build: add optional Rust and CXX bridge support

.cargo/config.toml.offline

@@ -0,0 +1,32 @@
+# Linux
+[target.aarch64-unknown-linux-musl]
+linker = "aarch64-linux-gnu-gcc"
+
+[target.armv7-unknown-linux-musleabihf]
+linker = "arm-linux-gnueabihf-gcc"
+
+[target.powerpc64le-unknown-linux-musl]
+linker = "powerpc64le-linux-gnu-gcc"
+
+[target.riscv64gc-unknown-linux-musl]
+linker = "riscv64-linux-gnu-gcc"
+
+[target.x86_64-unknown-linux-musl]
+linker = "x86_64-linux-gnu-gcc"
+
+# Windows
+[target.x86_64-pc-windows-gnu]
+linker = "x86_64-w64-mingw32-gcc"
+
+# macOS
+# [target.aarch64-apple-darwin]
+# linker = "aarch64-apple-darwin-gcc"
+
+# [target.x86_64-apple-darwin]
+# linker = "x86_64-apple-darwin-gcc"
+
+[source.crates-io]
+replace-with = "vendored-sources"
+
+[source.vendored-sources]
+# The directory for this source is set to RUST_VENDORED_SOURCES by rust/Makefile.am

.github/workflows/build-depends.yml

@@ -15,6 +15,11 @@ on:
         description: "Short hash of the CI base image manifest for cache busting"
         required: true
         type: string
+      rust-vendor-artifact:
+        description: "Artifact holding freshly generated Rust vendor archives"
+        required: false
+        type: string
+        default: ""
       runs-on:
         description: "Runner label to use (e.g., ubuntu-24.04 or ubuntu-24.04-arm)"
         required: true
@@ -141,8 +146,32 @@ jobs:
         uses: actions/cache/restore@v5
         with:
           path: depends/sources
-          key: depends-sources-${{ hashFiles('depends/packages/*') }}
-          restore-keys: depends-sources-
+          key: depends-sources-v2-${{ hashFiles('depends/packages/*', 'depends/patches/native_cxxbridge/Cargo.lock', 'Cargo.lock') }}
+          restore-keys: depends-sources-v2-
+
+      - name: Restore Rust vendor sources
+        id: rust-vendor-cache
+        if: inputs.build-target == 'linux64_rust'
+        uses: actions/cache/restore@v5
+        with:
+          path: |
+            depends/sources/native_cxxbridge-*-vendored.tar.gz
+            depends/sources/vendored-crates-*.tar.gz
+          key: depends-rust-vendor-sources-${{ hashFiles('depends/Makefile', 'depends/funcs.mk', 'depends/packages/native_cxxbridge.mk', 'depends/packages/native_rust.mk', 'depends/patches/native_cxxbridge/Cargo.lock', 'Cargo.lock') }}
+
+      - name: Download Rust vendor sources
+        if: inputs.build-target == 'linux64_rust' && steps.rust-vendor-cache.outputs.cache-hit != 'true' && inputs.rust-vendor-artifact != ''
+        uses: actions/download-artifact@v8
+        with:
+          name: ${{ inputs.rust-vendor-artifact }}
+          path: depends/sources
+
+      - name: Check Rust vendor sources are present
+        if: inputs.build-target == 'linux64_rust' && steps.rust-vendor-cache.outputs.cache-hit != 'true' && inputs.rust-vendor-artifact == ''
+        run: |
+          echo "::error::Rust vendor source cache missed and no same-run artifact was provided"
+          exit 1
+        shell: bash
 
       - name: Restore SDKs cache
         id: sdk-cache

.github/workflows/build-src.yml

@@ -29,6 +29,11 @@ on:
         required: false
         type: string
         default: ""
+      rust-vendor-artifact:
+        description: "Artifact holding freshly generated Rust vendor archives"
+        required: false
+        type: string
+        default: ""
       sdk-artifact:
         description: "Artifact holding prepared SDKs, used if the cache restore misses"
         required: false
@@ -97,6 +102,30 @@ jobs:
           exit 1
         shell: bash
 
