Build the gfxstream host backend on macOS with CI

.bazelrc

@@ -1,6 +1,12 @@
 # TODO: fixup shared library usage.
 build --noexperimental_link_static_libraries_once
 
+# Raise the macOS deployment target. The default (10.11) is no longer supported
+# by the current SDK's libc++, which turns into a -Werror build failure. Applies
+# to both target and exec (host) configurations. No effect on non-macOS builds.
+build --macos_minimum_os=11.0
+build --host_macos_minimum_os=11.0
+
 # Graphics testing environments options:
 #
 #  * <default>

.github/workflows/presubmit.yaml

@@ -6,6 +6,9 @@ on:
     branches-ignore:
       - main  # push events to main branch occur after PRs are merged, when the same checks were run
 
+permissions:
+  contents: read
+
 concurrency:
   # limits the workflow to a single run per branch/PR
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -18,8 +21,12 @@ jobs:
     steps:
     - name: Checkout repository
       uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
     - name: Install go
-      uses: actions/setup-go@v6
+      uses: actions/setup-go@924ae3a1cded613372ab5595356fb5720e22ba16  # v6.5.0
       with:
         go-version: '1.23.1'
     - name: Install buildozer
@@ -50,7 +57,7 @@ jobs:
     with:
       # TODO(b/475886246): fix and remove `detect_leaks=0`
       # TODO(b/475885975): fix and remove `detect_odr_violation=0`
-      additional-bazel-args: --config=asan --test_env="ASAN_OPTIONS=detect_leaks=0:detect_odr_violation=0"
+      additional-bazel-args: --config=asan --test_env=ASAN_OPTIONS=detect_leaks=0:detect_odr_violation=0
       runner: ubuntu-22.04
 
   run-gfxstream-bazel-tests-arm:
@@ -60,15 +67,36 @@ jobs:
       # The arm runner is too slow:
       run-tests: false
 
+  run-gfxstream-bazel-build-macos:
+    uses: ./.github/workflows/presubmit_bazel.yml
+    with:
+      runner: macos-26
+      # macOS can not build the full target graph: the Linux-only mesa/libdrm
+      # guest dependencies and swiftshader's bundled LLVM (which has no macOS
+      # config) do not build on Darwin. Build the host backend libraries, which
+      # are the macOS deliverable and mirror the CMake/Meson host builds below.
+      build-targets: >-
+        //host:gfxstream_backend_static
+        //host:gfxstream_backend_shared
+        //host:gfxstream_backend
+      # Nothing is run yet: this job exists to keep the macOS host build
+      # compiling. Tests need a graphics driver environment that macOS does not
+      # have here yet.
+      run-tests: false
+
   run-gfxstream-cmake-build:
     runs-on: ubuntu-22.04
     steps:
     - name: Free disk space
-      uses: jlumbroso/free-disk-space@v1.3.1
+      uses: jlumbroso/free-disk-space@54081f138730dfa15788a46383842cd2f914a1be  # v1.3.1
       with:
         tool-cache: true
     - name: Checkout repository
       uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
     - name: Install toolchain dependencies
       run: sudo bash toolchain/cmake/install_toolchain_dependencies.sh
     - name: Configure Build
@@ -81,15 +109,40 @@ jobs:
         cd build && \
         ninja
 
+  run-gfxstream-cmake-build-macos:
+    runs-on: macos-26
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
+    - name: Install toolchain dependencies
+      run: brew install cmake ninja
+    - name: Configure Build
+      run: |
+        mkdir build && \
+        cd build && \
+        cmake .. -G Ninja
+    - name: Build
+      run: |
+        cd build && \
+        ninja
+
   run-gfxstream-meson-build:
     runs-on: ubuntu-22.04
     steps:
     - name: Free disk space
-      uses: jlumbroso/free-disk-space@v1.3.1
+      uses: jlumbroso/free-disk-space@54081f138730dfa15788a46383842cd2f914a1be  # v1.3.1
       with:
         tool-cache: true
     - name: Checkout repository
       uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
     - name: Install toolchain dependencies
       run: sudo bash toolchain/meson/install_toolchain_dependencies.sh
     - name: Configure Build
@@ -102,17 +155,41 @@ jobs:
       run: |
         meson compile -C build
 
+  run-gfxstream-meson-build-macos:
+    runs-on: macos-26
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
+    - name: Install toolchain dependencies
+      run: brew install meson ninja molten-vk vulkan-loader
+    - name: Configure Build
+      run: |
+        meson setup \
+          -Ddefault_library=static \
+          -Dgfxstream-build=host \
+          build
+    - name: Build
+      run: |
+        meson compile -C build
+
   run-gfxstream-meson-build-windows:
     runs-on: windows-latest
     defaults:
       run:
         shell: msys2 {0}
     steps:
       - name: Checkout current PR branch
-        uses: actions/checkout@v6
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
         with:
           ref: ${{ github.event.pull_request.head.sha }}
-      - uses: msys2/setup-msys2@v2
+          # No step needs the token afterwards, so do not leave it
+          # behind in .git/config.
+          persist-credentials: false
+      - uses: msys2/setup-msys2@66cd2cce69caa17b53920067426061ca1de3a884  # v2.32.0
         with:
           msystem: UCRT64
           update: true

.github/workflows/presubmit_bazel.yml

@@ -13,37 +13,59 @@ on:
         type: string
         default: ''
 
+      # Which targets to build. Defaults to everything, but platforms that can
+      # not build the full target graph (e.g. macOS, which lacks the Linux-only
+      # mesa/libdrm/guest dependencies) can override this with a curated list.
+      build-targets:
+        type: string
+        default: '...'
+
       # Whether or not to run the `bazel test` step:
       run-tests:
         type: boolean
         default: true
 
