes$`).FindStringSubmatch(message); matches != nil {
+			region := matches[3]
+			n, err := strconv.ParseUint(matches[4], 10, 64)
 			if err != nil {
 				// Should not happen at all (unless it overflows an uint64 for some reason).
 				continue
@@ -18,6 +18,7 @@ import (
 	"go/scanner"
 	"go/token"
 	"path/filepath"
+	"sort"
 	"strconv"
 	"strings"

@@ -42,6 +43,7 @@ type cgoPackage struct {
 	fset            *token.FileSet
 	tokenFiles      map[string]*token.File
 	definedGlobally map[string]ast.Node
+	noescapingFuncs map[string]*noescapingFunc // #cgo noescape lines
 	anonDecls       map[interface{}]string
 	cflags          []string // CFlags from #cgo lines
 	ldflags         []string // LDFlags from #cgo lines
@@ -80,21 +82,28 @@ type bitfieldInfo struct {
 	endBit   int64 // may be 0 meaning "until the end of the field"
 }

+// Information about a #cgo noescape line in the source code.
+type noescapingFunc struct {
+	name string
+	pos  token.Pos
+	used bool // true if used somewhere in the source (for proper error reporting)
+}
+
 // cgoAliases list type aliases between Go and C, for types that are equivalent
 // in both languages. See addTypeAliases.
 var cgoAliases = map[string]string{
-	"C.int8_t":    "int8",
-	"C.int16_t":   "int16",
-	"C.int32_t":   "int32",
-	"C.int64_t":   "int64",
-	"C.uint8_t":   "uint8",
-	"C.uint16_t":  "uint16",
-	"C.uint32_t":  "uint32",
-	"C.uint64_t":  "uint64",
-	"C.uintptr_t": "uintptr",
-	"C.float":     "float32",
-	"C.double":    "float64",
-	"C._Bool":     "bool",
+	"_Cgo_int8_t":    "int8",
+	"_Cgo_int16_t":   "int16",
+	"_Cgo_int32_t":   "int32",
+	"_Cgo_int64_t":   "int64",
+	"_Cgo_uint8_t":   "uint8",
+	"_Cgo_uint16_t":  "uint16",
+	"_Cgo_uint32_t":  "uint32",
+	"_Cgo_uint64_t":  "uint64",
+	"_Cgo_uintptr_t": "uintptr",
+	"_Cgo_float":     "float32",
+	"_Cgo_double":    "float64",
+	"_Cgo__Bool":     "bool",
 }

 // builtinAliases are handled specially because they only exist on the Go side
@@ -136,38 +145,105 @@ typedef unsigned long long  _Cgo_ulonglong;
 // The string/bytes functions below implement C.CString etc. To make sure the
 // runtime doesn't need to know the C int type, lengths are converted to uintptr
 // first.
-// These functions will be modified to get a "C." prefix, so the source below
-// doesn't reflect the final AST.
-const generatedGoFilePrefix = `
+const generatedGoFilePrefixBase = `
+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func __GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func __GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func __CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+`
+
+const generatedGoFilePrefixOther = generatedGoFilePrefixBase + `
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
+}
+`
+
+// Windows uses fake errno values in the syscall package.
+// See for example: https://github.com/golang/go/issues/23468
+// TinyGo uses mingw-w64 though, which does have defined errno values. Since the
+// syscall package is the standard library one we can't change it, but we can
+// map the errno values to match the values in the syscall package.
+// Source of the errno values: lib/mingw-w64/mingw-w64-headers/crt/errno.h
+const generatedGoFilePrefixWindows = generatedGoFilePrefixBase + `
+var _Cgo___errno_mapping = [...]syscall.Errno{
+	1:  syscall.EPERM,
+	2:  syscall.ENOENT,
+	3:  syscall.ESRCH,
+	4:  syscall.EINTR,
+	5:  syscall.EIO,
+	6:  syscall.ENXIO,
+	7:  syscall.E2BIG,
+	8:  syscall.ENOEXEC,
+	9:  syscall.EBADF,
+	10: syscall.ECHILD,
+	11: syscall.EAGAIN,
+	12: syscall.ENOMEM,
+	13: syscall.EACCES,
+	14: syscall.EFAULT,
+	16: syscall.EBUSY,
+	17: syscall.EEXIST,
+	18: syscall.EXDEV,
+	19: syscall.ENODEV,
+	20: syscall.ENOTDIR,
+	21: syscall.EISDIR,
+	22: syscall.EINVAL,
+	23: syscall.ENFILE,
+	24: syscall.EMFILE,
+	25: syscall.ENOTTY,
+	27: syscall.EFBIG,
+	28: syscall.ENOSPC,
+	29: syscall.ESPIPE,
+	30: syscall.EROFS,
+	31: syscall.EMLINK,
+	32: syscall.EPIPE,
+	33: syscall.EDOM,
+	34: syscall.ERANGE,
+	36: syscall.EDEADLK,
+	38: syscall.ENAMETOOLONG,
+	39: syscall.ENOLCK,
+	40: syscall.ENOSYS,
+	41: syscall.ENOTEMPTY,
+	42: syscall.EILSEQ,
+}
+
+func _Cgo___get_errno() error {
+	num := _Cgo___get_errno_num()
+	if num < uintptr(len(_Cgo___errno_mapping)) {
+		if mapped := _Cgo___errno_mapping[num]; mapped != 0 {
+			return mapped
+		}
+	}
+	return syscall.Errno(num)
 }
 `

@@ -178,7 +254,7 @@ func CBytes(b []byte) unsafe.Pointer {
 // functions), the CFLAGS and LDFLAGS found in #cgo lines, and a map of file
 // hashes of the accessed C header files. If there is one or more error, it
 // returns these in the []error slice but still modifies the AST.
-func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cflags []string) ([]*ast.File, []string, []string, []string, map[string][]byte, []error) {
+func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cflags []string, goos string) ([]*ast.File, []string, []string, []string, map[string][]byte, []error) {
 	p := &cgoPackage{
 		packageName:     files[0].Name.Name,
 		currentDir:      dir,
@@ -186,6 +262,7 @@ func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cfl
 		fset:            fset,
 		tokenFiles:      map[string]*token.File{},
 		definedGlobally: map[string]ast.Node{},
+		noescapingFuncs: map[string]*noescapingFunc{},
 		anonDecls:       map[interface{}]string{},
 		visitedFiles:    map[string][]byte{},
 	}
@@ -210,7 +287,12 @@ func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cfl
 	// Construct a new in-memory AST for CGo declarations of this package.
 	// The first part is written as Go code that is then parsed, but more code
 	// is added later to the AST to declare functions, globals, etc.
-	goCode := "package " + files[0].Name.Name + "\n\n" + generatedGoFilePrefix
+	goCode := "package " + files[0].Name.Name + "\n\n"
+	if goos == "windows" {
+		goCode += generatedGoFilePrefixWindows
+	} else {
+		goCode += generatedGoFilePrefixOther
+	}
 	p.generated, err = parser.ParseFile(fset, dir+"/!cgo.go", goCode, parser.ParseComments)
 	if err != nil {
 		// This is always a bug in the cgo package.
@@ -220,23 +302,6 @@ func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cfl
 	// If the Comments field is not set to nil, the go/format package will get
 	// confused about where comments should go.
 	p.generated.Comments = nil
-	// Adjust some of the functions in there.
-	for _, decl := range p.generated.Decls {
-		switch decl := decl.(type) {
-		case *ast.FuncDecl:
-			switch decl.Name.Name {
-			case "CString", "GoString", "GoStringN", "__GoStringN", "GoBytes", "__GoBytes", "CBytes", "__CBytes":
-				// Adjust the name to have a "C." prefix so it is correctly
-				// resolved.
-				decl.Name.Name = "C." + decl.Name.Name
-			}
-		}
-	}
-	// Patch some types, for example *C.char in C.CString.
-	cf := p.newCGoFile(nil, -1) // dummy *cgoFile for the walker
-	astutil.Apply(p.generated, func(cursor *astutil.Cursor) bool {
-		return cf.walker(cursor, nil)
-	}, nil)

 	// Find `import "C"` C fragments in the file.
 	p.cgoHeaders = make([]string, len(files)) // combined CGo header fragment for each file
@@ -315,7 +380,7 @@ func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cfl
 			Tok:    token.TYPE,
 		}
 		for _, name := range builtinAliases {
-			typeSpec := p.getIntegerType("C."+name, names["_Cgo_"+name])
+			typeSpec := p.getIntegerType("_Cgo_"+name, names["_Cgo_"+name])
 			gen.Specs = append(gen.Specs, typeSpec)
 		}
 		p.generated.Decls = append(p.generated.Decls, gen)
@@ -344,6 +409,22 @@ func Process(files []*ast.File, dir, importPath string, fset *token.FileSet, cfl
 		})
 	}

+	// Show an error when a #cgo noescape line isn't used in practice.
+	// This matches upstream Go. I think the goal is to avoid issues with
+	// misspelled function names, which seems very useful.
+	var unusedNoescapeLines []*noescapingFunc
+	for _, value := range p.noescapingFuncs {
+		if !value.used {
+			unusedNoescapeLines = append(unusedNoescapeLines, value)
+		}
+	}
+	sort.SliceStable(unusedNoescapeLines, func(i, j int) bool {
+		return unusedNoescapeLines[i].pos < unusedNoescapeLines[j].pos
+	})
+	for _, value := range unusedNoescapeLines {
+		p.addError(value.pos, fmt.Sprintf("function %#v in #cgo noescape line is not used", value.name))
+	}
+
 	// Print the newly generated in-memory AST, for debugging.
 	//ast.Print(fset, p.generated)

@@ -409,6 +490,33 @@ func (p *cgoPackage) parseCGoPreprocessorLines(text string, pos token.Pos) strin
 		}
 		text = text[:lineStart] + string(spaces) + text[lineEnd:]

+		allFields := strings.Fields(line[4:])
+		switch allFields[0] {
+		case "noescape":
+			// The code indicates that pointer parameters will not be captured
+			// by the called C function.
+			if len(allFields) < 2 {
+				p.addErrorAfter(pos, text[:lineStart], "missing function name in #cgo noescape line")
+				continue
+			}
+			if len(allFields) > 2 {
+				p.addErrorAfter(pos, text[:lineStart], "multiple function names in #cgo noescape line")
+				continue
+			}
+			name := allFields[1]
+			p.noescapingFuncs[name] = &noescapingFunc{
+				name: name,
+				pos:  pos,
+				used: false,
+			}
+			continue
+		case "nocallback":
+			// We don't do anything special when calling a C function, so there
+			// appears to be no optimization that we can do here.
+			// Accept, but ignore the parameter for compatibility.
+			continue
+		}
+
 		// Get the text before the colon in the #cgo directive.
 		colon := strings.IndexByte(line, ':')
 		if colon < 0 {
@@ -1145,7 +1253,7 @@ func (p *cgoPackage) getUnnamedDeclName(prefix string, itf interface{}) string {
 func (f *cgoFile) getASTDeclName(name string, found clangCursor, iscall bool) string {
 	// Some types are defined in stdint.h and map directly to a particular Go
 	// type.
-	if alias := cgoAliases["C."+name]; alias != "" {
+	if alias := cgoAliases["_Cgo_"+name]; alias != "" {
 		return alias
 	}
 	node := f.getASTDeclNode(name, found)
@@ -1155,7 +1263,7 @@ func (f *cgoFile) getASTDeclName(name string, found clangCursor, iscall bool) st
 		}
 		return node.Name.Name
 	}
-	return "C." + name
+	return "_Cgo_" + name
 }

 // getASTDeclNode will declare the given C AST node (if not already defined) and
@@ -1255,8 +1363,8 @@ extern __typeof(%s) %s __attribute__((alias(%#v)));
 	case *elaboratedTypeInfo:
 		// Add struct bitfields.
 		for _, bitfield := range elaboratedType.bitfields {
-			f.createBitfieldGetter(bitfield, "C."+name)
-			f.createBitfieldSetter(bitfield, "C."+name)
+			f.createBitfieldGetter(bitfield, "_Cgo_"+name)
+			f.createBitfieldSetter(bitfield, "_Cgo_"+name)
 		}
 		if elaboratedType.unionSize != 0 {
 			// Create union getters/setters.
@@ -1265,7 +1373,7 @@ extern __typeof(%s) %s __attribute__((alias(%#v)));
 					f.addError(elaboratedType.pos, fmt.Sprintf("union must have field with a single name, it has %d names", len(field.Names)))
 					continue
 				}
-				f.createUnionAccessor(field, "C."+name)
+				f.createUnionAccessor(field, "_Cgo_"+name)
 			}
 		}
 	}
@@ -1279,6 +1387,45 @@ extern __typeof(%s) %s __attribute__((alias(%#v)));
 // separate namespace (no _Cgo_ hacks like in gc).
 func (f *cgoFile) walker(cursor *astutil.Cursor, names map[string]clangCursor) bool {
 	switch node := cursor.Node().(type) {
+	case *ast.AssignStmt:
+		// An assign statement could be something like this:
+		//
+		//   val, errno := C.some_func()
+		//
+		// Check whether it looks like that, and if so, read the errno value and
+		// return it as the second return value. The call will be transformed
+		// into something like this:
+		//
+		//   val, errno := C.some_func(), C.__get_errno()
+		if len(node.Lhs) != 2 || len(node.Rhs) != 1 {
+			return true
+		}
+		rhs, ok := node.Rhs[0].(*ast.CallExpr)
+		if !ok {
+			return true
+		}
+		fun, ok := rhs.Fun.(*ast.SelectorExpr)
+		if !ok {
+			return true
+		}
+		x, ok := fun.X.(*ast.Ident)
+		if !ok {
+			return true
+		}
+		if found, ok := names[fun.Sel.Name]; ok && x.Name == "C" {
+			// Replace "C"."some_func" into "C.somefunc".
+			rhs.Fun = &ast.Ident{
+				NamePos: x.NamePos,
+				Name:    f.getASTDeclName(fun.Sel.Name, found, true),
+			}
+			// Add the errno value as the second value in the statement.
+			node.Rhs = append(node.Rhs, &ast.CallExpr{
+				Fun: &ast.Ident{
+					NamePos: node.Lhs[1].End(),
+					Name:    "_Cgo___get_errno",
+				},
+			})
+		}
 	case *ast.CallExpr:
 		fun, ok := node.Fun.(*ast.SelectorExpr)
 		if !ok {
@@ -1300,7 +1447,7 @@ func (f *cgoFile) walker(cursor *astutil.Cursor, names map[string]clangCursor) b
 			return true
 		}
 		if x.Name == "C" {
-			name := "C." + node.Sel.Name
+			name := "_Cgo_" + node.Sel.Name
 			if found, ok := names[node.Sel.Name]; ok {
 				name = f.getASTDeclName(node.Sel.Name, found, false)
 			}
@@ -56,7 +56,7 @@ func TestCGo(t *testing.T) {
 			}

 			// Process the AST with CGo.
-			cgoFiles, _, _, _, _, cgoErrors := Process([]*ast.File{f}, "testdata", "main", fset, cflags)
+			cgoFiles, _, _, _, _, cgoErrors := Process([]*ast.File{f}, "testdata", "main", fset, cflags, "linux")

 			// Check the AST for type errors.
 			var typecheckErrors []error
@@ -64,7 +64,7 @@ func TestCGo(t *testing.T) {
 				Error: func(err error) {
 					typecheckErrors = append(typecheckErrors, err)
 				},
-				Importer: simpleImporter{},
+				Importer: newSimpleImporter(),
 				Sizes:    types.SizesFor("gccgo", "arm"),
 			}
 			_, err = config.Check("", fset, append([]*ast.File{f}, cgoFiles...), nil)
@@ -202,14 +202,33 @@ func Test_cgoPackage_isEquivalentAST(t *testing.T) {
 }

 // simpleImporter implements the types.Importer interface, but only allows
-// importing the unsafe package.
+// importing the syscall and unsafe packages.
 type simpleImporter struct {
+	syscallPkg *types.Package
+}
+
+func newSimpleImporter() *simpleImporter {
+	i := &simpleImporter{}
+
+	// Implement a dummy syscall package with the Errno type.
+	i.syscallPkg = types.NewPackage("syscall", "syscall")
+	obj := types.NewTypeName(token.NoPos, i.syscallPkg, "Errno", nil)
+	named := types.NewNamed(obj, nil, nil)
+	i.syscallPkg.Scope().Insert(obj)
+	named.SetUnderlying(types.Typ[types.Uintptr])
+	sig := types.NewSignatureType(nil, nil, nil, types.NewTuple(), types.NewTuple(types.NewParam(token.NoPos, i.syscallPkg, "", types.Typ[types.String])), false)
+	named.AddMethod(types.NewFunc(token.NoPos, i.syscallPkg, "Error", sig))
+	i.syscallPkg.MarkComplete()
+
+	return i
 }

 // Import implements the Importer interface. For testing usage only: it only
 // supports importing the unsafe package.
-func (i simpleImporter) Import(path string) (*types.Package, error) {
+func (i *simpleImporter) Import(path string) (*types.Package, error) {
 	switch path {
+	case "syscall":
+		return i.syscallPkg, nil
 	case "unsafe":
 		return types.Unsafe, nil
 	default:
@@ -65,9 +65,22 @@ unsigned tinygo_clang_Cursor_isAnonymous(GoCXCursor c);
 unsigned tinygo_clang_Cursor_isBitField(GoCXCursor c);
 unsigned tinygo_clang_Cursor_isMacroFunctionLike(GoCXCursor c);

