ci: use musl for Linux binaries

Static linking with musl improves portability - binaries work on any
Linux distro regardless of glibc version (Alpine, older systems, etc).

Author: nikomatsakis

.github/workflows/release-binaries.yml

@@ -3,11 +3,11 @@ name: Release Binaries
 on:
   push:
     tags:
-      - 'elizacp-v*'
-      - 'yopo-v*'
-      - 'sacp-conductor-v*'
-      - 'sacp-tee-v*'
-      - 'sacp-trace-viewer-v*'
+      - "elizacp-v*"
+      - "yopo-v*"
+      - "sacp-conductor-v*"
+      - "sacp-tee-v*"
+      - "sacp-trace-viewer-v*"
 
 env:
   CARGO_TERM_COLOR: always
@@ -21,19 +21,21 @@ jobs:
       matrix:
         include:
           # x86_64
-          - target: x86_64-unknown-linux-gnu
+          - target: x86_64-unknown-linux-musl
             os: ubuntu-latest
             archive: tar.gz
+            musl: true
           - target: x86_64-apple-darwin
             os: macos-latest
             archive: tar.gz
           - target: x86_64-pc-windows-msvc
             os: windows-latest
             archive: zip
           # aarch64
-          - target: aarch64-unknown-linux-gnu
+          - target: aarch64-unknown-linux-musl
             os: ubuntu-latest
             archive: tar.gz
+            musl: true
             cross: true
           - target: aarch64-apple-darwin
             os: macos-latest
@@ -64,12 +66,19 @@ jobs:
         with:
           targets: ${{ matrix.target }}
 
-      - name: Install cross-compilation tools (Linux aarch64)
-        if: matrix.cross
+      - name: Install musl tools
+        if: matrix.musl
         run: |
           sudo apt-get update
-          sudo apt-get install -y gcc-aarch64-linux-gnu
-          echo "CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc" >> $GITHUB_ENV
+          sudo apt-get install -y musl-tools
+
+      - name: Install cross-compilation tools (Linux aarch64 musl)
+        if: matrix.cross
+        run: |
+          # Install aarch64-linux-musl cross compiler
+          curl -fsSL https://musl.cc/aarch64-linux-musl-cross.tgz | sudo tar -xzC /opt
+          echo "/opt/aarch64-linux-musl-cross/bin" >> $GITHUB_PATH
+          echo "CARGO_TARGET_AARCH64_UNKNOWN_LINUX_MUSL_LINKER=aarch64-linux-musl-gcc" >> $GITHUB_ENV
 
       - name: Build binary
         run: cargo build --release --package ${{ steps.extract.outputs.binary }} --target ${{ matrix.target }}