+      - name: Restore Rust vendor sources
+        id: rust-vendor-cache
+        if: inputs.build-target == 'linux64_rust'
+        uses: actions/cache/restore@v5
+        with:
+          path: |
+            depends/sources/native_cxxbridge-*-vendored.tar.gz
+            depends/sources/vendored-crates-*.tar.gz
+          key: depends-rust-vendor-sources-${{ hashFiles('depends/Makefile', 'depends/funcs.mk', 'depends/packages/native_cxxbridge.mk', 'depends/packages/native_rust.mk', 'depends/patches/native_cxxbridge/Cargo.lock', 'Cargo.lock') }}
+
+      - name: Download Rust vendor sources
+        if: inputs.build-target == 'linux64_rust' && steps.rust-vendor-cache.outputs.cache-hit != 'true' && inputs.rust-vendor-artifact != ''
+        uses: actions/download-artifact@v8
+        with:
+          name: ${{ inputs.rust-vendor-artifact }}
+          path: depends/sources
+
+      - name: Check Rust vendor sources are present
+        if: inputs.build-target == 'linux64_rust' && steps.rust-vendor-cache.outputs.cache-hit != 'true' && inputs.rust-vendor-artifact == ''
+        run: |
+          echo "::error::Rust vendor source cache missed and no same-run artifact was provided"
+          exit 1
+        shell: bash
+
       - name: Restore depends cache
         id: depends-cache
         uses: actions/cache/restore@v5

.github/workflows/build.yml

@@ -141,6 +141,18 @@ jobs:
       base-image-digest: ${{ needs.check-skip.outputs.base-image-digest }}
       runs-on: ${{ needs.check-skip.outputs['runner-amd64'] }}
 
+  depends-linux64_rust:
+    name: x86_64-pc-linux-gnu_rust
+    uses: ./.github/workflows/build-depends.yml
+    needs: [check-skip, container, cache-sources]
+    if: ${{ vars.SKIP_LINUX64_RUST == '' }}
+    with:
+      build-target: linux64_rust
+      container-path: ${{ needs.container.outputs.path }}
+      base-image-digest: ${{ needs.check-skip.outputs.base-image-digest }}
+      rust-vendor-artifact: ${{ needs.cache-sources.outputs.rust-vendor-artifact }}
+      runs-on: ${{ needs.check-skip.outputs['runner-amd64'] }}
+
   depends-linux64_multiprocess:
     name: linux64_multiprocess
     uses: ./.github/workflows/build-depends.yml
@@ -222,6 +234,21 @@ jobs:
       depends-artifact: ${{ needs.depends-linux64.outputs.built-artifact }}
       runs-on: ${{ needs.check-skip.outputs['runner-amd64'] }}
 
+  src-linux64_rust:
+    name: linux64_rust-build
+    uses: ./.github/workflows/build-src.yml
+    needs: [check-skip, container, cache-sources, depends-linux64_rust]
+    if: ${{ vars.SKIP_LINUX64_RUST == '' }}
+    with:
+      build-target: linux64_rust
+      container-path: ${{ needs.container.outputs.path }}
+      depends-key: ${{ needs.depends-linux64_rust.outputs.key }}
+      depends-host: ${{ needs.depends-linux64_rust.outputs.host }}
+      depends-dep-opts: ${{ needs.depends-linux64_rust.outputs.dep-opts }}
+      depends-artifact: ${{ needs.depends-linux64_rust.outputs.built-artifact }}
+      rust-vendor-artifact: ${{ needs.cache-sources.outputs.rust-vendor-artifact }}
+      runs-on: ${{ needs.check-skip.outputs['runner-amd64'] }}
+
   src-linux64_asan:
     name: linux64_asan-build
     uses: ./.github/workflows/build-src.yml