+// Fix some warnings on Windows ARM. Without the __declspec(dllexport), it gives warnings like this:
+//     In file included from _cgo_export.c:4:
+//     cgo-gcc-export-header-prolog:49:34: warning: redeclaration of 'tinygo_clang_globals_visitor' should not add 'dllexport' attribute [-Wdll-attribute-on-redeclaration]
+//     libclang.go:68:5: note: previous declaration is here
+// See: https://github.com/golang/go/issues/49721
+#if defined(_WIN32)
+#define CGO_DECL // __declspec(dllexport)
+#else
+#define CGO_DECL
+#endif
+
+CGO_DECL
 int tinygo_clang_globals_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
+CGO_DECL
 int tinygo_clang_struct_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
-int tinygo_clang_enum_visitor(GoCXCursor c, GoCXCursor parent, CXClientData client_data);
+CGO_DECL
 void tinygo_clang_inclusion_visitor(CXFile included_file, CXSourceLocation *inclusion_stack, unsigned include_len, CXClientData client_data);
 */
 import "C"
@@ -206,7 +219,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		numArgs := int(C.tinygo_clang_Cursor_getNumArguments(c))
 		obj := &ast.Object{
 			Kind: ast.Fun,
-			Name: "C." + name,
+			Name: "_Cgo_" + name,
 		}
 		exportName := name
 		localName := name
@@ -244,7 +257,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 			},
 			Name: &ast.Ident{
 				NamePos: pos,
-				Name:    "C." + localName,
+				Name:    "_Cgo_" + localName,
 				Obj:     obj,
 			},
 			Type: &ast.FuncType{
@@ -256,10 +269,18 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 				},
 			},
 		}
+		var doc []string
 		if C.clang_isFunctionTypeVariadic(cursorType) != 0 {
+			doc = append(doc, "//go:variadic")
+		}
+		if _, ok := f.noescapingFuncs[name]; ok {
+			doc = append(doc, "//go:noescape")
+			f.noescapingFuncs[name].used = true
+		}
+		if len(doc) != 0 {
 			decl.Doc.List = append(decl.Doc.List, &ast.Comment{
 				Slash: pos - 1,
-				Text:  "//go:variadic",
+				Text:  strings.Join(doc, "\n"),
 			})
 		}
 		for i := 0; i < numArgs; i++ {
@@ -298,7 +319,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		return decl, stringSignature
 	case C.CXCursor_StructDecl, C.CXCursor_UnionDecl:
 		typ := f.makeASTRecordType(c, pos)
-		typeName := "C." + name
+		typeName := "_Cgo_" + name
 		typeExpr := typ.typeExpr
 		if typ.unionSize != 0 {
 			// Convert to a single-field struct type.
@@ -319,7 +340,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		obj.Decl = typeSpec
 		return typeSpec, typ
 	case C.CXCursor_TypedefDecl:
-		typeName := "C." + name
+		typeName := "_Cgo_" + name
 		underlyingType := C.tinygo_clang_getTypedefDeclUnderlyingType(c)
 		obj := &ast.Object{
 			Kind: ast.Typ,
@@ -357,12 +378,12 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		}
 		obj := &ast.Object{
 			Kind: ast.Var,
-			Name: "C." + name,
+			Name: "_Cgo_" + name,
 		}
 		valueSpec := &ast.ValueSpec{
 			Names: []*ast.Ident{{
 				NamePos: pos,
-				Name:    "C." + name,
+				Name:    "_Cgo_" + name,
 				Obj:     obj,
 			}},
 			Type: typeExpr,
@@ -386,12 +407,12 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		}
 		obj := &ast.Object{
 			Kind: ast.Con,
-			Name: "C." + name,
+			Name: "_Cgo_" + name,
 		}
 		valueSpec := &ast.ValueSpec{
 			Names: []*ast.Ident{{
 				NamePos: pos,
-				Name:    "C." + name,
+				Name:    "_Cgo_" + name,
 				Obj:     obj,
 			}},
 			Values: []ast.Expr{expr},
@@ -402,7 +423,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 	case C.CXCursor_EnumDecl:
 		obj := &ast.Object{
 			Kind: ast.Typ,
-			Name: "C." + name,
+			Name: "_Cgo_" + name,
 		}
 		underlying := C.tinygo_clang_getEnumDeclIntegerType(c)
 		// TODO: gc's CGo implementation uses types such as `uint32` for enums
@@ -410,7 +431,7 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		typeSpec := &ast.TypeSpec{
 			Name: &ast.Ident{
 				NamePos: pos,
-				Name:    "C." + name,
+				Name:    "_Cgo_" + name,
 				Obj:     obj,
 			},
 			Assign: pos,
@@ -433,12 +454,12 @@ func (f *cgoFile) createASTNode(name string, c clangCursor) (ast.Node, any) {
 		}
 		obj := &ast.Object{
 			Kind: ast.Con,
-			Name: "C." + name,
+			Name: "_Cgo_" + name,
 		}
 		valueSpec := &ast.ValueSpec{
 			Names: []*ast.Ident{{
 				NamePos: pos,
-				Name:    "C." + name,
+				Name:    "_Cgo_" + name,
 				Obj:     obj,
 			}},
 			Values: []ast.Expr{expr},
@@ -724,27 +745,27 @@ 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:
-		typeName = "C.char"
+		typeName = "_Cgo_char"
 	case C.CXType_SChar:
-		typeName = "C.schar"
+		typeName = "_Cgo_schar"
 	case C.CXType_UChar:
-		typeName = "C.uchar"
+		typeName = "_Cgo_uchar"
 	case C.CXType_Short:
-		typeName = "C.short"
+		typeName = "_Cgo_short"
 	case C.CXType_UShort:
-		typeName = "C.ushort"
+		typeName = "_Cgo_ushort"
 	case C.CXType_Int:
-		typeName = "C.int"
+		typeName = "_Cgo_int"
 	case C.CXType_UInt:
-		typeName = "C.uint"
+		typeName = "_Cgo_uint"
 	case C.CXType_Long:
-		typeName = "C.long"
+		typeName = "_Cgo_long"
 	case C.CXType_ULong:
-		typeName = "C.ulong"
+		typeName = "_Cgo_ulong"
 	case C.CXType_LongLong:
-		typeName = "C.longlong"
+		typeName = "_Cgo_longlong"
 	case C.CXType_ULongLong:
-		typeName = "C.ulonglong"
+		typeName = "_Cgo_ulonglong"
 	case C.CXType_Bool:
 		typeName = "bool"
 	case C.CXType_Float, C.CXType_Double, C.CXType_LongDouble:
@@ -875,7 +896,7 @@ func (f *cgoFile) makeASTType(typ C.CXType, pos token.Pos) ast.Expr {
 		typeSpelling := getString(C.clang_getTypeSpelling(typ))
 		typeKindSpelling := getString(C.clang_getTypeKindSpelling(typ.kind))
 		f.addError(pos, fmt.Sprintf("unknown C type: %v (libclang type kind %s)", typeSpelling, typeKindSpelling))
-		typeName = "C.<unknown>"
+		typeName = "_Cgo_<unknown>"
 	}
 	return &ast.Ident{
 		NamePos: pos,
@@ -892,7 +913,7 @@ func (p *cgoPackage) getIntegerType(name string, cursor clangCursor) *ast.TypeSp
 	var goName string
 	typeSize := C.clang_Type_getSizeOf(underlyingType)
 	switch name {
-	case "C.char":
+	case "_Cgo_char":
 		if typeSize != 1 {
 			// This happens for some very special purpose architectures
 			// (DSPs etc.) that are not currently targeted.
@@ -905,7 +926,7 @@ func (p *cgoPackage) getIntegerType(name string, cursor clangCursor) *ast.TypeSp
 		case C.CXType_Char_U:
 			goName = "uint8"
 		}
-	case "C.schar", "C.short", "C.int", "C.long", "C.longlong":
+	case "_Cgo_schar", "_Cgo_short", "_Cgo_int", "_Cgo_long", "_Cgo_longlong":
 		switch typeSize {
 		case 1:
 			goName = "int8"
@@ -916,7 +937,7 @@ func (p *cgoPackage) getIntegerType(name string, cursor clangCursor) *ast.TypeSp
 		case 8:
 			goName = "int64"
 		}
-	case "C.uchar", "C.ushort", "C.uint", "C.ulong", "C.ulonglong":
+	case "_Cgo_uchar", "_Cgo_ushort", "_Cgo_uint", "_Cgo_ulong", "_Cgo_ulonglong":
 		switch typeSize {
 		case 1:
 			goName = "uint8"
@@ -1,4 +1,4 @@
-//go:build !byollvm && !llvm15 && !llvm16 && !llvm17
+//go:build !byollvm && llvm18

 package cgo

@@ -0,0 +1,15 @@
+//go:build !byollvm && !llvm15 && !llvm16 && !llvm17 && !llvm18
+
+package cgo
+
+/*
+#cgo linux        CFLAGS:  -I/usr/include/llvm-19 -I/usr/include/llvm-c-19 -I/usr/lib/llvm-19/include
+#cgo darwin,amd64 CFLAGS:  -I/usr/local/opt/llvm@19/include
+#cgo darwin,arm64 CFLAGS:  -I/opt/homebrew/opt/llvm@19/include
+#cgo freebsd      CFLAGS:  -I/usr/local/llvm19/include
+#cgo linux        LDFLAGS: -L/usr/lib/llvm-19/lib -lclang
+#cgo darwin,amd64 LDFLAGS: -L/usr/local/opt/llvm@19/lib -lclang
+#cgo darwin,arm64 LDFLAGS: -L/opt/homebrew/opt/llvm@19/lib -lclang
+#cgo freebsd      LDFLAGS: -L/usr/local/llvm19/lib -lclang
+*/
+import "C"
@@ -1,46 +1,54 @@
 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )
@@ -1,54 +1,62 @@
 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )

-const C.foo = 3
-const C.bar = C.foo
-const C.unreferenced = 4
-const C.referenced = C.unreferenced
-const C.fnlike_val = 5
-const C.square_val = (20 * 20)
-const C.add_val = (3 + 5)
+const _Cgo_foo = 3
+const _Cgo_bar = _Cgo_foo
+const _Cgo_unreferenced = 4
+const _Cgo_referenced = _Cgo_unreferenced
+const _Cgo_fnlike_val = 5
+const _Cgo_square_val = (20 * 20)
+const _Cgo_add_val = (3 + 5)
@@ -10,6 +10,11 @@ typedef struct {

 typedef someType noType; // undefined type

+// Some invalid noescape lines
+#cgo noescape
+#cgo noescape foo bar
+#cgo noescape unusedFunction
+
 #define SOME_CONST_1 5) // invalid const syntax
 #define SOME_CONST_2 6) // const not used (so no error)
 #define SOME_CONST_3 1234 // const too large for byte
@@ -1,78 +1,89 @@
 // CGo errors:
+//     testdata/errors.go:14:1: missing function name in #cgo noescape line
+//     testdata/errors.go:15:1: multiple function names in #cgo noescape line
 //     testdata/errors.go:4:2: warning: some warning
 //     testdata/errors.go:11:9: error: unknown type name 'someType'
-//     testdata/errors.go:26:5: warning: another warning
-//     testdata/errors.go:13:23: unexpected token ), expected end of expression
-//     testdata/errors.go:21:26: unexpected token ), expected end of expression
-//     testdata/errors.go:16:33: unexpected token ), expected end of expression
-//     testdata/errors.go:17:34: unexpected token ), expected end of expression
+//     testdata/errors.go:31:5: warning: another warning
+//     testdata/errors.go:18:23: unexpected token ), expected end of expression
+//     testdata/errors.go:26:26: unexpected token ), expected end of expression
+//     testdata/errors.go:21:33: unexpected token ), expected end of expression
+//     testdata/errors.go:22:34: unexpected token ), expected end of expression
 //     -: unexpected token INT, expected end of expression
-//     testdata/errors.go:30:35: unexpected number of parameters: expected 2, got 3
-//     testdata/errors.go:31:31: unexpected number of parameters: expected 2, got 1
+//     testdata/errors.go:35:35: unexpected number of parameters: expected 2, got 3
+//     testdata/errors.go:36:31: unexpected number of parameters: expected 2, got 1
+//     testdata/errors.go:3:1: function "unusedFunction" in #cgo noescape line is not used

 // Type checking errors after CGo processing:
-//     testdata/errors.go:102: cannot use 2 << 10 (untyped int constant 2048) as C.char value in variable declaration (overflows)
+//     testdata/errors.go:102: cannot use 2 << 10 (untyped int constant 2048) as _Cgo_char value in variable declaration (overflows)
 //     testdata/errors.go:105: unknown field z in struct literal
-//     testdata/errors.go:108: undefined: 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: undefined: C.SOME_CONST_4
-//     testdata/errors.go:114: undefined: C.SOME_CONST_b
-//     testdata/errors.go:116: undefined: C.SOME_CONST_startspace
-//     testdata/errors.go:119: undefined: C.SOME_PARAM_CONST_invalid
-//     testdata/errors.go:122: undefined: C.add_toomuch
-//     testdata/errors.go:123: undefined: C.add_toolittle
+//     testdata/errors.go:108: undefined: _Cgo_SOME_CONST_1
+//     testdata/errors.go:110: cannot use _Cgo_SOME_CONST_3 (untyped int constant 1234) as byte value in variable declaration (overflows)
+//     testdata/errors.go:112: undefined: _Cgo_SOME_CONST_4
+//     testdata/errors.go:114: undefined: _Cgo_SOME_CONST_b
+//     testdata/errors.go:116: undefined: _Cgo_SOME_CONST_startspace
+//     testdata/errors.go:119: undefined: _Cgo_SOME_PARAM_CONST_invalid
+//     testdata/errors.go:122: undefined: _Cgo_add_toomuch
+//     testdata/errors.go:123: undefined: _Cgo_add_toolittle

 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )
-type C.struct_point_t struct {
-	x C.int
-	y C.int
+type _Cgo_struct_point_t struct {
+	x _Cgo_int
+	y _Cgo_int
 }
-type C.point_t = C.struct_point_t
+type _Cgo_point_t = _Cgo_struct_point_t

-const C.SOME_CONST_3 = 1234
-const C.SOME_PARAM_CONST_valid = 3 + 4
+const _Cgo_SOME_CONST_3 = 1234
+const _Cgo_SOME_PARAM_CONST_valid = 3 + 4
@@ -5,50 +5,58 @@

 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )

-const C.BAR = 3
-const C.FOO_H = 1
+const _Cgo_BAR = 3
+const _Cgo_FOO_H = 1
@@ -9,6 +9,10 @@ static void staticfunc(int x);

 // Global variable signatures.
 extern int someValue;
+
+void notEscapingFunction(int *a);
+
+#cgo noescape notEscapingFunction
 */
 import "C"

@@ -18,6 +22,7 @@ func accessFunctions() {
 	C.variadic0()
 	C.variadic2(3, 5)
 	C.staticfunc(3)
+	C.notEscapingFunction(nil)
 }

 func accessGlobals() {
@@ -1,71 +1,84 @@
 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )

 //export foo
-func C.foo(a C.int, b C.int) C.int
+func _Cgo_foo(a _Cgo_int, b _Cgo_int) _Cgo_int

-var C.foo$funcaddr unsafe.Pointer
+var _Cgo_foo$funcaddr unsafe.Pointer

 //export variadic0
 //go:variadic
-func C.variadic0()
+func _Cgo_variadic0()

-var C.variadic0$funcaddr unsafe.Pointer
+var _Cgo_variadic0$funcaddr unsafe.Pointer

 //export variadic2
 //go:variadic
-func C.variadic2(x C.int, y C.int)
+func _Cgo_variadic2(x _Cgo_int, y _Cgo_int)

-var C.variadic2$funcaddr unsafe.Pointer
+var _Cgo_variadic2$funcaddr unsafe.Pointer

 //export _Cgo_static_173c95a79b6df1980521_staticfunc
-func C.staticfunc!symbols.go(x C.int)
+func _Cgo_staticfunc!symbols.go(x _Cgo_int)

-var C.staticfunc!symbols.go$funcaddr unsafe.Pointer
+var _Cgo_staticfunc!symbols.go$funcaddr unsafe.Pointer

+//export notEscapingFunction
+//go:noescape
+func _Cgo_notEscapingFunction(a *_Cgo_int)
+
+var _Cgo_notEscapingFunction$funcaddr unsafe.Pointer
 //go:extern someValue
-var C.someValue C.int
+var _Cgo_someValue _Cgo_int
@@ -1,154 +1,166 @@
 package main

+import "syscall"
 import "unsafe"

 var _ unsafe.Pointer

-//go:linkname C.CString runtime.cgo_CString
-func C.CString(string) *C.char
+//go:linkname _Cgo_CString runtime.cgo_CString
+func _Cgo_CString(string) *_Cgo_char

-//go:linkname C.GoString runtime.cgo_GoString
-func C.GoString(*C.char) string
+//go:linkname _Cgo_GoString runtime.cgo_GoString
+func _Cgo_GoString(*_Cgo_char) string

-//go:linkname C.__GoStringN runtime.cgo_GoStringN
-func C.__GoStringN(*C.char, uintptr) string
+//go:linkname _Cgo___GoStringN runtime.cgo_GoStringN
+func _Cgo___GoStringN(*_Cgo_char, uintptr) string

-func C.GoStringN(cstr *C.char, length C.int) string {
-	return C.__GoStringN(cstr, uintptr(length))
+func _Cgo_GoStringN(cstr *_Cgo_char, length _Cgo_int) string {
+	return _Cgo___GoStringN(cstr, uintptr(length))
 }

-//go:linkname C.__GoBytes runtime.cgo_GoBytes
-func C.__GoBytes(unsafe.Pointer, uintptr) []byte
+//go:linkname _Cgo___GoBytes runtime.cgo_GoBytes
+func _Cgo___GoBytes(unsafe.Pointer, uintptr) []byte

-func C.GoBytes(ptr unsafe.Pointer, length C.int) []byte {
-	return C.__GoBytes(ptr, uintptr(length))
+func _Cgo_GoBytes(ptr unsafe.Pointer, length _Cgo_int) []byte {
+	return _Cgo___GoBytes(ptr, uintptr(length))
 }

-//go:linkname C.__CBytes runtime.cgo_CBytes
-func C.__CBytes([]byte) unsafe.Pointer
+//go:linkname _Cgo___CBytes runtime.cgo_CBytes
+func _Cgo___CBytes([]byte) unsafe.Pointer

-func C.CBytes(b []byte) unsafe.Pointer {
-	return C.__CBytes(b)
+func _Cgo_CBytes(b []byte) unsafe.Pointer {
+	return _Cgo___CBytes(b)
+}
+
+//go:linkname _Cgo___get_errno_num runtime.cgo_errno
+func _Cgo___get_errno_num() uintptr
+
+func _Cgo___get_errno() error {
+	return syscall.Errno(_Cgo___get_errno_num())
 }

 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_char      uint8
+	_Cgo_schar     int8
+	_Cgo_uchar     uint8
+	_Cgo_short     int16
+	_Cgo_ushort    uint16
+	_Cgo_int       int32
+	_Cgo_uint      uint32
+	_Cgo_long      int32
+	_Cgo_ulong     uint32
+	_Cgo_longlong  int64
+	_Cgo_ulonglong uint64
 )
-type C.myint = C.int
-type C.struct_point2d_t struct {
-	x C.int
-	y C.int
+type _Cgo_myint = _Cgo_int
+type _Cgo_struct_point2d_t struct {
+	x _Cgo_int
+	y _Cgo_int
 }
-type C.point2d_t = C.struct_point2d_t
-type C.struct_point3d struct {
-	x C.int
-	y C.int
-	z C.int
+type _Cgo_point2d_t = _Cgo_struct_point2d_t
+type _Cgo_struct_point3d struct {
+	x _Cgo_int
+	y _Cgo_int
+	z _Cgo_int
 }
-type C.point3d_t = C.struct_point3d
-type C.struct_type1 struct {
-	_type   C.int
-	__type  C.int
-	___type C.int
+type _Cgo_point3d_t = _Cgo_struct_point3d
+type _Cgo_struct_type1 struct {
+	_type   _Cgo_int
+	__type  _Cgo_int
+	___type _Cgo_int
 }
-type C.struct_type2 struct{ _type C.int }
-type C.union_union1_t struct{ i C.int }
-type C.union1_t = C.union_union1_t
-type C.union_union3_t struct{ $union uint64 }
+type _Cgo_struct_type2 struct{ _type _Cgo_int }
+type _Cgo_union_union1_t struct{ i _Cgo_int }
+type _Cgo_union1_t = _Cgo_union_union1_t
+type _Cgo_union_union3_t struct{ $union uint64 }

