Fix: Resolve CI failure during aarch64-linux native build

Author: aakashanandg

.github/workflows/build-native-binaries.yml

@@ -50,8 +50,17 @@ jobs:
         if: matrix.os == 'ubuntu-latest'
         run: |
           sudo apt-get update
-          # This installs the C compiler for aarch64-linux
-          sudo apt-get install -y gcc-aarch64-linux-gnu
+          # GCC cross toolchain and binutils for aarch64
+          sudo apt-get install -y gcc-aarch64-linux-gnu g++-aarch64-linux-gnu binutils-aarch64-linux-gnu
+          # Mingw-w64 cross toolchain for Windows target (x86_64)
+          sudo apt-get install -y gcc-mingw-w64-x86-64 g++-mingw-w64-x86-64
+          # Verify tools exist (helps debugging CI failures)
+          echo "=== cross compiler versions ==="
+          aarch64-linux-gnu-gcc --version || true
+          aarch64-linux-gnu-g++ --version || true
+          x86_64-w64-mingw32-gcc --version || true
+          which aarch64-linux-gnu-gcc || true
+          which x86_64-w64-mingw32-gcc || true
 
       # The cross-compiler step for macOS is removed,
       # as the built-in Clang on macOS runners can handle both Intel and ARM.

spannerlib/wrappers/spannerlib-ruby/Rakefile

@@ -71,6 +71,33 @@ namespace :compile do
         "CGO_ENABLED" => "1" # Ensure CGO is enabled for c-shared
       }
 
+      # Set platform-specific C toolchain environment vars so cgo invokes the correct compiler/assembler/linker.
+      case config[:goos]
+      when "linux"
+        if config[:goarch] == "arm64" || config[:goarch] == "arm" || arch.include?("aarch64")
+          # Use the aarch64 cross-compiler installed via apt (aarch64-linux-gnu-*)
+          env["CC"]     = ENV.fetch("CC", "aarch64-linux-gnu-gcc")
+          env["CXX"]    = ENV.fetch("CXX", "aarch64-linux-gnu-g++")
+          env["AR"]     = ENV.fetch("AR", "aarch64-linux-gnu-ar")
+          env["RANLIB"] = ENV.fetch("RANLIB", "aarch64-linux-gnu-ranlib")
+        else
+          # For x86_64 linux, host gcc should work on linux runners
+          env["CC"] ||= ENV.fetch("CC", "gcc")
+        end
+      when "windows"
+        # Use mingw-w64 cross compiler binaries (installed via apt on linux)
+        if config[:goarch] == "amd64" || arch.include?("mingw") || arch.include?("x64")
+          env["CC"]     = ENV.fetch("CC", "x86_64-w64-mingw32-gcc")
+          env["CXX"]    = ENV.fetch("CXX", "x86_64-w64-mingw32-g++")
+          env["AR"]     = ENV.fetch("AR", "x86_64-w64-mingw32-ar")
+          env["RANLIB"] = ENV.fetch("RANLIB", "x86_64-w64-mingw32-ranlib")
+        end
+      when "darwin"
+        # Note: cross-compiling darwin/arm64 on an x86 mac runner is NOT reliably supported
+        # unless you use osxcross or an ARM mac runner. We try nothing here; rely on runner's clang.
+        env["CC"] ||= ENV.fetch("CC", "clang")
+      end
+
       command = [
         "go", "build",
         "-buildmode=c-shared",