fix cffi build

.github/workflows/build-cli-release.reusable.yaml

@@ -12,7 +12,9 @@
         type: boolean
         default: true
         required: false
-
+  push:
+    branches:
+      - protoc-fix
 env:
   MACOSX_DEPLOYMENT_TARGET: "10.13"
 
@@ -69,18 +71,47 @@
       #   shell: bash
       #   run: |
       #     ci/ubuntu-install-packages
-      
+
       - uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: stable
           target: ${{ matrix._.target }}
-
+      - uses: Swatinem/rust-cache@v2
+        with:
+          workspaces: engine
+          prefix-key: "v5-rust-${{ matrix._.target }}"
       - uses: actions/setup-go@v5
         with:
           go-version: '1.21'
 
-      - name: Install protoc-gen-go
-        run: go install github.com/golang/protobuf/protoc-gen-go@latest
+      - name: Install protoc-gen-go into .cargo/bin
+        shell: bash
+        run: |
+          # The cross-compile environment sanitizes the PATH, so we install the plugin
+          # directly into a directory that is guaranteed to be in the PATH for cargo.
+          # We also create a symlink from the go/bin to the cargo/bin for consistency.
+          mkdir -p .cargo/bin
+          go install github.com/golang/protobuf/protoc-gen-go@latest
+          cp "$HOME/go/bin/protoc-gen-go" ".cargo/bin/"
+          echo "Installed protoc-gen-go into .cargo/bin:"
+          ls -la .cargo/bin
+
+      - name: Test protoc-gen-go availability
+        id: protoc_gen_go_setup
+        shell: bash
+        run: |
+          echo "Current PATH: $PATH"
+          echo "Go bin directory contents:"
+          ls -la $HOME/go/bin/
+          echo "Which protoc-gen-go:"
+          PROTOC_GEN_GO_PATH=$(which protoc-gen-go)
+          echo "Found protoc-gen-go at: $PROTOC_GEN_GO_PATH"
+          echo "protoc_gen_go_path=$PROTOC_GEN_GO_PATH" >> $GITHUB_OUTPUT
+          echo "Testing protoc can find protoc-gen-go plugin..."
+          # Test that protoc can find the go plugin (this will show an error about missing .proto file, but that's expected)
+          protoc --go_out=/tmp --help | grep -q "go_out" && echo "✅ protoc recognizes --go_out flag" || echo "❌ protoc does not recognize --go_out flag"
+
+
 
       - name: Use Cross
         if: contains(matrix._.os, 'ubuntu')
@@ -106,11 +137,7 @@
           echo "target flag is: ${{ env.TARGET_FLAGS }}"
           echo "target dir is: ${{ env.TARGET_DIR }}"
 
-      - uses: Swatinem/rust-cache@v2
-        with:
-          workspaces: engine
-          prefix-key: "v5-rust-${{ matrix._.target }}"
-
+
       # Build the CLI - Always use static-ssl features
       - name: Build CLI Binary
         # This single step now handles all builds
@@ -121,7 +148,24 @@
         working-directory: engine
 
       - name: Build CFFI Library
-        run: >
+        shell: bash
+        run: |
+          # Set the correct protoc-gen-go path based on whether we're using cross (Linux) or native build
+          if [[ "${{ env.CARGO }}" == "cross" ]]; then
+            # For cross builds (Linux), protoc-gen-go will be installed in the container at /usr/local/bin
+            export PROTOC_GEN_GO_PATH="/usr/local/bin/protoc-gen-go"
+          else
+            # For native builds (macOS), use the host path
+            export PROTOC_GEN_GO_PATH="${{ steps.protoc_gen_go_setup.outputs.protoc_gen_go_path }}"
+          fi
+          echo "Using PROTOC_GEN_GO_PATH: $PROTOC_GEN_GO_PATH"
+
+          # We must use PROTOC_GEN_GO_PATH to explicitly tell the build script
+          # where to find the plugin, as the cross-compile environment is isolated.
+          export GOPATH=$HOME/go
+          export GOBIN=$GOPATH/bin
+          export PATH=$PATH:$GOROOT:$GOPATH:$GOBIN
+
           ${{ env.CARGO }} build --release -p baml_cffi ${{ env.TARGET_FLAGS }}
         working-directory: engine
         # Skip this step on Windows runners