-func (union *C.union_union3_t) unionfield_i() *C.int { return (*C.int)(unsafe.Pointer(&union.$union)) }
-func (union *C.union_union3_t) unionfield_d() *float64 {
+func (union *_Cgo_union_union3_t) unionfield_i() *_Cgo_int {
+	return (*_Cgo_int)(unsafe.Pointer(&union.$union))
+}
+func (union *_Cgo_union_union3_t) unionfield_d() *float64 {
 	return (*float64)(unsafe.Pointer(&union.$union))
 }
-func (union *C.union_union3_t) unionfield_s() *C.short {
-	return (*C.short)(unsafe.Pointer(&union.$union))
+func (union *_Cgo_union_union3_t) unionfield_s() *_Cgo_short {
+	return (*_Cgo_short)(unsafe.Pointer(&union.$union))
 }

-type C.union3_t = C.union_union3_t
-type C.union_union2d struct{ $union [2]uint64 }
+type _Cgo_union3_t = _Cgo_union_union3_t
+type _Cgo_union_union2d struct{ $union [2]uint64 }

-func (union *C.union_union2d) unionfield_i() *C.int { return (*C.int)(unsafe.Pointer(&union.$union)) }
-func (union *C.union_union2d) unionfield_d() *[2]float64 {
+func (union *_Cgo_union_union2d) unionfield_i() *_Cgo_int {
+	return (*_Cgo_int)(unsafe.Pointer(&union.$union))
+}
+func (union *_Cgo_union_union2d) unionfield_d() *[2]float64 {
 	return (*[2]float64)(unsafe.Pointer(&union.$union))
 }

-type C.union2d_t = C.union_union2d
-type C.union_unionarray_t struct{ arr [10]C.uchar }
-type C.unionarray_t = C.union_unionarray_t
-type C._Ctype_union___0 struct{ $union [3]uint32 }
+type _Cgo_union2d_t = _Cgo_union_union2d
+type _Cgo_union_unionarray_t struct{ arr [10]_Cgo_uchar }
+type _Cgo_unionarray_t = _Cgo_union_unionarray_t
+type _Cgo__Ctype_union___0 struct{ $union [3]uint32 }

-func (union *C._Ctype_union___0) unionfield_area() *C.point2d_t {
-	return (*C.point2d_t)(unsafe.Pointer(&union.$union))
+func (union *_Cgo__Ctype_union___0) unionfield_area() *_Cgo_point2d_t {
+	return (*_Cgo_point2d_t)(unsafe.Pointer(&union.$union))
 }
-func (union *C._Ctype_union___0) unionfield_solid() *C.point3d_t {
-	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
+func (union *_Cgo__Ctype_union___0) unionfield_solid() *_Cgo_point3d_t {
+	return (*_Cgo_point3d_t)(unsafe.Pointer(&union.$union))
 }

-type C.struct_struct_nested_t struct {
-	begin C.point2d_t
-	end   C.point2d_t
-	tag   C.int
+type _Cgo_struct_struct_nested_t struct {
+	begin _Cgo_point2d_t
+	end   _Cgo_point2d_t
+	tag   _Cgo_int

-	coord C._Ctype_union___0
+	coord _Cgo__Ctype_union___0
 }
-type C.struct_nested_t = C.struct_struct_nested_t
-type C.union_union_nested_t struct{ $union [2]uint64 }
+type _Cgo_struct_nested_t = _Cgo_struct_struct_nested_t
+type _Cgo_union_union_nested_t struct{ $union [2]uint64 }

-func (union *C.union_union_nested_t) unionfield_point() *C.point3d_t {
-	return (*C.point3d_t)(unsafe.Pointer(&union.$union))
+func (union *_Cgo_union_union_nested_t) unionfield_point() *_Cgo_point3d_t {
+	return (*_Cgo_point3d_t)(unsafe.Pointer(&union.$union))
 }
-func (union *C.union_union_nested_t) unionfield_array() *C.unionarray_t {
-	return (*C.unionarray_t)(unsafe.Pointer(&union.$union))
+func (union *_Cgo_union_union_nested_t) unionfield_array() *_Cgo_unionarray_t {
+	return (*_Cgo_unionarray_t)(unsafe.Pointer(&union.$union))
 }
-func (union *C.union_union_nested_t) unionfield_thing() *C.union3_t {
-	return (*C.union3_t)(unsafe.Pointer(&union.$union))
+func (union *_Cgo_union_union_nested_t) unionfield_thing() *_Cgo_union3_t {
+	return (*_Cgo_union3_t)(unsafe.Pointer(&union.$union))
 }

-type C.union_nested_t = C.union_union_nested_t
-type C.enum_option = C.int
-type C.option_t = C.enum_option
-type C.enum_option2_t = C.uint
-type C.option2_t = C.enum_option2_t
-type C.struct_types_t struct {
+type _Cgo_union_nested_t = _Cgo_union_union_nested_t
+type _Cgo_enum_option = _Cgo_int
+type _Cgo_option_t = _Cgo_enum_option
+type _Cgo_enum_option2_t = _Cgo_uint
+type _Cgo_option2_t = _Cgo_enum_option2_t
+type _Cgo_struct_types_t struct {
 	f   float32
 	d   float64
-	ptr *C.int
+	ptr *_Cgo_int
 }
-type C.types_t = C.struct_types_t
-type C.myIntArray = [10]C.int
-type C.struct_bitfield_t struct {
-	start        C.uchar
-	__bitfield_1 C.uchar
+type _Cgo_types_t = _Cgo_struct_types_t
+type _Cgo_myIntArray = [10]_Cgo_int
+type _Cgo_struct_bitfield_t struct {
+	start        _Cgo_uchar
+	__bitfield_1 _Cgo_uchar

-	d C.uchar
-	e C.uchar
+	d _Cgo_uchar
+	e _Cgo_uchar
 }

-func (s *C.struct_bitfield_t) bitfield_a() C.uchar { return s.__bitfield_1 & 0x1f }
-func (s *C.struct_bitfield_t) set_bitfield_a(value C.uchar) {
+func (s *_Cgo_struct_bitfield_t) bitfield_a() _Cgo_uchar { return s.__bitfield_1 & 0x1f }
+func (s *_Cgo_struct_bitfield_t) set_bitfield_a(value _Cgo_uchar) {
 	s.__bitfield_1 = s.__bitfield_1&^0x1f | value&0x1f<<0
 }
-func (s *C.struct_bitfield_t) bitfield_b() C.uchar {
+func (s *_Cgo_struct_bitfield_t) bitfield_b() _Cgo_uchar {
 	return s.__bitfield_1 >> 5 & 0x1
 }
-func (s *C.struct_bitfield_t) set_bitfield_b(value C.uchar) {
+func (s *_Cgo_struct_bitfield_t) set_bitfield_b(value _Cgo_uchar) {
 	s.__bitfield_1 = s.__bitfield_1&^0x20 | value&0x1<<5
 }
-func (s *C.struct_bitfield_t) bitfield_c() C.uchar {
+func (s *_Cgo_struct_bitfield_t) bitfield_c() _Cgo_uchar {
 	return s.__bitfield_1 >> 6
 }
-func (s *C.struct_bitfield_t) set_bitfield_c(value C.uchar,
+func (s *_Cgo_struct_bitfield_t) set_bitfield_c(value _Cgo_uchar,

 ) { s.__bitfield_1 = s.__bitfield_1&0x3f | value<<6 }

-type C.bitfield_t = C.struct_bitfield_t
+type _Cgo_bitfield_t = _Cgo_struct_bitfield_t
@@ -331,6 +331,7 @@ func (c *Config) CFlags(libclang bool) []string {
 			"-isystem", filepath.Join(path, "include"),
 			"-isystem", filepath.Join(picolibcDir, "include"),
 			"-isystem", filepath.Join(picolibcDir, "tinystdio"),
+			"-D__PICOLIBC_ERRNO_FUNCTION=__errno_location",
 		)
 	case "musl":
 		root := goenv.Get("TINYGOROOT")
@@ -340,6 +341,7 @@ func (c *Config) CFlags(libclang bool) []string {
 			"-nostdlibinc",
 			"-isystem", filepath.Join(path, "include"),
 			"-isystem", filepath.Join(root, "lib", "musl", "arch", arch),
+			"-isystem", filepath.Join(root, "lib", "musl", "arch", "generic"),
 			"-isystem", filepath.Join(root, "lib", "musl", "include"),
 		)
 	case "wasi-libc":
@@ -8,11 +8,11 @@ import (
 )

 var (
-	validBuildModeOptions     = []string{"default", "c-shared"}
+	validBuildModeOptions     = []string{"default", "c-shared", "wasi-legacy"}
 	validGCOptions            = []string{"none", "leaking", "conservative", "custom", "precise"}
 	validSchedulerOptions     = []string{"none", "tasks", "asyncify"}
 	validSerialOptions        = []string{"none", "uart", "usb", "rtt"}
-	validPrintSizeOptions     = []string{"none", "short", "full"}
+	validPrintSizeOptions     = []string{"none", "short", "full", "html"}
 	validPanicStrategyOptions = []string{"print", "trap"}
 	validOptOptions           = []string{"none", "0", "1", "2", "s", "z"}
 )
@@ -11,7 +11,7 @@ func TestVerifyOptions(t *testing.T) {

 	expectedGCError := errors.New(`invalid gc option 'incorrect': valid values are none, leaking, conservative, custom, precise`)
 	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`)
+	expectedPrintSizeError := errors.New(`invalid size option 'incorrect': valid values are none, short, full, html`)
 	expectedPanicStrategyError := errors.New(`invalid panic option 'incorrect': valid values are print, trap`)

 	testCases := []struct {
@@ -46,6 +46,7 @@ type TargetSpec struct {
 	LinkerScript     string   `json:"linkerscript,omitempty"`
 	ExtraFiles       []string `json:"extra-files,omitempty"`
 	RP2040BootPatch  *bool    `json:"rp2040-boot-patch,omitempty"` // Patch RP2040 2nd stage bootloader checksum
+	BootPatches      []string `json:"boot-patches,omitempty"`      // Bootloader patches to be applied in the order they appear.
 	Emulator         string   `json:"emulator,omitempty"`
 	FlashCommand     string   `json:"flash-command,omitempty"`
 	GDB              []string `json:"gdb,omitempty"`
@@ -327,14 +328,14 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
 		spec.CPU = "generic"
 		llvmarch = "aarch64"
 		if options.GOOS == "darwin" {
-			spec.Features = "+fp-armv8,+neon"
+			spec.Features = "+ete,+fp-armv8,+neon,+trbe,+v8a"
 			// Looks like Apple prefers to call this architecture ARM64
 			// instead of AArch64.
 			llvmarch = "arm64"
 		} else if options.GOOS == "windows" {
-			spec.Features = "+fp-armv8,+neon,-fmv"
+			spec.Features = "+ete,+fp-armv8,+neon,+trbe,+v8a,-fmv"
 		} else { // linux
-			spec.Features = "+fp-armv8,+neon,-fmv,-outline-atomics"
+			spec.Features = "+ete,+fp-armv8,+neon,+trbe,+v8a,-fmv,-outline-atomics"
 		}
 	case "mips", "mipsle":
 		spec.CPU = "mips32"
@@ -355,15 +356,7 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
 			return nil, fmt.Errorf("invalid GOMIPS=%s: must be hardfloat or softfloat", options.GOMIPS)
 		}
 	case "wasm":
-		llvmarch = "wasm32"
-		spec.CPU = "generic"
-		spec.Features = "+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext"
-		spec.BuildTags = append(spec.BuildTags, "tinygo.wasm")
-		spec.CFlags = append(spec.CFlags,
-			"-mbulk-memory",
-			"-mnontrapping-fptoint",
-			"-msign-ext",
-		)
+		return nil, fmt.Errorf("GOARCH=wasm but GOOS is unset. Please set GOOS to wasm, wasip1, or wasip2.")
 	default:
 		return nil, fmt.Errorf("unknown GOARCH=%s", options.GOARCH)
 	}
@@ -390,6 +383,7 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
 			"-platform_version", "macos", platformVersion, platformVersion,
 		)
 		spec.ExtraFiles = append(spec.ExtraFiles,
+			"src/internal/futex/futex_darwin.c",
 			"src/runtime/os_darwin.c",
 			"src/runtime/runtime_unix.c",
 			"src/runtime/signal.c")
@@ -413,6 +407,7 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
 			spec.CFlags = append(spec.CFlags, "-mno-outline-atomics")
 		}
 		spec.ExtraFiles = append(spec.ExtraFiles,
+			"src/internal/futex/futex_linux.c",
 			"src/runtime/runtime_unix.c",
 			"src/runtime/signal.c")
 	case "windows":
@@ -441,23 +436,8 @@ func defaultTarget(options *Options) (*TargetSpec, error) {
 			"--no-insert-timestamp",
 			"--no-dynamicbase",
 		)
-	case "wasip1":
-		spec.GC = "" // use default GC
-		spec.Scheduler = "asyncify"
-		spec.Linker = "wasm-ld"
-		spec.RTLib = "compiler-rt"
-		spec.Libc = "wasi-libc"
-		spec.DefaultStackSize = 1024 * 64 // 64kB
-		spec.LDFlags = append(spec.LDFlags,
-			"--stack-first",
-			"--no-demangle",
-		)
-		spec.Emulator = "wasmtime run --dir={tmpDir}::/tmp {}"
-		spec.ExtraFiles = append(spec.ExtraFiles,
-			"src/runtime/asm_tinygowasm.S",
-			"src/internal/task/task_asyncify_wasm.S",
-		)
-		llvmos = "wasi"
+	case "wasm", "wasip1", "wasip2":
+		return nil, fmt.Errorf("GOOS=%s but GOARCH is unset. Please set GOARCH to wasm", options.GOOS)
 	default:
 		return nil, fmt.Errorf("unknown GOOS=%s", options.GOOS)
 	}
@@ -18,11 +18,12 @@ var stdlibAliases = map[string]string{
 	// crypto packages
 	"crypto/ed25519/internal/edwards25519/field.feMul": "crypto/ed25519/internal/edwards25519/field.feMulGeneric",
 	"crypto/internal/edwards25519/field.feSquare":      "crypto/ed25519/internal/edwards25519/field.feSquareGeneric",
-	"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",
+	"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",
+	"internal/chacha8rand.block": "internal/chacha8rand.block_generic",

 	// AES
 	"crypto/aes.decryptBlockAsm": "crypto/aes.decryptBlock",
@@ -19,8 +19,9 @@ const maxFieldsPerParam = 3
 // useful while declaring or defining a function.
 type paramInfo struct {
 	llvmType llvm.Type
-	name     string // name, possibly with suffixes for e.g. struct fields
-	elemSize uint64 // size of pointer element type, or 0 if this isn't a pointer
+	name     string     // name, possibly with suffixes for e.g. struct fields
+	elemSize uint64     // size of pointer element type, or 0 if this isn't a pointer
+	flags    paramFlags // extra flags for this parameter
 }

 // paramFlags identifies parameter attributes for flags. Most importantly, it
@@ -28,9 +29,9 @@ type paramInfo struct {
 type paramFlags uint8

 const (
-	// Parameter may have the deferenceable_or_null attribute. This attribute
-	// cannot be applied to unsafe.Pointer and to the data pointer of slices.
-	paramIsDeferenceableOrNull = 1 << iota
+	// Whether this is a full or partial Go parameter (int, slice, etc).
+	// The extra context parameter is not a Go parameter.
+	paramIsGoParam = 1 << iota
 )

 // createRuntimeCallCommon creates a runtime call. Use createRuntimeCall or
@@ -195,6 +196,7 @@ func (c *compilerContext) getParamInfo(t llvm.Type, name string, goType types.Ty
 	info := paramInfo{
 		llvmType: t,
 		name:     name,
+		flags:    paramIsGoParam,
 	}
 	if goType != nil {
 		switch underlying := goType.Underlying().(type) {
@@ -4,7 +4,9 @@ package compiler
 // or pseudo-operations that are lowered during goroutine lowering.

 import (
+	"fmt"
 	"go/types"
+	"math"

 	"github.com/tinygo-org/tinygo/compiler/llvmutil"
 	"golang.org/x/tools/go/ssa"
@@ -41,17 +43,17 @@ func (b *builder) createChanSend(instr *ssa.Send) {
 		b.CreateStore(chanValue, valueAlloca)
 	}

-	// Allocate blockedlist buffer.
-	channelBlockedList := b.getLLVMRuntimeType("channelBlockedList")
-	channelBlockedListAlloca, channelBlockedListAllocaSize := b.createTemporaryAlloca(channelBlockedList, "chan.blockedList")
+	// Allocate buffer for the channel operation.
+	channelOp := b.getLLVMRuntimeType("channelOp")
+	channelOpAlloca, channelOpAllocaSize := b.createTemporaryAlloca(channelOp, "chan.op")

 	// Do the send.
-	b.createRuntimeCall("chanSend", []llvm.Value{ch, valueAlloca, channelBlockedListAlloca}, "")
+	b.createRuntimeCall("chanSend", []llvm.Value{ch, valueAlloca, channelOpAlloca}, "")

 	// End the lifetime of the allocas.
 	// This also works around a bug in CoroSplit, at least in LLVM 8:
 	// https://bugs.llvm.org/show_bug.cgi?id=41742
-	b.emitLifetimeEnd(channelBlockedListAlloca, channelBlockedListAllocaSize)
+	b.emitLifetimeEnd(channelOpAlloca, channelOpAllocaSize)
 	if !isZeroSize {
 		b.emitLifetimeEnd(valueAlloca, valueAllocaSize)
 	}
@@ -72,12 +74,12 @@ func (b *builder) createChanRecv(unop *ssa.UnOp) llvm.Value {
 		valueAlloca, valueAllocaSize = b.createTemporaryAlloca(valueType, "chan.value")
 	}

-	// Allocate blockedlist buffer.
-	channelBlockedList := b.getLLVMRuntimeType("channelBlockedList")
-	channelBlockedListAlloca, channelBlockedListAllocaSize := b.createTemporaryAlloca(channelBlockedList, "chan.blockedList")
+	// Allocate buffer for the channel operation.
+	channelOp := b.getLLVMRuntimeType("channelOp")
+	channelOpAlloca, channelOpAllocaSize := b.createTemporaryAlloca(channelOp, "chan.op")