.github/workflows/cache-depends-sources.yml

@@ -8,6 +8,10 @@ on:
         required: false
         type: string
         default: ubuntu-24.04-arm
+    outputs:
+      rust-vendor-artifact:
+        description: "Artifact holding freshly generated Rust vendor archives"
+        value: ${{ jobs.cache-sources.outputs.rust-vendor-artifact }}
   schedule:
     # Run daily at 6 AM UTC on the default branch to keep cache warm
     - cron: '0 6 * * *'
@@ -18,6 +22,8 @@ jobs:
     # Intentionally keep scheduled cache warming on GitHub-hosted ARM runners.
     # Blacksmith caches are expected to persist long enough without a warmup cron.
     runs-on: ${{ inputs.runs-on || 'ubuntu-24.04-arm' }}
+    outputs:
+      rust-vendor-artifact: ${{ steps.vendor-artifact.outputs.name }}
     steps:
       - name: Checkout code
         uses: actions/checkout@v6
@@ -31,10 +37,43 @@ jobs:
         uses: actions/cache@v5
         with:
           path: depends/sources
-          key: depends-sources-${{ hashFiles('depends/packages/*') }}
-          restore-keys: depends-sources-
+          key: depends-sources-v2-${{ hashFiles('depends/packages/*', 'depends/patches/native_cxxbridge/Cargo.lock', 'Cargo.lock') }}
+          restore-keys: depends-sources-v2-
           lookup-only: true
 
+      - name: Cache Rust vendor sources
+        id: rust-vendor-cache
+        uses: actions/cache@v5
+        with:
+          path: |
+            depends/sources/native_cxxbridge-*-vendored.tar.gz
+            depends/sources/vendored-crates-*.tar.gz
+          key: depends-rust-vendor-sources-${{ hashFiles('depends/Makefile', 'depends/funcs.mk', 'depends/packages/native_cxxbridge.mk', 'depends/packages/native_rust.mk', 'depends/patches/native_cxxbridge/Cargo.lock', 'Cargo.lock') }}
+
       - name: Download sources
-        if: steps.cache-check.outputs.cache-hit != 'true'
-        run: make -C depends download
+        if: |
+          steps.cache-check.outputs.cache-hit != 'true' ||
+          steps.rust-vendor-cache.outputs.cache-hit != 'true'
+        run: |
+          make -C depends RUST=1 download
+          # The cache producer normally runs on ARM, while the Rust consumer
+          # runs on x86_64. Native Rust is selected from the build architecture,
+          # so fetch the x86_64 compiler archive explicitly as well.
+          make -C depends BUILD=x86_64-pc-linux-gnu RUST=1 download-one
+
+      - name: Select Rust vendor artifact
+        id: vendor-artifact
+        if: github.event_name != 'schedule' && steps.rust-vendor-cache.outputs.cache-hit != 'true'
+        run: echo "name=depends-rust-vendor-sources-${{ github.run_id }}" >> "$GITHUB_OUTPUT"
+
+      - name: Upload Rust vendor sources
+        if: steps.vendor-artifact.outputs.name != ''
+        uses: actions/upload-artifact@v6
+        with:
+          name: ${{ steps.vendor-artifact.outputs.name }}
+          path: |
+            depends/sources/native_cxxbridge-*-vendored.tar.gz
+            depends/sources/vendored-crates-*.tar.gz
+          compression-level: 0
+          retention-days: 1
+          overwrite: true

.gitignore

@@ -181,3 +181,27 @@ compile_commands.json
 # Linux perf profiling artifacts
 perf.data
 perf.data.old
+
+# Generated by Cargo
+/target/
+/rust/target/
+
+# Cargo configuration
+/.cargo/.configured-for-*
+/.cargo/config
+/.cargo/config.toml
+/.cargo/dash-build.toml
+/.cargo/*-linker
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
+# Generated by cargo mutants
+# Contains mutation testing data
+**/mutants.out*/
+
+# FFI bridge
+/rust/*/gen/