all: initial support for LLVM 21

.github/workflows/build-macos.yml

@@ -117,7 +117,7 @@ jobs:
     runs-on: macos-latest
     strategy:
       matrix:
-        version: [16, 17, 18, 19, 20]
+        version: [16, 17, 18, 19, 20, 21]
     steps:
       - name: Set up Homebrew
         uses: Homebrew/actions/setup-homebrew@master
@@ -141,8 +141,8 @@ jobs:
       - name: Check binary
         run: tinygo version
       - name: Build TinyGo (default LLVM)
-        if: matrix.version == 20
+        if: matrix.version == 21
         run: go install
       - name: Check binary
-        if: matrix.version == 20
+        if: matrix.version == 21
         run: tinygo version

.github/workflows/sizediff-install-pkgs.sh

@@ -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-20 main' | sudo tee /etc/apt/sources.list.d/llvm.list
+echo 'deb https://apt.llvm.org/noble/ llvm-toolchain-noble-21 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-20-dev \
-    clang-20 \
-    libclang-20-dev \
-    lld-20
+    llvm-21-dev \
+    clang-21 \
+    libclang-21-dev \
+    lld-21