 	// Do the receive.
-	commaOk := b.createRuntimeCall("chanRecv", []llvm.Value{ch, valueAlloca, channelBlockedListAlloca}, "")
+	commaOk := b.createRuntimeCall("chanRecv", []llvm.Value{ch, valueAlloca, channelOpAlloca}, "")
 	var received llvm.Value
 	if isZeroSize {
 		received = llvm.ConstNull(valueType)
@@ -85,7 +87,7 @@ func (b *builder) createChanRecv(unop *ssa.UnOp) llvm.Value {
 		received = b.CreateLoad(valueType, valueAlloca, "chan.received")
 		b.emitLifetimeEnd(valueAlloca, valueAllocaSize)
 	}
-	b.emitLifetimeEnd(channelBlockedListAlloca, channelBlockedListAllocaSize)
+	b.emitLifetimeEnd(channelOpAlloca, channelOpAllocaSize)

 	if unop.CommaOk {
 		tuple := llvm.Undef(b.ctx.StructType([]llvm.Type{valueType, b.ctx.Int1Type()}, false))
@@ -124,6 +126,20 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 		}
 	}

+	const maxSelectStates = math.MaxUint32 >> 2
+	if len(expr.States) > maxSelectStates {
+		// The runtime code assumes that the number of state must fit in 30 bits
+		// (so the select index can be stored in a uint32 with two bits reserved
+		// for other purposes). It seems unlikely that a real program would have
+		// that many states, but we check for this case anyway to be sure.
+		// We use a uint32 (and not a uintptr or uint64) to avoid 64-bit atomic
+		// operations which aren't available everywhere.
+		b.addError(expr.Pos(), fmt.Sprintf("too many select states: got %d but the maximum supported number is %d", len(expr.States), maxSelectStates))
+
+		// Continue as usual (we'll generate broken code but the error will
+		// prevent the compilation to complete).
+	}
+
 	// This code create a (stack-allocated) slice containing all the select
 	// cases and then calls runtime.chanSelect to perform the actual select
 	// statement.
@@ -198,10 +214,10 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 	if expr.Blocking {
 		// Stack-allocate operation structures.
 		// If these were simply created as a slice, they would heap-allocate.
-		chBlockAllocaType := llvm.ArrayType(b.getLLVMRuntimeType("channelBlockedList"), len(selectStates))
-		chBlockAlloca, chBlockSize := b.createTemporaryAlloca(chBlockAllocaType, "select.block.alloca")
-		chBlockLen := llvm.ConstInt(b.uintptrType, uint64(len(selectStates)), false)
-		chBlockPtr := b.CreateGEP(chBlockAllocaType, chBlockAlloca, []llvm.Value{
+		opsAllocaType := llvm.ArrayType(b.getLLVMRuntimeType("channelOp"), len(selectStates))
+		opsAlloca, opsSize := b.createTemporaryAlloca(opsAllocaType, "select.block.alloca")
+		opsLen := llvm.ConstInt(b.uintptrType, uint64(len(selectStates)), false)
+		opsPtr := b.CreateGEP(opsAllocaType, opsAlloca, []llvm.Value{
 			llvm.ConstInt(b.ctx.Int32Type(), 0, false),
 			llvm.ConstInt(b.ctx.Int32Type(), 0, false),
 		}, "select.block")
@@ -209,15 +225,18 @@ func (b *builder) createSelect(expr *ssa.Select) llvm.Value {
 		results = b.createRuntimeCall("chanSelect", []llvm.Value{
 			recvbuf,
 			statesPtr, statesLen, statesLen, // []chanSelectState
-			chBlockPtr, chBlockLen, chBlockLen, // []channelBlockList
+			opsPtr, opsLen, opsLen, // []channelOp
 		}, "select.result")

 		// Terminate the lifetime of the operation structures.
-		b.emitLifetimeEnd(chBlockAlloca, chBlockSize)
+		b.emitLifetimeEnd(opsAlloca, opsSize)
 	} else {
-		results = b.createRuntimeCall("tryChanSelect", []llvm.Value{
+		opsPtr := llvm.ConstNull(b.dataPtrType)
+		opsLen := llvm.ConstInt(b.uintptrType, 0, false)
+		results = b.createRuntimeCall("chanSelect", []llvm.Value{
 			recvbuf,
 			statesPtr, statesLen, statesLen, // []chanSelectState
+			opsPtr, opsLen, opsLen, // []channelOp (nil slice)
 		}, "select.result")
 	}

@@ -1686,6 +1686,7 @@ func (b *builder) createBuiltin(argTypes []types.Type, argValues []llvm.Value, c
 		b.createRuntimeInvoke("_panic", argValues, "")
 		return llvm.Value{}, nil
 	case "print", "println":
+		b.createRuntimeCall("printlock", nil, "")
 		for i, value := range argValues {
 			if i >= 1 && callName == "println" {
 				b.createRuntimeCall("printspace", nil, "")
@@ -1746,6 +1747,7 @@ func (b *builder) createBuiltin(argTypes []types.Type, argValues []llvm.Value, c
 		if callName == "println" {
 			b.createRuntimeCall("printnl", nil, "")
 		}
+		b.createRuntimeCall("printunlock", nil, "")
 		return llvm.Value{}, nil // print() or println() returns void
 	case "real":
 		cplx := argValues[0]
@@ -161,7 +161,7 @@ str x2, [x1, #8]
 mov x0, #0
 1:
 `
-		constraints = "={x0},{x1},~{x1},~{x2},~{x3},~{x4},~{x5},~{x6},~{x7},~{x8},~{x9},~{x10},~{x11},~{x12},~{x13},~{x14},~{x15},~{x16},~{x17},~{x19},~{x20},~{x21},~{x22},~{x23},~{x24},~{x25},~{x26},~{x27},~{x28},~{lr},~{q0},~{q1},~{q2},~{q3},~{q4},~{q5},~{q6},~{q7},~{q8},~{q9},~{q10},~{q11},~{q12},~{q13},~{q14},~{q15},~{q16},~{q17},~{q18},~{q19},~{q20},~{q21},~{q22},~{q23},~{q24},~{q25},~{q26},~{q27},~{q28},~{q29},~{q30},~{nzcv},~{ffr},~{vg},~{memory}"
+		constraints = "={x0},{x1},~{x1},~{x2},~{x3},~{x4},~{x5},~{x6},~{x7},~{x8},~{x9},~{x10},~{x11},~{x12},~{x13},~{x14},~{x15},~{x16},~{x17},~{x19},~{x20},~{x21},~{x22},~{x23},~{x24},~{x25},~{x26},~{x27},~{x28},~{lr},~{q0},~{q1},~{q2},~{q3},~{q4},~{q5},~{q6},~{q7},~{q8},~{q9},~{q10},~{q11},~{q12},~{q13},~{q14},~{q15},~{q16},~{q17},~{q18},~{q19},~{q20},~{q21},~{q22},~{q23},~{q24},~{q25},~{q26},~{q27},~{q28},~{q29},~{q30},~{nzcv},~{ffr},~{memory}"
 		if b.GOOS != "darwin" && b.GOOS != "windows" {
 			// These registers cause the following warning when compiling for
 			// MacOS and Windows:
@@ -33,6 +33,7 @@ type functionInfo struct {
 	exported      bool       // go:export, CGo
 	interrupt     bool       // go:interrupt
 	nobounds      bool       // go:nobounds
+	noescape      bool       // go:noescape
 	variadic      bool       // go:variadic (CGo only)
 	inline        inlineType // go:inline
 }
@@ -127,11 +128,20 @@ func (c *compilerContext) getFunction(fn *ssa.Function) (llvm.Type, llvm.Value)
 	c.addStandardDeclaredAttributes(llvmFn)

 	dereferenceableOrNullKind := llvm.AttributeKindID("dereferenceable_or_null")
-	for i, info := range paramInfos {
-		if info.elemSize != 0 {
-			dereferenceableOrNull := c.ctx.CreateEnumAttribute(dereferenceableOrNullKind, info.elemSize)
+	for i, paramInfo := range paramInfos {
+		if paramInfo.elemSize != 0 {
+			dereferenceableOrNull := c.ctx.CreateEnumAttribute(dereferenceableOrNullKind, paramInfo.elemSize)
 			llvmFn.AddAttributeAtIndex(i+1, dereferenceableOrNull)
 		}
+		if info.noescape && paramInfo.flags&paramIsGoParam != 0 && paramInfo.llvmType.TypeKind() == llvm.PointerTypeKind {
+			// Parameters to functions with a //go:noescape parameter should get
+			// the nocapture attribute. However, the context parameter should
+			// not.
+			// (It may be safe to add the nocapture parameter to the context
+			// parameter, but I'd like to stay on the safe side here).
+			nocapture := c.ctx.CreateEnumAttribute(llvm.AttributeKindID("nocapture"), 0)
+			llvmFn.AddAttributeAtIndex(i+1, nocapture)
+		}
 	}

 	// Set a number of function or parameter attributes, depending on the
@@ -221,6 +231,15 @@ func (c *compilerContext) getFunction(fn *ssa.Function) (llvm.Type, llvm.Value)
 		}
 	}

+	// Build the function if needed.
+	c.maybeCreateSyntheticFunction(fn, llvmFn)
+
+	return fnType, llvmFn
+}
+
+// If this is a synthetic function (such as a generic function or a wrapper),
+// create it now.
+func (c *compilerContext) maybeCreateSyntheticFunction(fn *ssa.Function, llvmFn llvm.Value) {
 	// Synthetic functions are functions that do not appear in the source code,
 	// they are artificially constructed. Usually they are wrapper functions
 	// that are not referenced anywhere except in a SSA call instruction so
@@ -228,6 +247,10 @@ func (c *compilerContext) getFunction(fn *ssa.Function) (llvm.Type, llvm.Value)
 	// 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" && fn.Synthetic != "generic function" && fn.Synthetic != "range-over-func yield" {
+		if len(fn.Blocks) == 0 {
+			c.addError(fn.Pos(), "missing function body")
+			return
+		}
 		irbuilder := c.ctx.NewBuilder()
 		b := newBuilder(c, irbuilder, fn)
 		b.createFunction()
@@ -235,8 +258,6 @@ func (c *compilerContext) getFunction(fn *ssa.Function) (llvm.Type, llvm.Value)
 		llvmFn.SetLinkage(llvm.LinkOnceODRLinkage)
 		llvmFn.SetUnnamedAddr(true)
 	}
-
-	return fnType, llvmFn
 }

 // getFunctionInfo returns information about a function that is not directly
@@ -262,6 +283,11 @@ func (c *compilerContext) getFunctionInfo(f *ssa.Function) functionInfo {
 		info.wasmName = "_start"
 		info.exported = true
 	}
+	if info.linkName == "runtime.wasmEntryLegacy" && c.BuildMode == "wasi-legacy" {
+		info.linkName = "_start"
+		info.wasmName = "_start"
+		info.exported = true
+	}

 	// Check for //go: pragmas, which may change the link name (among others).
 	c.parsePragmas(&info, f)
@@ -345,7 +371,7 @@ func (c *compilerContext) parsePragmas(info *functionInfo, f *ssa.Function) {
 				continue
 			}
 			if len(parts) != 2 {
-				c.addError(f.Pos(), fmt.Sprintf("expected one parameter to //go:wasmimport, not %d", len(parts)-1))
+				c.addError(f.Pos(), fmt.Sprintf("expected one parameter to //go:wasmexport, not %d", len(parts)-1))
 				continue
 			}
 			name := parts[1]
@@ -394,14 +420,20 @@ func (c *compilerContext) parsePragmas(info *functionInfo, f *ssa.Function) {
 			if hasUnsafeImport(f.Pkg.Pkg) {
 				info.nobounds = true
 			}
+		case "//go:noescape":
+			// Don't let pointer parameters escape.
+			// Following the upstream Go implementation, we only do this for
+			// declarations, not definitions.
+			if len(f.Blocks) == 0 {
+				info.noescape = true
+			}
 		case "//go:variadic":
 			// The //go:variadic pragma is emitted by the CGo preprocessing
 			// pass for C variadic functions. This includes both explicit
 			// (with ...) and implicit (no parameters in signature)
 			// functions.
-			if strings.HasPrefix(f.Name(), "C.") {
-				// This prefix cannot naturally be created, it must have
-				// been created as a result of CGo preprocessing.
+			if strings.HasPrefix(f.Name(), "_Cgo_") {
+				// This prefix was created as a result of CGo preprocessing.
 				info.variadic = true
 			}
 		}
@@ -206,7 +206,7 @@ entry:
  ret void
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -3,7 +3,7 @@ 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.channelBlockedList = type { ptr, ptr, ptr, { ptr, i32, i32 } }
+%runtime.channelOp = type { ptr, ptr, i32, ptr }
 %runtime.chanSelectState = type { ptr, ptr }

 ; Function Attrs: allockind("alloc,zeroed") allocsize(0)
@@ -18,15 +18,15 @@ entry:
 }

 ; Function Attrs: nounwind
-define hidden void @main.chanIntSend(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #2 {
+define hidden void @main.chanIntSend(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #2 {
 entry:
-  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %chan.op = alloca %runtime.channelOp, align 8
  %chan.value = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %chan.value)
  store i32 3, ptr %chan.value, align 4
-  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %chan.blockedList)
-  call void @runtime.chanSend(ptr %ch, ptr nonnull %chan.value, ptr nonnull %chan.blockedList, ptr undef) #4
-  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %chan.blockedList)
+  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %chan.op)
+  call void @runtime.chanSend(ptr %ch, ptr nonnull %chan.value, ptr nonnull %chan.op, ptr undef) #4
+  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %chan.op)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %chan.value)
  ret void
 }
@@ -34,61 +34,61 @@ entry:
 ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
 declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #3

-declare void @runtime.chanSend(ptr dereferenceable_or_null(32), ptr, ptr dereferenceable_or_null(24), ptr) #1
+declare void @runtime.chanSend(ptr dereferenceable_or_null(36), ptr, ptr dereferenceable_or_null(16), ptr) #1

 ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
 declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #3

 ; Function Attrs: nounwind
-define hidden void @main.chanIntRecv(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #2 {
+define hidden void @main.chanIntRecv(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #2 {
 entry:
-  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
+  %chan.op = alloca %runtime.channelOp, align 8
  %chan.value = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %chan.value)
-  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %chan.blockedList)
-  %0 = call i1 @runtime.chanRecv(ptr %ch, ptr nonnull %chan.value, ptr nonnull %chan.blockedList, ptr undef) #4
+  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %chan.op)
+  %0 = call i1 @runtime.chanRecv(ptr %ch, ptr nonnull %chan.value, ptr nonnull %chan.op, ptr undef) #4
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %chan.value)
-  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %chan.blockedList)
+  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %chan.op)
  ret void
 }

-declare i1 @runtime.chanRecv(ptr dereferenceable_or_null(32), ptr, ptr dereferenceable_or_null(24), ptr) #1
+declare i1 @runtime.chanRecv(ptr dereferenceable_or_null(36), ptr, ptr dereferenceable_or_null(16), ptr) #1

 ; Function Attrs: nounwind
-define hidden void @main.chanZeroSend(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #2 {
+define hidden void @main.chanZeroSend(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #2 {
 entry:
-  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
-  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %chan.blockedList)
-  call void @runtime.chanSend(ptr %ch, ptr null, ptr nonnull %chan.blockedList, ptr undef) #4
-  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %chan.blockedList)
+  %chan.op = alloca %runtime.channelOp, align 8
+  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %chan.op)
+  call void @runtime.chanSend(ptr %ch, ptr null, ptr nonnull %chan.op, ptr undef) #4
+  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %chan.op)
  ret void
 }

 ; Function Attrs: nounwind
-define hidden void @main.chanZeroRecv(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #2 {
+define hidden void @main.chanZeroRecv(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #2 {
 entry:
-  %chan.blockedList = alloca %runtime.channelBlockedList, align 8
-  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %chan.blockedList)
-  %0 = call i1 @runtime.chanRecv(ptr %ch, ptr null, ptr nonnull %chan.blockedList, ptr undef) #4
-  call void @llvm.lifetime.end.p0(i64 24, ptr nonnull %chan.blockedList)
+  %chan.op = alloca %runtime.channelOp, align 8
+  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %chan.op)
+  %0 = call i1 @runtime.chanRecv(ptr %ch, ptr null, ptr nonnull %chan.op, ptr undef) #4
+  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %chan.op)
  ret void
 }

 ; Function Attrs: nounwind
-define hidden void @main.selectZeroRecv(ptr dereferenceable_or_null(32) %ch1, ptr dereferenceable_or_null(32) %ch2, ptr %context) unnamed_addr #2 {
+define hidden void @main.selectZeroRecv(ptr dereferenceable_or_null(36) %ch1, ptr dereferenceable_or_null(36) %ch2, ptr %context) unnamed_addr #2 {
 entry:
  %select.states.alloca = alloca [2 x %runtime.chanSelectState], align 8
  %select.send.value = alloca i32, align 4
  store i32 1, ptr %select.send.value, align 4
  call void @llvm.lifetime.start.p0(i64 16, ptr nonnull %select.states.alloca)
  store ptr %ch1, ptr %select.states.alloca, align 4
-  %select.states.alloca.repack1 = getelementptr inbounds %runtime.chanSelectState, ptr %select.states.alloca, i32 0, i32 1
+  %select.states.alloca.repack1 = getelementptr inbounds i8, ptr %select.states.alloca, i32 4
  store ptr %select.send.value, ptr %select.states.alloca.repack1, align 4
-  %0 = getelementptr inbounds [2 x %runtime.chanSelectState], ptr %select.states.alloca, i32 0, i32 1
+  %0 = getelementptr inbounds i8, ptr %select.states.alloca, i32 8
  store ptr %ch2, ptr %0, align 4
-  %.repack3 = getelementptr inbounds [2 x %runtime.chanSelectState], ptr %select.states.alloca, i32 0, i32 1, i32 1
+  %.repack3 = getelementptr inbounds i8, ptr %select.states.alloca, i32 12
  store ptr null, ptr %.repack3, align 4
-  %select.result = call { i32, i1 } @runtime.tryChanSelect(ptr undef, ptr nonnull %select.states.alloca, i32 2, i32 2, ptr undef) #4
+  %select.result = call { i32, i1 } @runtime.chanSelect(ptr undef, ptr nonnull %select.states.alloca, i32 2, i32 2, ptr null, i32 0, i32 0, ptr undef) #4
  call void @llvm.lifetime.end.p0(i64 16, ptr nonnull %select.states.alloca)
  %1 = extractvalue { i32, i1 } %select.result, 0
  %2 = icmp eq i32 %1, 0
@@ -105,10 +105,10 @@ select.body:                                      ; preds = %select.next
  br label %select.done
 }

-declare { i32, i1 } @runtime.tryChanSelect(ptr, ptr, i32, i32, ptr) #1
+declare { i32, i1 } @runtime.chanSelect(ptr, ptr, i32, i32, ptr, i32, i32, ptr) #1

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
 attributes #4 = { nounwind }
@@ -3,9 +3,8 @@ source_filename = "defer.go"
 target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "thumbv7m-unknown-unknown-eabi"