engine/Cross.toml

@@ -0,0 +1,44 @@
+# Cross.toml - Configuration for cross-compilation
+
+# Install Go and protoc-gen-go for Linux targets
+[target.x86_64-unknown-linux-gnu]
+pre-build = [
+  "apt-get update",
+  "apt-get install -y wget",
+  "wget -q https://go.dev/dl/go1.21.13.linux-amd64.tar.gz",
+  "tar -xzf go1.21.13.linux-amd64.tar.gz -C /usr/local",
+  "export PATH=$PATH:/usr/local/go/bin",
+  "/usr/local/go/bin/go install github.com/golang/protobuf/protoc-gen-go@latest",
+  "cp /root/go/bin/protoc-gen-go /usr/local/bin/",
+]
+
+[target.x86_64-unknown-linux-musl]
+pre-build = [
+  "if command -v apk >/dev/null 2>&1; then apk update && apk add wget; elif command -v apt-get >/dev/null 2>&1; then apt-get update && apt-get install -y wget; elif command -v yum >/dev/null 2>&1; then yum install -y wget; fi",
+  "wget -q https://go.dev/dl/go1.21.13.linux-amd64.tar.gz",
+  "tar -xzf go1.21.13.linux-amd64.tar.gz -C /usr/local",
+  "export PATH=$PATH:/usr/local/go/bin",
+  "/usr/local/go/bin/go install github.com/golang/protobuf/protoc-gen-go@latest",
+  "cp /root/go/bin/protoc-gen-go /usr/local/bin/",
+]
+
+[target.aarch64-unknown-linux-gnu]
+pre-build = [
+  "apt-get update",
+  "apt-get install -y wget",
+  "wget -q https://go.dev/dl/go1.21.13.linux-amd64.tar.gz",
+  "tar -xzf go1.21.13.linux-amd64.tar.gz -C /usr/local",
+  "export PATH=$PATH:/usr/local/go/bin",
+  "/usr/local/go/bin/go install github.com/golang/protobuf/protoc-gen-go@latest",
+  "cp /root/go/bin/protoc-gen-go /usr/local/bin/",
+]
+
+[target.aarch64-unknown-linux-musl]
+pre-build = [
+  "if command -v apk >/dev/null 2>&1; then apk update && apk add wget; elif command -v apt-get >/dev/null 2>&1; then apt-get update && apt-get install -y wget; elif command -v yum >/dev/null 2>&1; then yum install -y wget; fi",
+  "wget -q https://go.dev/dl/go1.21.13.linux-amd64.tar.gz",
+  "tar -xzf go1.21.13.linux-amd64.tar.gz -C /usr/local",
+  "export PATH=$PATH:/usr/local/go/bin",
+  "/usr/local/go/bin/go install github.com/golang/protobuf/protoc-gen-go@latest",
+  "cp /root/go/bin/protoc-gen-go /usr/local/bin/",
+]

engine/language_client_cffi/build.rs

@@ -323,6 +323,13 @@ mod protoc_lang_out {
 }
 
 fn main() -> std::io::Result<()> {
+    #[cfg(target_os = "windows")]
+    println!("cargo:rustc-link-lib=dylib=ntdll");
+
+    // The last component of the target triple
+    let target_os = std::env::var("CARGO_CFG_TARGET_OS").unwrap();
+    let is_windows = target_os == "windows";
+
     // Re-run build.rs if these files change.
     println!("cargo:rerun-if-changed=types/cffi.fbs");
     println!("cargo:rerun-if-changed=types/cffi.proto");
@@ -348,10 +355,18 @@ fn main() -> std::io::Result<()> {
         //     ..Default::default()
         // };
 
-        protoc_lang_out::ProtocLangOut::new()
+        let mut protoc = protoc_lang_out::ProtocLangOut::new();
+        protoc
             .lang(lang)
             .input("types/cffi.proto")
-            .out_dir(lang_dir)
+            .out_dir(lang_dir);
+
+        // Allow overriding the protoc-gen-go plugin path
+        if let Ok(path) = std::env::var("PROTOC_GEN_GO_PATH") {
+            protoc.plugin(&path);
+        }
+
+        protoc
             .run()
             .unwrap_or_else(|_| panic!("Failed to generate {lang} bindings"));
     }