fix(ci): produce static musl binary via zig cross-compilation

.github/workflows/release.yml

@@ -4,9 +4,6 @@ on:
   push:
     tags:
       - 'v*.*.*'
-  pull_request:
-    branches:
-      - develop
 
 permissions:
   contents: write
@@ -45,14 +42,83 @@ jobs:
           cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
           cmake --build build --target task_executable
 
-      - name: Build task binary (Linux — native)
+      - name: Install dependencies (Linux)
+        if: runner.os == 'Linux'
+        run: |
+          sudo apt-get update -q
+          sudo apt-get install -y cmake clang libclang-dev uuid-dev
+
+      - name: Isolate UUID headers
+        if: runner.os == 'Linux'
+        run: |
+          sudo mkdir -p /opt/musl-includes/uuid
+          sudo cp /usr/include/uuid/uuid.h /opt/musl-includes/uuid/
+
+      - name: Set up Rust musl target
+        if: runner.os == 'Linux'
+        run: rustup target add x86_64-unknown-linux-musl
+
+      - name: Set up Zig
+        if: runner.os == 'Linux'
+        uses: mlugg/setup-zig@v1
+        with:
+          version: "0.14.0"
+
+      - name: Create musl-cc/musl-cxx wrappers
+        if: runner.os == 'Linux'
+        run: |
+          sudo tee /usr/local/bin/musl-cc > /dev/null << 'WRAPPER'
+          #!/bin/bash
+          args=()
+          skip_next=0
+          for arg in "$@"; do
+              [ "$skip_next" = "1" ] && { skip_next=0; continue; }
+              [ "$arg" = "-target" ] && { skip_next=1; continue; }
+              [[ "$arg" == --target=* ]] && continue
+              args+=("$arg")
+          done
+          exec zig cc -target x86_64-linux-musl "${args[@]}"
+          WRAPPER
+          sudo tee /usr/local/bin/musl-cxx > /dev/null << 'WRAPPER'
+          #!/bin/bash
+          args=()
+          skip_next=0
+          for arg in "$@"; do
+              [ "$skip_next" = "1" ] && { skip_next=0; continue; }
+              [ "$arg" = "-target" ] && { skip_next=1; continue; }
+              [[ "$arg" == --target=* ]] && continue
+              args+=("$arg")
+          done
+          exec zig c++ -target x86_64-linux-musl "${args[@]}"
+          WRAPPER
+          sudo chmod +x /usr/local/bin/musl-cc /usr/local/bin/musl-cxx
+
+      - name: Build task binary (Linux — musl)
         if: runner.os == 'Linux'
         run: |
           set -e
-          sudo apt-get update -qq
-          sudo apt-get install -y -qq libclang-dev
-          export LIBCLANG_PATH=$(dpkg -L libclang-dev 2>/dev/null | grep 'libclang.*\.so$' | head -1 | xargs dirname || echo /usr/lib/llvm-14/lib)
-          cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
+          printf '%s\n' \
+            'set(CMAKE_SYSTEM_NAME Linux)' \
+            'set(CMAKE_SYSTEM_PROCESSOR x86_64)' \
+            'set(CMAKE_C_COMPILER /usr/local/bin/musl-cc)' \
+            'set(CMAKE_CXX_COMPILER /usr/local/bin/musl-cxx)' \
+            'set(CMAKE_C_COMPILER_WORKS TRUE)' \
+            'set(CMAKE_CXX_COMPILER_WORKS TRUE)' \
+            'set(CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES "")' \
+            'set(CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES "")' \
+            'set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY BOTH)' \
+            'set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE BOTH)' \
+            'set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)' \
+            > /tmp/musl-toolchain.cmake
+          _lib=$(dpkg -L libclang-dev 2>/dev/null | grep 'libclang.*\.so$' | head -1)
+          export LIBCLANG_PATH=${_lib:+$(dirname "$_lib")}
+          export LIBCLANG_PATH=${LIBCLANG_PATH:-/usr/lib/llvm-14/lib}
+          cmake -S . -B build \
+            -DCMAKE_BUILD_TYPE=Release \
+            -DCMAKE_TOOLCHAIN_FILE=/tmp/musl-toolchain.cmake \
+            -DUUID_INCLUDE_DIR=/opt/musl-includes \
+            -DUUID_LIBRARY=/usr/lib/x86_64-linux-gnu/libuuid.so \
+            -DRust_CARGO_TARGET=x86_64-unknown-linux-musl
           cmake --build build --target task_executable -j$(nproc)
 
       - name: Package binary + completions