-%runtime.deferFrame = type { ptr, ptr, [0 x ptr], ptr, i1, %runtime._interface }
+%runtime.deferFrame = type { ptr, ptr, [0 x ptr], ptr, i8, %runtime._interface }
 %runtime._interface = type { ptr, ptr }
-%runtime._defer = type { i32, ptr }

 ; Function Attrs: allockind("alloc,zeroed") allocsize(0)
 declare noalias nonnull ptr @runtime.alloc(i32, ptr, ptr) #0
@@ -28,7 +27,7 @@ entry:
  %0 = call ptr @llvm.stacksave.p0()
  call void @runtime.setupDeferFrame(ptr nonnull %deferframe.buf, ptr %0, ptr undef) #4
  store i32 0, ptr %defer.alloca, align 4
-  %defer.alloca.repack15 = getelementptr inbounds { i32, ptr }, ptr %defer.alloca, i32 0, i32 1
+  %defer.alloca.repack15 = getelementptr inbounds i8, ptr %defer.alloca, i32 4
  store ptr null, ptr %defer.alloca.repack15, align 4
  store ptr %defer.alloca, ptr %deferPtr, align 4
  %setjmp = call i32 asm "\0Amovs r0, #0\0Amov r2, pc\0Astr r2, [r1, #4]", "={r0},{r1},~{r1},~{r2},~{r3},~{r4},~{r5},~{r6},~{r7},~{r8},~{r9},~{r10},~{r11},~{r12},~{lr},~{q0},~{q1},~{q2},~{q3},~{q4},~{q5},~{q6},~{q7},~{q8},~{q9},~{q10},~{q11},~{q12},~{q13},~{q14},~{q15},~{cpsr},~{memory}"(ptr nonnull %deferframe.buf) #5
@@ -52,7 +51,7 @@ rundefers.loophead:                               ; preds = %3, %rundefers.block
  br i1 %stackIsNil, label %rundefers.end, label %rundefers.loop

 rundefers.loop:                                   ; preds = %rundefers.loophead
-  %stack.next.gep = getelementptr inbounds %runtime._defer, ptr %2, i32 0, i32 1
+  %stack.next.gep = getelementptr inbounds i8, ptr %2, i32 4
  %stack.next = load ptr, ptr %stack.next.gep, align 4
  store ptr %stack.next, ptr %deferPtr, align 4
  %callback = load i32, ptr %2, align 4
@@ -88,7 +87,7 @@ rundefers.loophead6:                              ; preds = %5, %lpad
  br i1 %stackIsNil7, label %rundefers.end3, label %rundefers.loop5

 rundefers.loop5:                                  ; preds = %rundefers.loophead6
-  %stack.next.gep8 = getelementptr inbounds %runtime._defer, ptr %4, i32 0, i32 1
+  %stack.next.gep8 = getelementptr inbounds i8, ptr %4, i32 4
  %stack.next9 = load ptr, ptr %stack.next.gep8, align 4
  store ptr %stack.next9, ptr %deferPtr, align 4
  %callback11 = load i32, ptr %4, align 4
@@ -122,12 +121,18 @@ declare void @runtime.destroyDeferFrame(ptr dereferenceable_or_null(24), ptr) #2
 ; Function Attrs: nounwind
 define internal void @"main.deferSimple$1"(ptr %context) unnamed_addr #1 {
 entry:
+  call void @runtime.printlock(ptr undef) #4
  call void @runtime.printint32(i32 3, ptr undef) #4
+  call void @runtime.printunlock(ptr undef) #4
  ret void
 }

+declare void @runtime.printlock(ptr) #2
+
 declare void @runtime.printint32(i32, ptr) #2

+declare void @runtime.printunlock(ptr) #2
+
 ; Function Attrs: nounwind
 define hidden void @main.deferMultiple(ptr %context) unnamed_addr #1 {
 entry:
@@ -139,11 +144,11 @@ entry:
  %0 = call ptr @llvm.stacksave.p0()
  call void @runtime.setupDeferFrame(ptr nonnull %deferframe.buf, ptr %0, ptr undef) #4
  store i32 0, ptr %defer.alloca, align 4
-  %defer.alloca.repack22 = getelementptr inbounds { i32, ptr }, ptr %defer.alloca, i32 0, i32 1
+  %defer.alloca.repack22 = getelementptr inbounds i8, ptr %defer.alloca, i32 4
  store ptr null, ptr %defer.alloca.repack22, align 4
  store ptr %defer.alloca, ptr %deferPtr, align 4
  store i32 1, ptr %defer.alloca2, align 4
-  %defer.alloca2.repack23 = getelementptr inbounds { i32, ptr }, ptr %defer.alloca2, i32 0, i32 1
+  %defer.alloca2.repack23 = getelementptr inbounds i8, ptr %defer.alloca2, i32 4
  store ptr %defer.alloca, ptr %defer.alloca2.repack23, align 4
  store ptr %defer.alloca2, ptr %deferPtr, align 4
  %setjmp = call i32 asm "\0Amovs r0, #0\0Amov r2, pc\0Astr r2, [r1, #4]", "={r0},{r1},~{r1},~{r2},~{r3},~{r4},~{r5},~{r6},~{r7},~{r8},~{r9},~{r10},~{r11},~{r12},~{lr},~{q0},~{q1},~{q2},~{q3},~{q4},~{q5},~{q6},~{q7},~{q8},~{q9},~{q10},~{q11},~{q12},~{q13},~{q14},~{q15},~{cpsr},~{memory}"(ptr nonnull %deferframe.buf) #5
@@ -167,7 +172,7 @@ rundefers.loophead:                               ; preds = %4, %3, %rundefers.b
  br i1 %stackIsNil, label %rundefers.end, label %rundefers.loop

 rundefers.loop:                                   ; preds = %rundefers.loophead
-  %stack.next.gep = getelementptr inbounds %runtime._defer, ptr %2, i32 0, i32 1
+  %stack.next.gep = getelementptr inbounds i8, ptr %2, i32 4
  %stack.next = load ptr, ptr %stack.next.gep, align 4
  store ptr %stack.next, ptr %deferPtr, align 4
  %callback = load i32, ptr %2, align 4
@@ -213,7 +218,7 @@ rundefers.loophead10:                             ; preds = %7, %6, %lpad
  br i1 %stackIsNil11, label %rundefers.end7, label %rundefers.loop9

 rundefers.loop9:                                  ; preds = %rundefers.loophead10
-  %stack.next.gep12 = getelementptr inbounds %runtime._defer, ptr %5, i32 0, i32 1
+  %stack.next.gep12 = getelementptr inbounds i8, ptr %5, i32 4
  %stack.next13 = load ptr, ptr %stack.next.gep12, align 4
  store ptr %stack.next13, ptr %deferPtr, align 4
  %callback15 = load i32, ptr %5, align 4
@@ -250,20 +255,24 @@ rundefers.end7:                                   ; preds = %rundefers.loophead1
 ; Function Attrs: nounwind
 define internal void @"main.deferMultiple$1"(ptr %context) unnamed_addr #1 {
 entry:
+  call void @runtime.printlock(ptr undef) #4
  call void @runtime.printint32(i32 3, ptr undef) #4
+  call void @runtime.printunlock(ptr undef) #4
  ret void
 }

 ; Function Attrs: nounwind
 define internal void @"main.deferMultiple$2"(ptr %context) unnamed_addr #1 {
 entry:
+  call void @runtime.printlock(ptr undef) #4
  call void @runtime.printint32(i32 5, ptr undef) #4
+  call void @runtime.printunlock(ptr undef) #4
  ret void
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
-attributes #1 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
-attributes #2 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #1 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #2 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
 attributes #3 = { nocallback nofree nosync nounwind willreturn }
 attributes #4 = { nounwind }
 attributes #5 = { nounwind returns_twice }
@@ -93,6 +93,6 @@ entry:
  ret i8 %0
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
@@ -44,7 +44,7 @@ entry:
  ret void
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -105,18 +105,18 @@ entry:
  %makeslice = call align 1 dereferenceable(5) ptr @runtime.alloc(i32 5, ptr nonnull inttoptr (i32 3 to ptr), ptr undef) #3
  call void @runtime.trackPointer(ptr nonnull %makeslice, ptr nonnull %stackalloc, ptr undef) #3
  store ptr %makeslice, ptr @main.slice1, align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice1, i32 0, i32 1), align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice1, i32 0, i32 2), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice1, i32 4), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice1, i32 8), align 4
  %makeslice1 = call align 4 dereferenceable(20) ptr @runtime.alloc(i32 20, ptr nonnull inttoptr (i32 67 to ptr), ptr undef) #3
  call void @runtime.trackPointer(ptr nonnull %makeslice1, ptr nonnull %stackalloc, ptr undef) #3
  store ptr %makeslice1, ptr @main.slice2, align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice2, i32 0, i32 1), align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice2, i32 0, i32 2), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice2, i32 4), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice2, i32 8), align 4
  %makeslice3 = call align 4 dereferenceable(60) ptr @runtime.alloc(i32 60, ptr nonnull inttoptr (i32 71 to ptr), ptr undef) #3
  call void @runtime.trackPointer(ptr nonnull %makeslice3, ptr nonnull %stackalloc, ptr undef) #3
  store ptr %makeslice3, ptr @main.slice3, align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice3, i32 0, i32 1), align 4
-  store i32 5, ptr getelementptr inbounds ({ ptr, i32, i32 }, ptr @main.slice3, i32 0, i32 2), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice3, i32 4), align 4
+  store i32 5, ptr getelementptr inbounds (i8, ptr @main.slice3, i32 8), align 4
  ret void
 }

@@ -127,7 +127,7 @@ entry:
  %0 = call align 8 dereferenceable(16) ptr @runtime.alloc(i32 16, ptr null, ptr undef) #3
  call void @runtime.trackPointer(ptr nonnull %0, ptr nonnull %stackalloc, ptr undef) #3
  store double %v.r, ptr %0, align 8
-  %.repack1 = getelementptr inbounds { double, double }, ptr %0, i32 0, i32 1
+  %.repack1 = getelementptr inbounds i8, ptr %0, i32 8
  store double %v.i, ptr %.repack1, align 8
  %1 = insertvalue %runtime._interface { ptr @"reflect/types.type:basic:complex128", ptr undef }, ptr %0, 1
  call void @runtime.trackPointer(ptr nonnull @"reflect/types.type:basic:complex128", ptr nonnull %stackalloc, ptr undef) #3
@@ -135,7 +135,7 @@ entry:
  ret %runtime._interface %1
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -36,7 +36,7 @@ entry:
  br i1 %4, label %unsafe.String.throw, label %unsafe.String.next

 unsafe.String.next:                               ; preds = %entry
-  %5 = zext i16 %len to i32
+  %5 = zext nneg i16 %len to i32
  %6 = insertvalue %runtime._string undef, ptr %ptr, 0
  %7 = insertvalue %runtime._string %6, i32 %5, 1
  call void @runtime.trackPointer(ptr %ptr, ptr nonnull %stackalloc, ptr undef) #3
@@ -57,7 +57,7 @@ entry:
  ret ptr %s.data
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -171,9 +171,9 @@ declare i32 @llvm.smax.i32(i32, i32) #4
 ; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
 declare i32 @llvm.umax.i32(i32, i32) #4

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nocallback nofree nounwind willreturn memory(argmem: write) }
 attributes #4 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
 attributes #5 = { nounwind }
@@ -65,12 +65,14 @@ entry:
  store i32 3, ptr %n, align 4
  %0 = call align 4 dereferenceable(8) ptr @runtime.alloc(i32 8, ptr null, ptr undef) #9
  store i32 5, ptr %0, align 4
-  %1 = getelementptr inbounds { i32, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr %n, ptr %1, align 4
  %stacksize = call i32 @"internal/task.getGoroutineStackSize"(i32 ptrtoint (ptr @"main.closureFunctionGoroutine$1$gowrapper" to i32), ptr undef) #9
  call void @"internal/task.start"(i32 ptrtoint (ptr @"main.closureFunctionGoroutine$1$gowrapper" to i32), ptr nonnull %0, i32 %stacksize, ptr undef) #9
  %2 = load i32, ptr %n, align 4
+  call void @runtime.printlock(ptr undef) #9
  call void @runtime.printint32(i32 %2, ptr undef) #9
+  call void @runtime.printunlock(ptr undef) #9
  ret void
 }

@@ -85,22 +87,26 @@ entry:
 define linkonce_odr void @"main.closureFunctionGoroutine$1$gowrapper"(ptr %0) unnamed_addr #5 {
 entry:
  %1 = load i32, ptr %0, align 4
-  %2 = getelementptr inbounds { i32, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
  call void @"main.closureFunctionGoroutine$1"(i32 %1, ptr %3)
  ret void
 }

+declare void @runtime.printlock(ptr) #2
+
 declare void @runtime.printint32(i32, ptr) #2

+declare void @runtime.printunlock(ptr) #2
+
 ; Function Attrs: nounwind
 define hidden void @main.funcGoroutine(ptr %fn.context, ptr %fn.funcptr, ptr %context) unnamed_addr #1 {
 entry:
  %0 = call align 4 dereferenceable(12) ptr @runtime.alloc(i32 12, ptr null, ptr undef) #9
  store i32 5, ptr %0, align 4
-  %1 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr %fn.context, ptr %1, align 4
-  %2 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 2
+  %2 = getelementptr inbounds i8, ptr %0, i32 8
  store ptr %fn.funcptr, ptr %2, align 4
  %stacksize = call i32 @"internal/task.getGoroutineStackSize"(i32 ptrtoint (ptr @main.funcGoroutine.gowrapper to i32), ptr undef) #9
  call void @"internal/task.start"(i32 ptrtoint (ptr @main.funcGoroutine.gowrapper to i32), ptr nonnull %0, i32 %stacksize, ptr undef) #9
@@ -111,9 +117,9 @@ entry:
 define linkonce_odr void @main.funcGoroutine.gowrapper(ptr %0) unnamed_addr #6 {
 entry:
  %1 = load i32, ptr %0, align 4
-  %2 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
-  %4 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 2
+  %4 = getelementptr inbounds i8, ptr %0, i32 8
  %5 = load ptr, ptr %4, align 4
  call void %5(i32 %1, ptr %3) #9
  ret void
@@ -135,24 +141,24 @@ entry:
 declare i32 @runtime.sliceCopy(ptr nocapture writeonly, ptr nocapture readonly, i32, i32, i32, ptr) #2

 ; Function Attrs: nounwind
-define hidden void @main.closeBuiltinGoroutine(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #1 {
+define hidden void @main.closeBuiltinGoroutine(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #1 {
 entry:
  call void @runtime.chanClose(ptr %ch, ptr undef) #9
  ret void
 }

-declare void @runtime.chanClose(ptr dereferenceable_or_null(32), ptr) #2
+declare void @runtime.chanClose(ptr dereferenceable_or_null(36), ptr) #2

 ; Function Attrs: nounwind
 define hidden void @main.startInterfaceMethod(ptr %itf.typecode, ptr %itf.value, ptr %context) unnamed_addr #1 {
 entry:
  %0 = call align 4 dereferenceable(16) ptr @runtime.alloc(i32 16, ptr null, ptr undef) #9
  store ptr %itf.value, ptr %0, align 4
-  %1 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr @"main$string", ptr %1, align 4
-  %2 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 2
+  %2 = getelementptr inbounds i8, ptr %0, i32 8
  store i32 4, ptr %2, align 4
-  %3 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 3
+  %3 = getelementptr inbounds i8, ptr %0, i32 12
  store ptr %itf.typecode, ptr %3, align 4
  %stacksize = call i32 @"internal/task.getGoroutineStackSize"(i32 ptrtoint (ptr @"interface:{Print:func:{basic:string}{}}.Print$invoke$gowrapper" to i32), ptr undef) #9
  call void @"internal/task.start"(i32 ptrtoint (ptr @"interface:{Print:func:{basic:string}{}}.Print$invoke$gowrapper" to i32), ptr nonnull %0, i32 %stacksize, ptr undef) #9
@@ -165,23 +171,23 @@ declare void @"interface:{Print:func:{basic:string}{}}.Print$invoke"(ptr, ptr, i
 define linkonce_odr void @"interface:{Print:func:{basic:string}{}}.Print$invoke$gowrapper"(ptr %0) unnamed_addr #8 {
 entry:
  %1 = load ptr, ptr %0, align 4
-  %2 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
-  %4 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 2
+  %4 = getelementptr inbounds i8, ptr %0, i32 8
  %5 = load i32, ptr %4, align 4
-  %6 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 3
+  %6 = getelementptr inbounds i8, ptr %0, i32 12
  %7 = load ptr, ptr %6, align 4
  call void @"interface:{Print:func:{basic:string}{}}.Print$invoke"(ptr %1, ptr %3, i32 %5, ptr %7, ptr undef) #9
  ret void
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
-attributes #1 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
-attributes #2 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
-attributes #3 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.regularFunction" }
-attributes #4 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.inlineFunctionGoroutine$1" }
-attributes #5 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.closureFunctionGoroutine$1" }
-attributes #6 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper" }
-attributes #7 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-invoke"="reflect/methods.Print(string)" "tinygo-methods"="reflect/methods.Print(string)" }
-attributes #8 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="interface:{Print:func:{basic:string}{}}.Print$invoke" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #1 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #2 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" }
+attributes #3 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.regularFunction" }
+attributes #4 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.inlineFunctionGoroutine$1" }
+attributes #5 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="main.closureFunctionGoroutine$1" }
+attributes #6 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper" }
+attributes #7 = { "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-invoke"="reflect/methods.Print(string)" "tinygo-methods"="reflect/methods.Print(string)" }
+attributes #8 = { nounwind "target-features"="+armv7-m,+hwdiv,+soft-float,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-pacbti,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "tinygo-gowrapper"="interface:{Print:func:{basic:string}{}}.Print$invoke" }
 attributes #9 = { nounwind }
@@ -72,11 +72,13 @@ entry:
  %0 = call align 4 dereferenceable(8) ptr @runtime.alloc(i32 8, ptr null, ptr undef) #9
  call void @runtime.trackPointer(ptr nonnull %0, ptr nonnull %stackalloc, ptr undef) #9
  store i32 5, ptr %0, align 4
-  %1 = getelementptr inbounds { i32, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr %n, ptr %1, align 4
  call void @"internal/task.start"(i32 ptrtoint (ptr @"main.closureFunctionGoroutine$1$gowrapper" to i32), ptr nonnull %0, i32 65536, ptr undef) #9
  %2 = load i32, ptr %n, align 4
+  call void @runtime.printlock(ptr undef) #9
  call void @runtime.printint32(i32 %2, ptr undef) #9
+  call void @runtime.printunlock(ptr undef) #9
  ret void
 }

@@ -91,15 +93,19 @@ entry:
 define linkonce_odr void @"main.closureFunctionGoroutine$1$gowrapper"(ptr %0) unnamed_addr #5 {
 entry:
  %1 = load i32, ptr %0, align 4
-  %2 = getelementptr inbounds { i32, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
  call void @"main.closureFunctionGoroutine$1"(i32 %1, ptr %3)
  call void @runtime.deadlock(ptr undef) #9
  unreachable
 }

+declare void @runtime.printlock(ptr) #1
+
 declare void @runtime.printint32(i32, ptr) #1

+declare void @runtime.printunlock(ptr) #1
+
 ; Function Attrs: nounwind
 define hidden void @main.funcGoroutine(ptr %fn.context, ptr %fn.funcptr, ptr %context) unnamed_addr #2 {
 entry:
@@ -107,9 +113,9 @@ entry:
  %0 = call align 4 dereferenceable(12) ptr @runtime.alloc(i32 12, ptr null, ptr undef) #9
  call void @runtime.trackPointer(ptr nonnull %0, ptr nonnull %stackalloc, ptr undef) #9
  store i32 5, ptr %0, align 4
-  %1 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr %fn.context, ptr %1, align 4
-  %2 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 2
+  %2 = getelementptr inbounds i8, ptr %0, i32 8
  store ptr %fn.funcptr, ptr %2, align 4
  call void @"internal/task.start"(i32 ptrtoint (ptr @main.funcGoroutine.gowrapper to i32), ptr nonnull %0, i32 65536, ptr undef) #9
  ret void
@@ -119,9 +125,9 @@ entry:
 define linkonce_odr void @main.funcGoroutine.gowrapper(ptr %0) unnamed_addr #6 {
 entry:
  %1 = load i32, ptr %0, align 4
-  %2 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
-  %4 = getelementptr inbounds { i32, ptr, ptr }, ptr %0, i32 0, i32 2
+  %4 = getelementptr inbounds i8, ptr %0, i32 8
  %5 = load ptr, ptr %4, align 4
  call void %5(i32 %1, ptr %3) #9
  call void @runtime.deadlock(ptr undef) #9
@@ -144,13 +150,13 @@ entry:
 declare i32 @runtime.sliceCopy(ptr nocapture writeonly, ptr nocapture readonly, i32, i32, i32, ptr) #1

 ; Function Attrs: nounwind
-define hidden void @main.closeBuiltinGoroutine(ptr dereferenceable_or_null(32) %ch, ptr %context) unnamed_addr #2 {
+define hidden void @main.closeBuiltinGoroutine(ptr dereferenceable_or_null(36) %ch, ptr %context) unnamed_addr #2 {
 entry:
  call void @runtime.chanClose(ptr %ch, ptr undef) #9
  ret void
 }

-declare void @runtime.chanClose(ptr dereferenceable_or_null(32), ptr) #1
+declare void @runtime.chanClose(ptr dereferenceable_or_null(36), ptr) #1

 ; Function Attrs: nounwind
 define hidden void @main.startInterfaceMethod(ptr %itf.typecode, ptr %itf.value, ptr %context) unnamed_addr #2 {
@@ -159,11 +165,11 @@ entry:
  %0 = call align 4 dereferenceable(16) ptr @runtime.alloc(i32 16, ptr null, ptr undef) #9
  call void @runtime.trackPointer(ptr nonnull %0, ptr nonnull %stackalloc, ptr undef) #9
  store ptr %itf.value, ptr %0, align 4
-  %1 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 1
+  %1 = getelementptr inbounds i8, ptr %0, i32 4
  store ptr @"main$string", ptr %1, align 4
-  %2 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 2
+  %2 = getelementptr inbounds i8, ptr %0, i32 8
  store i32 4, ptr %2, align 4
-  %3 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 3
+  %3 = getelementptr inbounds i8, ptr %0, i32 12
  store ptr %itf.typecode, ptr %3, align 4
  call void @"internal/task.start"(i32 ptrtoint (ptr @"interface:{Print:func:{basic:string}{}}.Print$invoke$gowrapper" to i32), ptr nonnull %0, i32 65536, ptr undef) #9
  ret void
@@ -175,24 +181,24 @@ declare void @"interface:{Print:func:{basic:string}{}}.Print$invoke"(ptr, ptr, i
 define linkonce_odr void @"interface:{Print:func:{basic:string}{}}.Print$invoke$gowrapper"(ptr %0) unnamed_addr #8 {
 entry:
  %1 = load ptr, ptr %0, align 4
-  %2 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 1
+  %2 = getelementptr inbounds i8, ptr %0, i32 4
  %3 = load ptr, ptr %2, align 4
-  %4 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 2
+  %4 = getelementptr inbounds i8, ptr %0, i32 8
  %5 = load i32, ptr %4, align 4
-  %6 = getelementptr inbounds { ptr, ptr, i32, ptr }, ptr %0, i32 0, i32 3
+  %6 = getelementptr inbounds i8, ptr %0, i32 12
  %7 = load ptr, ptr %6, align 4
  call void @"interface:{Print:func:{basic:string}{}}.Print$invoke"(ptr %1, ptr %3, i32 %5, ptr %7, ptr undef) #9
  call void @runtime.deadlock(ptr undef) #9
  unreachable
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #3 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-gowrapper"="main.regularFunction" }
-attributes #4 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-gowrapper"="main.inlineFunctionGoroutine$1" }
-attributes #5 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-gowrapper"="main.closureFunctionGoroutine$1" }
-attributes #6 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-gowrapper" }
-attributes #7 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-invoke"="reflect/methods.Print(string)" "tinygo-methods"="reflect/methods.Print(string)" }
-attributes #8 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-gowrapper"="interface:{Print:func:{basic:string}{}}.Print$invoke" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #3 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-gowrapper"="main.regularFunction" }
+attributes #4 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-gowrapper"="main.inlineFunctionGoroutine$1" }
+attributes #5 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-gowrapper"="main.closureFunctionGoroutine$1" }
+attributes #6 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-gowrapper" }
+attributes #7 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-invoke"="reflect/methods.Print(string)" "tinygo-methods"="reflect/methods.Print(string)" }
+attributes #8 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-gowrapper"="interface:{Print:func:{basic:string}{}}.Print$invoke" }
 attributes #9 = { nounwind }
@@ -130,11 +130,11 @@ entry:

 declare %runtime._string @"interface:{Error:func:{}{basic:string}}.Error$invoke"(ptr, ptr, ptr) #6

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #3 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-methods"="reflect/methods.Error() string" }
-attributes #4 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-methods"="reflect/methods.String() string" }
-attributes #5 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-invoke"="main.$methods.foo(int) uint8" "tinygo-methods"="reflect/methods.String() string; main.$methods.foo(int) uint8" }
-attributes #6 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "tinygo-invoke"="reflect/methods.Error() string" "tinygo-methods"="reflect/methods.Error() string" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #3 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-methods"="reflect/methods.Error() string" }
+attributes #4 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-methods"="reflect/methods.String() string" }
+attributes #5 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-invoke"="main.$methods.foo(int) uint8" "tinygo-methods"="reflect/methods.String() string; main.$methods.foo(int) uint8" }
+attributes #6 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "tinygo-invoke"="reflect/methods.Error() string" "tinygo-methods"="reflect/methods.Error() string" }
 attributes #7 = { nounwind }
@@ -44,7 +44,7 @@ entry:
  ret ptr %x
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -106,3 +106,12 @@ var undefinedGlobalNotInSection uint32
 //go:align 1024
 //go:section .global_section
 var multipleGlobalPragmas uint32
+
+//go:noescape
+func doesNotEscapeParam(a *int, b []int, c chan int, d *[0]byte)
+
+// The //go:noescape pragma only works on declarations, not definitions.
+//
+//go:noescape
+func stillEscapes(a *int, b []int, c chan int, d *[0]byte) {
+}
@@ -85,13 +85,21 @@ entry:

 declare void @main.undefinedFunctionNotInSection(ptr) #1

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #3 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="extern_func" }
-attributes #4 = { inlinehint nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #5 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #6 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="exportedFunctionInSection" }
-attributes #7 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "wasm-import-module"="modulename" "wasm-import-name"="import1" }
-attributes #8 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "wasm-import-module"="foobar" "wasm-import-name"="imported" }
-attributes #9 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" "wasm-export-name"="exported" }
+declare void @main.doesNotEscapeParam(ptr nocapture dereferenceable_or_null(4), ptr nocapture, i32, i32, ptr nocapture dereferenceable_or_null(36), ptr nocapture, ptr) #1
+
+; Function Attrs: nounwind
+define hidden void @main.stillEscapes(ptr dereferenceable_or_null(4) %a, ptr %b.data, i32 %b.len, i32 %b.cap, ptr dereferenceable_or_null(36) %c, ptr %d, ptr %context) unnamed_addr #2 {
+entry:
+  ret void
+}
+
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #3 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "wasm-export-name"="extern_func" }
+attributes #4 = { inlinehint nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #5 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #6 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "wasm-export-name"="exportedFunctionInSection" }
+attributes #7 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "wasm-import-module"="modulename" "wasm-import-name"="import1" }
+attributes #8 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "wasm-import-module"="foobar" "wasm-import-name"="imported" }
+attributes #9 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" "wasm-export-name"="exported" }
@@ -51,9 +51,9 @@ entry:
  %varargs = call align 4 dereferenceable(12) ptr @runtime.alloc(i32 12, ptr nonnull inttoptr (i32 3 to ptr), ptr undef) #3
  call void @runtime.trackPointer(ptr nonnull %varargs, ptr nonnull %stackalloc, ptr undef) #3
  store i32 1, ptr %varargs, align 4
-  %0 = getelementptr inbounds [3 x i32], ptr %varargs, i32 0, i32 1
+  %0 = getelementptr inbounds i8, ptr %varargs, i32 4
  store i32 2, ptr %0, align 4
-  %1 = getelementptr inbounds [3 x i32], ptr %varargs, i32 0, i32 2
+  %1 = getelementptr inbounds i8, ptr %varargs, i32 8
  store i32 3, ptr %1, align 4
  %append.new = call { ptr, i32, i32 } @runtime.sliceAppend(ptr %ints.data, ptr nonnull %varargs, i32 %ints.len, i32 %ints.cap, i32 3, i32 4, ptr undef) #3
  %append.newPtr = extractvalue { ptr, i32, i32 } %append.new, 0
@@ -286,7 +286,7 @@ entry:
  br i1 %4, label %unsafe.Slice.throw, label %unsafe.Slice.next

 unsafe.Slice.next:                                ; preds = %entry
-  %5 = trunc i64 %len to i32
+  %5 = trunc nuw i64 %len to i32
  %6 = insertvalue { ptr, i32, i32 } undef, ptr %ptr, 0
  %7 = insertvalue { ptr, i32, i32 } %6, i32 %5, 1
  %8 = insertvalue { ptr, i32, i32 } %7, i32 %5, 2
@@ -310,7 +310,7 @@ entry:
  br i1 %4, label %unsafe.Slice.throw, label %unsafe.Slice.next

 unsafe.Slice.next:                                ; preds = %entry
-  %5 = trunc i64 %len to i32
+  %5 = trunc nuw i64 %len to i32
  %6 = insertvalue { ptr, i32, i32 } undef, ptr %ptr, 0
  %7 = insertvalue { ptr, i32, i32 } %6, i32 %5, 1
  %8 = insertvalue { ptr, i32, i32 } %7, i32 %5, 2
@@ -322,7 +322,7 @@ unsafe.Slice.throw:                               ; preds = %entry
  unreachable
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -97,7 +97,7 @@ lookup.throw:                                     ; preds = %entry
  unreachable
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #3 = { nounwind }
@@ -81,7 +81,7 @@ entry:
  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %hashmap.key)
  %s.elt = extractvalue [2 x %main.hasPadding] %s, 0
  store %main.hasPadding %s.elt, ptr %hashmap.key, align 4
-  %hashmap.key.repack1 = getelementptr inbounds [2 x %main.hasPadding], ptr %hashmap.key, i32 0, i32 1
+  %hashmap.key.repack1 = getelementptr inbounds i8, ptr %hashmap.key, i32 12
  %s.elt2 = extractvalue [2 x %main.hasPadding] %s, 1
  store %main.hasPadding %s.elt2, ptr %hashmap.key.repack1, align 4
  %0 = getelementptr inbounds i8, ptr %hashmap.key, i32 1
@@ -109,7 +109,7 @@ entry:
  call void @llvm.lifetime.start.p0(i64 24, ptr nonnull %hashmap.key)
  %s.elt = extractvalue [2 x %main.hasPadding] %s, 0
  store %main.hasPadding %s.elt, ptr %hashmap.key, align 4
-  %hashmap.key.repack1 = getelementptr inbounds [2 x %main.hasPadding], ptr %hashmap.key, i32 0, i32 1
+  %hashmap.key.repack1 = getelementptr inbounds i8, ptr %hashmap.key, i32 12
  %s.elt2 = extractvalue [2 x %main.hasPadding] %s, 1
  store %main.hasPadding %s.elt2, ptr %hashmap.key.repack1, align 4
  %0 = getelementptr inbounds i8, ptr %hashmap.key, i32 1
@@ -132,9 +132,9 @@ entry:
  ret void
 }

-attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
-attributes #3 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext" }
+attributes #0 = { allockind("alloc,zeroed") allocsize(0) "alloc-family"="runtime.alloc" "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #1 = { "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #2 = { nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
+attributes #3 = { noinline nounwind "target-features"="+bulk-memory,+mutable-globals,+nontrapping-fptoint,+sign-ext,-multivalue,-reference-types" }
 attributes #4 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
 attributes #5 = { nounwind }
@@ -3,7 +3,7 @@ module github.com/tinygo-org/tinygo
 go 1.19

 require (
-	github.com/aykevl/go-wasm v0.0.2-0.20240312204833-50275154210c
+	github.com/aykevl/go-wasm v0.0.2-0.20240825160117-b76c3f9f0982
 	github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2
 	github.com/chromedp/cdproto v0.0.0-20220113222801-0725d94bb6ee
 	github.com/chromedp/chromedp v0.7.6
@@ -20,7 +20,7 @@ require (
 	golang.org/x/sys v0.21.0
 	golang.org/x/tools v0.22.1-0.20240621165957-db513b091504
 	gopkg.in/yaml.v2 v2.4.0
-	tinygo.org/x/go-llvm v0.0.0-20240627184919-3b50c76783a8
+	tinygo.org/x/go-llvm v0.0.0-20250119132755-9dca92dfb4f9
 )

 require (
@@ -1,5 +1,5 @@
-github.com/aykevl/go-wasm v0.0.2-0.20240312204833-50275154210c h1:4T0Vj1UkGgcpkRrmn7SbokebnlfxJcMZPgWtOYACAAA=
-github.com/aykevl/go-wasm v0.0.2-0.20240312204833-50275154210c/go.mod h1:7sXyiaA0WtSogCu67R2252fQpVmJMh9JWJ9ddtGkpWw=
+github.com/aykevl/go-wasm v0.0.2-0.20240825160117-b76c3f9f0982 h1:cD7QfvrJdYmBw2tFP/VyKPT8ZESlcrwSwo7SvH9Y4dc=
+github.com/aykevl/go-wasm v0.0.2-0.20240825160117-b76c3f9f0982/go.mod h1:7sXyiaA0WtSogCu67R2252fQpVmJMh9JWJ9ddtGkpWw=
 github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2 h1:oMCHnXa6CCCafdPDbMh/lWRhRByN0VFLvv+g+ayx1SI=
 github.com/blakesmith/ar v0.0.0-20150311145944-8bd4349a67f2/go.mod h1:PkYb9DJNAwrSvRx5DYA+gUcOIgTGVMNkfSCbZM8cWpI=
 github.com/chromedp/cdproto v0.0.0-20211126220118-81fa0469ad77/go.mod h1:At5TxYYdxkbQL0TSefRjhLE3Q0lgvqKKMSFUglJ7i1U=
@@ -74,5 +74,5 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
-tinygo.org/x/go-llvm v0.0.0-20240627184919-3b50c76783a8 h1:bLsZXRUBavt++CJlMN7sppNziqu3LyamESLhFJcpqFQ=
-tinygo.org/x/go-llvm v0.0.0-20240627184919-3b50c76783a8/go.mod h1:GFbusT2VTA4I+l4j80b17KFK+6whv69Wtny5U+T8RR0=
+tinygo.org/x/go-llvm v0.0.0-20250119132755-9dca92dfb4f9 h1:rMvEzuCYjyiR+pmdiCVWTQw3L6VqiSIXoL19I3lYufE=
+tinygo.org/x/go-llvm v0.0.0-20250119132755-9dca92dfb4f9/go.mod h1:GFbusT2VTA4I+l4j80b17KFK+6whv69Wtny5U+T8RR0=
@@ -10,7 +10,7 @@ import (

 // Version of TinyGo.
 // Update this value before release of new version of software.
-const version = "0.35.0-dev"
+const version = "0.36.0"

 // Return TinyGo version, either in the form 0.30.0 or as a development version
 // (like 0.30.0-dev-abcd012).
@@ -287,9 +287,17 @@ func (r *runner) run(fn *function, params []value, parentMem *memoryView, indent
 				// Get the object layout, if it is available.
 				llvmLayoutType := r.getLLVMTypeFromLayout(operands[2])

+				// Get the alignment of the memory to be allocated.
+				alignment := 0 // use default alignment if unset
+				alignAttr := inst.llvmInst.GetCallSiteEnumAttribute(0, llvm.AttributeKindID("align"))
+				if !alignAttr.IsNil() {
+					alignment = int(alignAttr.GetEnumValue())
+				}
+
 				// Create the object.
 				alloc := object{
 					globalName:     r.pkgName + "$alloc",
+					align:          alignment,
 					llvmLayoutType: llvmLayoutType,
 					buffer:         newRawValue(uint32(size)),
 					size:           uint32(size),
@@ -646,6 +654,7 @@ func (r *runner) run(fn *function, params []value, parentMem *memoryView, indent
 				globalName: r.pkgName + "$alloca",
 				buffer:     newRawValue(uint32(size)),
 				size:       uint32(size),
+				align:      inst.llvmInst.Alignment(),
 			}
 			index := len(r.objects)
 			r.objects = append(r.objects, alloca)
@@ -961,9 +970,9 @@ func (r *runner) runAtRuntime(fn *function, inst instruction, locals []value, me
 	case llvm.Call:
 		llvmFn := operands[len(operands)-1]
 		args := operands[:len(operands)-1]
-		for _, arg := range args {
-			if arg.Type().TypeKind() == llvm.PointerTypeKind {
-				err := mem.markExternalStore(arg)
+		for _, op := range operands {
+			if op.Type().TypeKind() == llvm.PointerTypeKind {
+				err := mem.markExternalStore(op)
 				if err != nil {
 					return r.errorAt(inst, err)
 				}
@@ -42,6 +42,7 @@ type object struct {
 	globalName     string    // name, if not yet created (not guaranteed to be the final name)
 	buffer         value     // buffer with value as given by interp, nil if external
 	size           uint32    // must match buffer.len(), if available
+	align          int       // alignment of the object (may be 0 if unknown)
 	constant       bool      // true if this is a constant global
 	marked         uint8     // 0 means unmarked, 1 means external read, 2 means external write
 }
@@ -593,6 +594,12 @@ func (v pointerValue) toLLVMValue(llvmType llvm.Type, mem *memoryView) (llvm.Val
 		// runtime.alloc.
 		// First allocate a new global for this object.
 		obj := mem.get(v.index())
+		alignment := obj.align
+		if alignment == 0 {
+			// Unknown alignment, perhaps from a direct call to runtime.alloc in
+			// the runtime. Use a conservative default instead.
+			alignment = mem.r.maxAlign
+		}
 		if obj.llvmType.IsNil() && obj.llvmLayoutType.IsNil() {
 			// Create an initializer without knowing the global type.
 			// This is probably the result of a runtime.alloc call.
@@ -603,7 +610,7 @@ func (v pointerValue) toLLVMValue(llvmType llvm.Type, mem *memoryView) (llvm.Val
 			globalType := initializer.Type()
 			llvmValue = llvm.AddGlobal(mem.r.mod, globalType, obj.globalName)
 			llvmValue.SetInitializer(initializer)
-			llvmValue.SetAlignment(mem.r.maxAlign)
+			llvmValue.SetAlignment(alignment)
 			obj.llvmGlobal = llvmValue
 			mem.put(v.index(), obj)
 		} else {
@@ -642,11 +649,7 @@ func (v pointerValue) toLLVMValue(llvmType llvm.Type, mem *memoryView) (llvm.Val
 				return llvm.Value{}, errors.New("interp: allocated value does not match allocated type")
 			}
 			llvmValue.SetInitializer(initializer)
-			if obj.llvmType.IsNil() {
-				// The exact type isn't known (only the layout), so use the
-				// alignment that would normally be expected from runtime.alloc.
-				llvmValue.SetAlignment(mem.r.maxAlign)
-			}
+			llvmValue.SetAlignment(alignment)
 		}

 		// It should be included in r.globals because otherwise markExternal
@@ -1043,6 +1046,8 @@ func (v *rawValue) set(llvmValue llvm.Value, r *runner) {
 				v.buf[i] = ptrValue.pointer
 			}
 		case llvm.ICmp:
+			// Note: constant icmp isn't supported anymore in LLVM 19.
+			// Once we drop support for LLVM 18, this can be removed.
 			size := r.targetData.TypeAllocSize(llvmValue.Operand(0).Type())
 			lhs := newRawValue(uint32(size))
 			rhs := newRawValue(uint32(size))
@@ -3,7 +3,6 @@ target triple = "x86_64--linux"

@intToPtrResult = global i8 0
@ptrToIntResult = global i8 0
-@icmpResult = global i8 0
@pointerTagResult = global i64 0
@someArray = internal global {i16, i8, i8} zeroinitializer
@someArrayPointer = global ptr zeroinitializer
@@ -17,7 +16,6 @@ define internal void @main.init() {
  call void @testIntToPtr()
  call void @testPtrToInt()
  call void @testConstGEP()
-  call void @testICmp()
  call void @testPointerTag()
  ret void
 }
@@ -53,19 +51,6 @@ define internal void @testConstGEP() {
  ret void
 }

-define internal void @testICmp() {
-  br i1 icmp eq (i64 ptrtoint (ptr @ptrToIntResult to i64), i64 0), label %equal, label %unequal
-equal:
-  ; should not be reached
-  store i8 1, ptr @icmpResult
-  ret void
-unequal:
-  ; should be reached
-  store i8 2, ptr @icmpResult
-  ret void
-  ret void
-}
-
 define internal void @testPointerTag() {
  %val = and i64 ptrtoint (ptr getelementptr inbounds (i8, ptr @someArray, i32 2) to i64), 3
  store i64 %val, ptr @pointerTagResult
@@ -3,10 +3,9 @@ target triple = "x86_64--linux"

@intToPtrResult = local_unnamed_addr global i8 2
@ptrToIntResult = local_unnamed_addr global i8 2
-@icmpResult = local_unnamed_addr global i8 2
@pointerTagResult = local_unnamed_addr global i64 2
@someArray = internal global { i16, i8, i8 } zeroinitializer
-@someArrayPointer = local_unnamed_addr global ptr getelementptr inbounds ({ i16, i8, i8 }, ptr @someArray, i64 0, i32 1)
+@someArrayPointer = local_unnamed_addr global ptr getelementptr inbounds (i8, ptr @someArray, i64 2)

 define void @runtime.initAll() local_unnamed_addr {
  ret void
@@ -243,6 +243,7 @@ func pathsToOverride(goMinor int, needsSyscallPackage bool) map[string]bool {
 		"internal/binary/":            false,
 		"internal/bytealg/":           false,
 		"internal/cm/":                false,
+		"internal/futex/":             false,
 		"internal/fuzz/":              false,
 		"internal/reflectlite/":       false,
 		"internal/gclayout":           false,
@@ -268,6 +269,8 @@ func pathsToOverride(goMinor int, needsSyscallPackage bool) map[string]bool {

 	if needsSyscallPackage {
 		paths["syscall/"] = true // include syscall/js
+		paths["internal/syscall/"] = true
+		paths["internal/syscall/unix/"] = false
 	}
 	return paths
 }
@@ -485,7 +485,7 @@ func (p *Package) parseFiles() ([]*ast.File, error) {
 		var initialCFlags []string
 		initialCFlags = append(initialCFlags, p.program.config.CFlags(true)...)
 		initialCFlags = append(initialCFlags, "-I"+p.Dir)
-		generated, headerCode, cflags, ldflags, accessedFiles, errs := cgo.Process(files, p.program.workingDir, p.ImportPath, p.program.fset, initialCFlags)
+		generated, headerCode, cflags, ldflags, accessedFiles, errs := cgo.Process(files, p.program.workingDir, p.ImportPath, p.program.fset, initialCFlags, p.program.config.GOOS())
 		p.CFlags = append(initialCFlags, cflags...)
 		p.CGoHeaders = headerCode
 		for path, hash := range accessedFiles {
@@ -1062,9 +1062,8 @@ func findFATMounts(options *compileopts.Options) ([]mountPoint, error) {
 		return points, nil
 	case "windows":
 		// Obtain a list of all currently mounted volumes.
-		cmd := executeCommand(options, "wmic",
-			"PATH", "Win32_LogicalDisk",
-			"get", "DeviceID,VolumeName,FileSystem,DriveType")
+		cmd := executeCommand(options, "powershell", "-c",
+			"Get-CimInstance -ClassName Win32_LogicalDisk | Select-Object DeviceID, DriveType, FileSystem, VolumeName")
 		var out bytes.Buffer
 		cmd.Stdout = &out
 		err := cmd.Run()
@@ -1502,14 +1501,14 @@ func main() {
 	var tags buildutil.TagsFlag
 	flag.Var(&tags, "tags", "a space-separated list of extra build tags")
 	target := flag.String("target", "", "chip/board name or JSON target specification file")
-	buildMode := flag.String("buildmode", "", "build mode to use (default, c-shared)")
+	buildMode := flag.String("buildmode", "", "build mode to use (default, c-shared, wasi-legacy)")
 	var stackSize uint64
 	flag.Func("stack-size", "goroutine stack size (if unknown at compile time)", func(s string) error {
 		size, err := bytesize.Parse(s)
 		stackSize = uint64(size)
 		return err
 	})
-	printSize := flag.String("size", "", "print sizes (none, short, full)")
+	printSize := flag.String("size", "", "print sizes (none, short, full, html)")
 	printStacks := flag.Bool("print-stacks", false, "print stack sizes of goroutines")
 	printAllocsString := flag.String("print-allocs", "", "regular expression of functions for which heap allocations should be printed")
 	printCommands := flag.Bool("x", false, "Print commands")
@@ -1685,8 +1684,24 @@ func main() {
 			usage(command)
 			os.Exit(1)
 		}
-		if options.Target == "" && filepath.Ext(outpath) == ".wasm" {
-			options.Target = "wasm"
+		if options.Target == "" {
+			switch {
+			case options.GOARCH == "wasm":
+				switch options.GOOS {
+				case "js":
+					options.Target = "wasm"
+				case "wasip1":
+					options.Target = "wasip1"
+				case "wasip2":
+					options.Target = "wasip2"
+				default:
+					fmt.Fprintln(os.Stderr, "GOARCH=wasm but GOOS is not set correctly. Please set GOOS to wasm, wasip1, or wasip2.")
+					os.Exit(1)
+				}
+			case filepath.Ext(outpath) == ".wasm":
+				fmt.Fprintln(os.Stderr, "you appear to want to build a wasm file, but have not specified either a target flag, or the GOARCH/GOOS to use.")
+				os.Exit(1)
+			}
 		}

 		err := Build(pkgName, outpath, options)
@@ -7,7 +7,6 @@ import (
 	"bufio"
 	"bytes"
 	"context"
-	"crypto/sha256"
 	"errors"
 	"flag"
 	"io"
@@ -16,7 +15,6 @@ import (
 	"reflect"
 	"regexp"
 	"runtime"
-	"strconv"
 	"strings"
 	"sync"
 	"testing"
@@ -29,6 +27,7 @@ import (
 	"github.com/tetratelabs/wazero/sys"
 	"github.com/tinygo-org/tinygo/builder"
 	"github.com/tinygo-org/tinygo/compileopts"
+	"github.com/tinygo-org/tinygo/diagnostics"
 	"github.com/tinygo-org/tinygo/goenv"
 )

@@ -115,15 +114,10 @@ func TestBuild(t *testing.T) {
 		return
 	}

-	t.Run("Debugging", func(t *testing.T) {
-		for i := 0; i < 5; i++ {
-			t.Run(strconv.Itoa(i), func(t *testing.T) {
-				options := optionsFromTarget("", sema)
-				runTest("alias.go", options, t, nil, nil)
-			})
-		}
+	t.Run("Host", func(t *testing.T) {
+		t.Parallel()
+		runPlatTests(optionsFromTarget("", sema), tests, t)
 	})
-	return

 	// Test a few build options.
 	t.Run("build-options", func(t *testing.T) {
@@ -426,67 +420,22 @@ func runTestWithConfig(name string, t *testing.T, options compileopts.Options, c

 	// Build the test binary.
 	stdout := &bytes.Buffer{}
-	_, fileExt := config.EmulatorFormat()
-	tmpdir := t.TempDir()
-	result, err := builder.Build(pkgName, fileExt, tmpdir, config)
+	_, err = buildAndRun(pkgName, config, stdout, cmdArgs, environmentVars, time.Minute, func(cmd *exec.Cmd, result builder.BuildResult) error {
+		return cmd.Run()
+	})
 	if err != nil {
-		t.Fatal("build failed:", err)
+		w := &bytes.Buffer{}
+		diagnostics.CreateDiagnostics(err).WriteTo(w, "")
+		for _, line := range strings.Split(strings.TrimRight(w.String(), "\n"), "\n") {
+			t.Log(line)
+		}
+		if stdout.Len() != 0 {
+			t.Logf("output:\n%s", stdout.String())
+		}
+		t.Fail()
+		return
 	}

-	data, err := os.ReadFile(result.Executable)
-	if err != nil {
-		t.Fatal("failed to read executable:", err)
-	}
-	hash := sha256.Sum256(data)
-	t.Logf("executable hash and size: %d %x", len(data), hash)
-
-	for i := 0; i < 100; i++ {
-		i := i
-		t.Run(strconv.Itoa(i), func(t *testing.T) {
-			t.Parallel()
-			stdout := &bytes.Buffer{}
-			cmd := exec.Command(result.Executable)
-			cmd.Stdout = stdout
-			cmd.Stderr = stdout
-			err := cmd.Run()
-			if err != nil {
-				t.Log("run error:", err)
-			}
-			checkOutput(t, expectedOutputPath, stdout.Bytes())
-		})
-	}
-	return
-
-	//_, err = buildAndRun(pkgName, config, stdout, cmdArgs, environmentVars, time.Minute, func(cmd *exec.Cmd, result builder.BuildResult) error {
-	//	data, err := os.ReadFile(result.Executable)
-	//	if err != nil {
-	//		t.Fatal("failed to read executable:", err)
-	//	}
-	//	hash := sha256.Sum256(data)
-	//	t.Logf("executable hash and size: %d %x", len(data), hash)
-
-	//	t.Log("command:", cmd)
-	//	err = cmd.Run()
-	//	if err == nil {
-	//		t.Log("  error is nil!")
-	//	} else {
-	//		t.Log("  error:", err)
-	//	}
-	//	return err
-	//})
-	//if err != nil {
-	//	w := &bytes.Buffer{}
-	//	diagnostics.CreateDiagnostics(err).WriteTo(w, "")
-	//	for _, line := range strings.Split(strings.TrimRight(w.String(), "\n"), "\n") {
-	//		t.Log(line)
-	//	}
-	//	if stdout.Len() != 0 {
-	//		t.Logf("output:\n%s", stdout.String())
-	//	}
-	//	t.Fail()
-	//	return
-	//}
-
 	actual := stdout.Bytes()
 	if config.EmulatorName() == "simavr" {
 		// Strip simavr log formatting.
@@ -645,6 +594,15 @@ func TestWasmExport(t *testing.T) {
 			noOutput:  true, // wasm-unknown cannot produce output
 			command:   true,
 		},
+		// Test buildmode=wasi-legacy with WASI.
+		{
+			name:      "WASIp1-legacy",
+			target:    "wasip1",
+			buildMode: "wasi-legacy",
+			scheduler: "none",
+			file:      "wasmexport-noscheduler.go",
+			command:   true,
+		},
 	}

 	for _, tc := range tests {
@@ -1,4 +1,4 @@
-//go:build nrf || (stm32 && !(stm32f103 || stm32l0x1)) || (sam && atsamd51) || (sam && atsame5x) || esp32c3
+//go:build nrf || (stm32 && !(stm32f103 || stm32l0x1)) || (sam && atsamd51) || (sam && atsame5x) || esp32c3 || tkey

 // If you update the above build constraint, you'll probably also need to update
 // src/runtime/rand_hwrng.go.
@@ -17,6 +17,37 @@ import (
 	"time"
 )

+const (
+	VersionTLS10 = 0x0301
+	VersionTLS11 = 0x0302
+	VersionTLS12 = 0x0303
+	VersionTLS13 = 0x0304
+
+	// Deprecated: SSLv3 is cryptographically broken, and is no longer
+	// supported by this package. See golang.org/issue/32716.
+	VersionSSL30 = 0x0300
+)
+
+// VersionName returns the name for the provided TLS version number
+// (e.g. "TLS 1.3"), or a fallback representation of the value if the
+// version is not implemented by this package.
+func VersionName(version uint16) string {
+	switch version {
+	case VersionSSL30:
+		return "SSLv3"
+	case VersionTLS10:
+		return "TLS 1.0"
+	case VersionTLS11:
+		return "TLS 1.1"
+	case VersionTLS12:
+		return "TLS 1.2"
+	case VersionTLS13:
+		return "TLS 1.3"
+	default:
+		return fmt.Sprintf("0x%04X", version)
+	}
+}
+
 // CurveID is the type of a TLS identifier for an elliptic curve. See
 // https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-8.
 //
@@ -101,7 +101,13 @@ type Dialer struct {
 //
 // The returned Conn, if any, will always be of type *Conn.
 func (d *Dialer) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
-	return nil, errors.New("tls:DialContext not implemented")
+	switch network {
+	case "tcp", "tcp4":
+	default:
+		return nil, fmt.Errorf("Network %s not supported", network)
+	}
+
+	return net.DialTLS(addr)
 }

 // LoadX509KeyPair reads and parses a public/private key pair from a pair
@@ -0,0 +1,139 @@
+//go:build tkey
+
+// Hand written file based on https://github.com/tillitis/tkey-libs/blob/main/include/tkey/tk1_mem.h
+
+package tkey
+
+import (
+	"runtime/volatile"
+	"unsafe"
+)
+
+// Peripherals
+var (
+	TRNG = (*TRNG_Type)(unsafe.Pointer(TK1_MMIO_TRNG_BASE))
+
+	TIMER = (*TIMER_Type)(unsafe.Pointer(TK1_MMIO_TIMER_BASE))
+
+	UDS = (*UDS_Type)(unsafe.Pointer(TK1_MMIO_UDS_BASE))
+
+	UART = (*UART_Type)(unsafe.Pointer(TK1_MMIO_UART_BASE))
+
+	TOUCH = (*TOUCH_Type)(unsafe.Pointer(TK1_MMIO_TOUCH_BASE))
+
+	TK1 = (*TK1_Type)(unsafe.Pointer(TK1_MMIO_TK1_BASE))
+)
+
+// Memory sections
+const (
+	TK1_ROM_BASE uintptr = 0x00000000
+
+	TK1_RAM_BASE uintptr = 0x40000000
+
+	TK1_MMIO_BASE uintptr = 0xc0000000
+
+	TK1_MMIO_TRNG_BASE uintptr = 0xc0000000
+
+	TK1_MMIO_TIMER_BASE uintptr = 0xc1000000
+
+	TK1_MMIO_UDS_BASE uintptr = 0xc2000000
+
+	TK1_MMIO_UART_BASE uintptr = 0xc3000000
+
+	TK1_MMIO_TOUCH_BASE uintptr = 0xc4000000
+
+	TK1_MMIO_FW_RAM_BASE uintptr = 0xd0000000
+
+	TK1_MMIO_TK1_BASE uintptr = 0xff000000
+)
+
+// Memory section sizes
+const (
+	TK1_RAM_SIZE uintptr = 0x20000
+
+	TK1_MMIO_SIZE uintptr = 0x3fffffff
+)
+
+type TRNG_Type struct {
+	_       [36]byte
+	STATUS  volatile.Register32
+	_       [88]byte
+	ENTROPY volatile.Register32
+}
+
+type TIMER_Type struct {
+	_         [32]byte
+	CTRL      volatile.Register32
+	STATUS    volatile.Register32
+	PRESCALER volatile.Register32
+	TIMER     volatile.Register32
+}
+
+type UDS_Type struct {
+	_    [64]byte
+	DATA [8]volatile.Register32
+}
+
+type UART_Type struct {
+	_         [128]byte
+	RX_STATUS volatile.Register32
+	RX_DATA   volatile.Register32
+	RX_BYTES  volatile.Register32
+	_         [116]byte
+	TX_STATUS volatile.Register32
+	TX_DATA   volatile.Register32
+}
+
+type TOUCH_Type struct {
+	_      [36]byte
+	STATUS volatile.Register32
+}
+
+type TK1_Type struct {
+	NAME0         volatile.Register32
+	NAME1         volatile.Register32
+	VERSION       volatile.Register32
+	_             [16]byte
+	SWITCH_APP    volatile.Register32
+	_             [4]byte
+	LED           volatile.Register32
+	GPIO          volatile.Register16
+	APP_ADDR      volatile.Register32
+	APP_SIZE      volatile.Register32
+	BLAKE2S       volatile.Register32
+	_             [72]byte
+	CDI_FIRST     [8]volatile.Register32
+	_             [32]byte
+	UDI_FIRST     [2]volatile.Register32
+	_             [62]byte
+	RAM_ADDR_RAND volatile.Register16
+	_             [2]byte
+	RAM_DATA_RAND volatile.Register16
+	_             [126]byte
+	CPU_MON_CTRL  volatile.Register16
+	_             [2]byte
+	CPU_MON_FIRST volatile.Register32
+	CPU_MON_LAST  volatile.Register32
+	_             [60]byte
+	SYSTEM_RESET  volatile.Register16
+	_             [66]byte
+	SPI_EN        volatile.Register32
+	SPI_XFER      volatile.Register32
+	SPI_DATA      volatile.Register32
+}
+
+const (
+	TK1_MMIO_TIMER_CTRL_START_BIT = 0
+	TK1_MMIO_TIMER_CTRL_STOP_BIT  = 1
+	TK1_MMIO_TIMER_CTRL_START     = 1 << TK1_MMIO_TIMER_CTRL_START_BIT
+	TK1_MMIO_TIMER_CTRL_STOP      = 1 << TK1_MMIO_TIMER_CTRL_STOP_BIT
+
+	TK1_MMIO_TK1_LED_R_BIT = 2
+	TK1_MMIO_TK1_LED_G_BIT = 1
+	TK1_MMIO_TK1_LED_B_BIT = 0
+
+	TK1_MMIO_TK1_GPIO1_BIT = 0
+	TK1_MMIO_TK1_GPIO2_BIT = 1
+	TK1_MMIO_TK1_GPIO3_BIT = 2
+	TK1_MMIO_TK1_GPIO4_BIT = 3
+)
@@ -7,15 +7,13 @@ import (
 	"time"
 )

-// change these to test a different UART or pins if available
 var (
 	uart = machine.Serial
-	tx   = machine.UART_TX_PIN
-	rx   = machine.UART_RX_PIN
 )

 func main() {
-	uart.Configure(machine.UARTConfig{TX: tx, RX: rx})
+	// use default settings for UART
+	uart.Configure(machine.UARTConfig{})
 	uart.Write([]byte("Echo console enabled. Type something then press enter:\r\n"))

 	input := make([]byte, 64)
@@ -13,11 +13,11 @@ func main() {
 		Stereo:      true,
 	})

-	data := make([]uint32, 64)
+	data := make([]uint16, 64)

 	for {
 		// get the next group of samples
-		machine.I2S0.Read(data)
+		machine.I2S0.ReadMono(data)

 		println("data", data[0], data[1], data[2], data[4], "...")
 	}
@@ -3,7 +3,7 @@ package main
 // This example demonstrates how to use pin change interrupts.
 //
 // This is only an example and should not be copied directly in any serious
-// circuit, because it lacks an important feature: debouncing.
+// circuit, because it only naively implements an important feature: debouncing.
 // See: https://en.wikipedia.org/wiki/Switch#Contact_bounce

 import (
@@ -15,6 +15,8 @@ const (
 	led = machine.LED
 )

+var lastPress time.Time
+
 func main() {

 	// Configure the LED, defaulting to on (usually setting the pin to low will
@@ -29,6 +31,13 @@ func main() {

 	// Set an interrupt on this pin.
 	err := button.SetInterrupt(buttonPinChange, func(machine.Pin) {
+
+		// Ignore events that are too close to the last registered press (debouncing)
+		if time.Since(lastPress) < 100*time.Millisecond {
+			return
+		}
+		lastPress = time.Now()
+
 		led.Set(!led.Get())
 	})
 	if err != nil {
@@ -0,0 +1,7 @@
+package abi
+
+type Type struct {
+	// Intentionally left empty. TinyGo uses a different way to represent types,
+	// so this is unimplementable. The type definition here is purely for
+	// compatibility.
+}
@@ -0,0 +1,72 @@
+package futex
+
+// Cross platform futex implementation.
+// Futexes are supported on all major operating systems and on WebAssembly.
+//
+// For more information, see: https://outerproduct.net/futex-dictionary.html
+
+import (
+	"sync/atomic"
+	"unsafe"
+)
+
+// A futex is a way for userspace to wait with the pointer as the key, and for
+// another thread to wake one or all waiting threads keyed on the same pointer.
+//
+// A futex does not change the underlying value, it only reads it before going
+// to sleep (atomically) to prevent lost wake-ups.
+type Futex struct {
+	atomic.Uint32
+}
+
+// Atomically check for cmp to still be equal to the futex value and if so, go
+// to sleep. Return true if we were definitely awoken by a call to Wake or
+// WakeAll, and false if we can't be sure of that.
+func (f *Futex) Wait(cmp uint32) bool {
+	tinygo_futex_wait((*uint32)(unsafe.Pointer(&f.Uint32)), cmp)
+
+	// We *could* detect a zero return value from the futex system call which
+	// would indicate we got awoken by a Wake or WakeAll call. However, this is
+	// what the manual page has to say:
+	//
+	// > Note that a wake-up can also be caused by common futex usage patterns
+	// > in unrelated code that happened to have previously used the futex
+	// > word's memory location (e.g., typical futex-based implementations of
+	// > Pthreads mutexes can cause this under some conditions). Therefore,
+	// > callers should always conservatively assume that a return value of 0
+	// > can mean a spurious wake-up, and use the futex word's value (i.e., the
+	// > user-space synchronization scheme) to decide whether to continue to
+	// > block or not.
+	//
+	// I'm not sure whether we do anything like pthread does, so to be on the
+	// safe side we say we don't know whether the wakeup was spurious or not and
+	// return false.
+	return false
+}
+
+// Like Wait, but times out after the number of nanoseconds in timeout.
+func (f *Futex) WaitUntil(cmp uint32, timeout uint64) {
+	tinygo_futex_wait_timeout((*uint32)(unsafe.Pointer(&f.Uint32)), cmp, timeout)
+}
+
+// Wake a single waiter.
+func (f *Futex) Wake() {
+	tinygo_futex_wake((*uint32)(unsafe.Pointer(&f.Uint32)))
+}
+
+// Wake all waiters.
+func (f *Futex) WakeAll() {
+	tinygo_futex_wake_all((*uint32)(unsafe.Pointer(&f.Uint32)))
+}
+
+//export tinygo_futex_wait
+func tinygo_futex_wait(addr *uint32, cmp uint32)
+
+//export tinygo_futex_wait_timeout
+func tinygo_futex_wait_timeout(addr *uint32, cmp uint32, timeout uint64)
+
+//export tinygo_futex_wake
+func tinygo_futex_wake(addr *uint32)
+
+//export tinygo_futex_wake_all
+func tinygo_futex_wake_all(addr *uint32)
@@ -0,0 +1,49 @@
+//go:build none
+
+// This file is manually included, to avoid CGo which would cause a circular
+// import.
+
+#include <stdint.h>
+
+// This API isn't documented by Apple, but it is used by LLVM libc++ (so should
+// be stable) and has been documented extensively here:
+// https://outerproduct.net/futex-dictionary.html
+
+int __ulock_wait(uint32_t operation, void *addr, uint64_t value, uint32_t timeout_us);
+int __ulock_wait2(uint32_t operation, void *addr, uint64_t value, uint64_t timeout_ns, uint64_t value2);
+int __ulock_wake(uint32_t operation, void *addr, uint64_t wake_value);
+
+// Operation code.
+#define UL_COMPARE_AND_WAIT 1
+
+// Flags to the operation value.
+#define ULF_WAKE_ALL 0x00000100
+#define ULF_NO_ERRNO 0x01000000
+
+void tinygo_futex_wait(uint32_t *addr, uint32_t cmp) {
+    __ulock_wait(UL_COMPARE_AND_WAIT|ULF_NO_ERRNO, addr, (uint64_t)cmp, 0);
+}
+
+void tinygo_futex_wait_timeout(uint32_t *addr, uint32_t cmp, uint64_t timeout) {
+    // Make sure that an accidental use of a zero timeout is not treated as an
+    // infinite timeout. Return if it's zero since it wouldn't be waiting for
+    // any significant time anyway.
+    // Probably unnecessary, but guards against potential bugs.
+    if (timeout == 0) {
+        return;
+    }
+
+    // Note: __ulock_wait2 is available since MacOS 11.
+    // I think that's fine, since the version before that (MacOS 10.15) is EOL
+    // since 2022. Though if needed, we could certainly use __ulock_wait instead
+    // and deal with the smaller timeout value.
+    __ulock_wait2(UL_COMPARE_AND_WAIT|ULF_NO_ERRNO, addr, (uint64_t)cmp, timeout, 0);
+}
+
+void tinygo_futex_wake(uint32_t *addr) {
+    __ulock_wake(UL_COMPARE_AND_WAIT|ULF_NO_ERRNO, addr, 0);
+}
+
+void tinygo_futex_wake_all(uint32_t *addr) {
+    __ulock_wake(UL_COMPARE_AND_WAIT|ULF_NO_ERRNO|ULF_WAKE_ALL, addr, 0);
+}
@@ -0,0 +1,33 @@
+//go:build none
+
+// This file is manually included, to avoid CGo which would cause a circular
+// import.
+
+#include <limits.h>
+#include <stdint.h>
+#include <sys/syscall.h>
+#include <time.h>
+#include <unistd.h>
+
+#define FUTEX_WAIT         0
+#define FUTEX_WAKE         1
+#define FUTEX_PRIVATE_FLAG 128
+
+void tinygo_futex_wait(uint32_t *addr, uint32_t cmp) {
+    syscall(SYS_futex, addr, FUTEX_WAIT|FUTEX_PRIVATE_FLAG, cmp, NULL, NULL, 0);
+}
+
+void tinygo_futex_wait_timeout(uint32_t *addr, uint32_t cmp, uint64_t timeout) {
+    struct timespec ts = {0};
+    ts.tv_sec = timeout / 1000000000;
+    ts.tv_nsec = timeout % 1000000000;
+    syscall(SYS_futex, addr, FUTEX_WAIT|FUTEX_PRIVATE_FLAG, cmp, &ts, NULL, 0);
+}
+
+void tinygo_futex_wake(uint32_t *addr) {
+    syscall(SYS_futex, addr, FUTEX_WAKE|FUTEX_PRIVATE_FLAG, 1, NULL, NULL, 0);
+}
+
+void tinygo_futex_wake_all(uint32_t *addr) {
+    syscall(SYS_futex, addr, FUTEX_WAKE|FUTEX_PRIVATE_FLAG, INT_MAX, NULL, NULL, 0);
+}
@@ -0,0 +1,7 @@
+package unix
+
+const (
+	R_OK = 0x4
+	W_OK = 0x2
+	X_OK = 0x1
+)
@@ -0,0 +1,10 @@
+package unix
+
+import "syscall"
+
+func Eaccess(path string, mode uint32) error {
+	// We don't support this syscall on baremetal or wasm.
+	// Callers are generally able to deal with this since unix.Eaccess also
+	// isn't available on Android.
+	return syscall.ENOSYS
+}
@@ -0,0 +1,12 @@
+package unix
+
+type GetRandomFlag uintptr
+
+const (
+	GRND_NONBLOCK GetRandomFlag = 0x0001
+	GRND_RANDOM   GetRandomFlag = 0x0002
+)
+
+func GetRandom(p []byte, flags GetRandomFlag) (n int, err error) {
+	panic("todo: unix.GetRandom")
+}
@@ -0,0 +1,41 @@
+package task
+
+// Atomics implementation for cooperative systems. The atomic types here aren't
+// actually atomic, they assume that accesses cannot be interrupted by a
+// different goroutine or interrupt happening at the same time.
+
+type atomicIntegerType interface {
+	uintptr | uint32 | uint64
+}
+
+type pseudoAtomic[T atomicIntegerType] struct {
+	v T
+}
+
+func (x *pseudoAtomic[T]) Add(delta T) T { x.v += delta; return x.v }
+func (x *pseudoAtomic[T]) Load() T       { return x.v }
+func (x *pseudoAtomic[T]) Store(val T)   { x.v = val }
+func (x *pseudoAtomic[T]) CompareAndSwap(old, new T) (swapped bool) {
+	if x.v != old {
+		return false
+	}
+	x.v = new
+	return true
+}
+func (x *pseudoAtomic[T]) Swap(new T) (old T) {
+	old = x.v
+	x.v = new
+	return
+}
+
+// Uintptr is an atomic uintptr when multithreading is enabled, and a plain old
+// uintptr otherwise.
+type Uintptr = pseudoAtomic[uintptr]
+
+// Uint32 is an atomic uint32 when multithreading is enabled, and a plain old
+// uint32 otherwise.
+type Uint32 = pseudoAtomic[uint32]
+
+// Uint64 is an atomic uint64 when multithreading is enabled, and a plain old
+// uint64 otherwise.
+type Uint64 = pseudoAtomic[uint64]
@@ -0,0 +1,44 @@
+package task
+
+// A futex is a way for userspace to wait with the pointer as the key, and for
+// another thread to wake one or all waiting threads keyed on the same pointer.
+//
+// A futex does not change the underlying value, it only reads it before to prevent
+// lost wake-ups.
+type Futex struct {
+	Uint32
+	waiters Stack
+}
+
+// Atomically check for cmp to still be equal to the futex value and if so, go
+// to sleep. Return true if we were definitely awoken by a call to Wake or
+// WakeAll, and false if we can't be sure of that.
+func (f *Futex) Wait(cmp uint32) (awoken bool) {
+	if f.Uint32.v != cmp {
+		return false
+	}
+
+	// Push the current goroutine onto the waiter stack.
+	f.waiters.Push(Current())
+
+	// Pause until the waiters are awoken by Wake/WakeAll.
+	Pause()
+
+	// We were awoken by a call to Wake or WakeAll. There is no chance for
+	// spurious wakeups.
+	return true
+}
+
+// Wake a single waiter.
+func (f *Futex) Wake() {
+	if t := f.waiters.Pop(); t != nil {
+		scheduleTask(t)
+	}
+}
+
+// Wake all waiters.
+func (f *Futex) WakeAll() {
+	for t := f.waiters.Pop(); t != nil; t = f.waiters.Pop() {
+		scheduleTask(t)
+	}
+}
@@ -0,0 +1,43 @@
+package task
+
+type Mutex struct {
+	locked  bool
+	blocked Stack
+}
+
+func (m *Mutex) Lock() {
+	if m.locked {
+		// Push self onto stack of blocked tasks, and wait to be resumed.
+		m.blocked.Push(Current())
+		Pause()
+		return
+	}
+
+	m.locked = true
+}
+
+func (m *Mutex) Unlock() {
+	if !m.locked {
+		panic("sync: unlock of unlocked Mutex")
+	}
+
+	// Wake up a blocked task, if applicable.
+	if t := m.blocked.Pop(); t != nil {
+		scheduleTask(t)
+	} else {
+		m.locked = false
+	}
+}
+
+// TryLock tries to lock m and reports whether it succeeded.
+//
+// Note that while correct uses of TryLock do exist, they are rare,
+// and use of TryLock is often a sign of a deeper problem
+// in a particular use of mutexes.
+func (m *Mutex) TryLock() bool {
+	if m.locked {
+		return false
+	}
+	m.Lock()
+	return true
+}
@@ -0,0 +1,16 @@
+package task
+
+// PMutex is a real mutex on systems that can be either preemptive or threaded,
+// and a dummy lock on other (purely cooperative) systems.
+//
+// It is mainly useful for short operations that need a lock when threading may
+// be involved, but which do not need a lock with a purely cooperative
+// scheduler.
+type PMutex struct {
+}
+
+func (m *PMutex) Lock() {
+}
+
+func (m *PMutex) Unlock() {
+}
@@ -21,11 +21,31 @@ type Task struct {
 	// state is the underlying running state of the task.
 	state state

+	// This is needed for some crypto packages.
+	FipsIndicator uint8
+
 	// DeferFrame stores a pointer to the (stack allocated) defer frame of the
 	// goroutine that is used for the recover builtin.
 	DeferFrame unsafe.Pointer
 }

+// DataUint32 returns the Data field as a uint32. The value is only valid after
+// setting it through SetDataUint32 or by storing to it using DataAtomicUint32.
+func (t *Task) DataUint32() uint32 {
+	return *(*uint32)(unsafe.Pointer(&t.Data))
+}
+
+// SetDataUint32 updates the uint32 portion of the Data field (which could be
+// the first 4 or last 4 bytes depending on the architecture endianness).
+func (t *Task) SetDataUint32(val uint32) {
+	*(*uint32)(unsafe.Pointer(&t.Data)) = val
+}
+
+// DataAtomicUint32 returns the Data field as an atomic-if-needed Uint32 value.
+func (t *Task) DataAtomicUint32() *Uint32 {
+	return (*Uint32)(unsafe.Pointer(&t.Data))
+}
+
 // getGoroutineStackSize is a compiler intrinsic that returns the stack size for
 // the given function and falls back to the default stack size. It is replaced
 // with a load from a special section just before codegen.
@@ -33,3 +53,6 @@ func getGoroutineStackSize(fn uintptr) uintptr

 //go:linkname runtime_alloc runtime.alloc
 func runtime_alloc(size uintptr, layout unsafe.Pointer) unsafe.Pointer
+
+//go:linkname scheduleTask runtime.scheduleTask
+func scheduleTask(*Task)
@@ -52,7 +52,7 @@ type stackState struct {
 func start(fn uintptr, args unsafe.Pointer, stackSize uintptr) {
 	t := &Task{}
 	t.state.initialize(fn, args, stackSize)
-	runqueuePushBack(t)
+	scheduleTask(t)
 }

 //export tinygo_launch
@@ -82,9 +82,6 @@ func (s *state) initialize(fn uintptr, args unsafe.Pointer, stackSize uintptr) {
 	s.csp = unsafe.Add(stack, stackSize)
 }

-//go:linkname runqueuePushBack runtime.runqueuePushBack
-func runqueuePushBack(*Task)
-
 // currentTask is the current running task, or nil if currently in the scheduler.
 var currentTask *Task

@@ -101,15 +101,12 @@ func swapTask(oldStack uintptr, newStack *uintptr)
 //go:extern tinygo_startTask
 var startTask [0]uint8

-//go:linkname runqueuePushBack runtime.runqueuePushBack
-func runqueuePushBack(*Task)
-
 // start creates and starts a new goroutine with the given function and arguments.
 // The new goroutine is scheduled to run later.
 func start(fn uintptr, args unsafe.Pointer, stackSize uintptr) {
 	t := &Task{}
 	t.state.initialize(fn, args, stackSize)
-	runqueuePushBack(t)
+	scheduleTask(t)
 }

 // OnSystemStack returns whether the caller is running on the system stack.
--- a/Show More
+++ b/Show More