+permissions:
+  contents: read
+
 jobs:
   presubmit_bazel_workflow:
     runs-on: ${{ inputs.runner }}
     steps:
     - name: Free disk space
-      uses: jlumbroso/free-disk-space@v1.3.1
+      if: runner.os == 'Linux'
+      uses: jlumbroso/free-disk-space@54081f138730dfa15788a46383842cd2f914a1be  # v1.3.1
       with:
         tool-cache: true
 
     - name: Checkout repository
       uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8  # v6.0.1
+      with:
+        # No step needs the token afterwards, so do not leave it
+        # behind in .git/config.
+        persist-credentials: false
 
-    - name: Install bazel
+    - name: Install bazel (Linux)
+      if: runner.os == 'Linux'
       run: sudo bash toolchain/bazel/install_bazel.sh
 
-    - name: Install toolchain dependencies
+    - name: Install toolchain dependencies (Linux)
+      if: runner.os == 'Linux'
       run: sudo bash toolchain/bazel/install_toolchain_dependencies.sh
 
-    - name: Install runtime dependencies
+    - name: Install runtime dependencies (Linux)
+      if: runner.os == 'Linux'
       run: sudo apt-get install -y libvulkan1
 
+    - name: Install bazel (macOS)
+      if: runner.os == 'macOS'
+      run: brew install bazelisk
+
     - name: Load cache config
       run: cat .config/cache-config.env >> $GITHUB_ENV
 
     - name: Mount Bazel cache
-      uses: actions/cache/restore@v5
+      uses: actions/cache/restore@caa296126883cff596d87d8935842f9db880ef25  # v5.1.0
       with:
         path: "~/bazel-disk-cache"
         key: ${{ format('{0}-{1}-bazel-disk-cache-{2}-{3}-{4}-', runner.os, runner.arch, env.CACHE_VERSION, github.ref_name, github.sha) }}
@@ -53,15 +75,24 @@ jobs:
           ${{ format('{0}-{1}-bazel-disk-cache-{2}-', runner.os, runner.arch, env.CACHE_VERSION) || '' }}
 
     - name: Build
+      # Workflow inputs reach the script through the environment rather than
+      # being expanded into it, so that their contents can never be parsed as
+      # shell code. They are deliberately left unquoted below so that the shell
+      # still splits them into separate arguments.
+      env:
+        BUILD_TARGETS: ${{ inputs.build-targets }}
+        ADDITIONAL_BAZEL_ARGS: ${{ inputs.additional-bazel-args }}
       run: |
-        bazel build ... \
+        bazel build $BUILD_TARGETS \
           --disk_cache=$HOME/bazel-disk-cache \
           --graphics_drivers=gles_angle_vulkan_swiftshader \
           --verbose_failures \
-          ${{ inputs.additional-bazel-args }}
+          $ADDITIONAL_BAZEL_ARGS
 
     - name: Test
       if: ${{ inputs.run-tests }}
+      env:
+        ADDITIONAL_BAZEL_ARGS: ${{ inputs.additional-bazel-args }}
       run: |
         bazel test \
           --disk_cache=$HOME/bazel-disk-cache \
@@ -74,4 +105,4 @@ jobs:
           host/vulkan:vk_common_operations_tests \
           host/vulkan:vk_format_utils_tests \
           tests/end2end:gfxstream_end2end_tests \
-          ${{ inputs.additional-bazel-args }}
+          $ADDITIONAL_BAZEL_ARGS

CMakeLists.txt

@@ -47,9 +47,6 @@ option(BUILD_GRAPHICS_DETECTOR "Build the graphics detector utility" OFF)
 if (WIN32)
     add_definitions("-DUNICODE -D_UNICODE -DNOMINMAX -DEMUGL_BUILD -DVK_USE_PLATFORM_WIN32_KHR -DBUILDING_EMUGL_COMMON_SHARED")
 endif()
-if (APPLE)
-    add_definitions("-DVK_USE_PLATFORM_METAL_EXT -DVK_USE_PLATFORM_MACOS_MVK")
-endif()
 
 option(VIRGL_RENDERER_UNSTABLE_APIS "Use unstable virglrenderer APIs" ON)
 if(VIRGL_RENDERER_UNSTABLE_APIS)

MODULE.bazel

@@ -15,11 +15,29 @@ bazel_dep(name = "abseil-cpp", version = "20260107.0", dev_dependency = True)
 bazel_dep(name = "aspect_bazel_lib", version = "2.22.5", dev_dependency = True)
 bazel_dep(name = "bazel_skylib", version = "1.7.1", dev_dependency = True)
 bazel_dep(name = "toolchains_llvm", version = "1.6.0", dev_dependency = True)
+bazel_dep(name = "apple_support", version = "1.21.0", repo_name = "build_bazel_apple_support", dev_dependency = True)
 bazel_dep(name = "rules_python", version = "1.5.0", dev_dependency = True)
 bazel_dep(name = "rules_shell", version = "0.6.1", dev_dependency = True)
 bazel_dep(name = "rules_rust", version = "0.68.1", dev_dependency = True)
 bazel_dep(name = "zlib", version = "1.3.1.bcr.3", dev_dependency = True)
 
+# Register the Apple CC (Xcode) toolchain so that `objc_library`/`.mm` targets can
+# be compiled on macOS. The hermetic LLVM toolchain registered below does not
+# support Objective-C compilation. This must be registered before the LLVM
+# toolchain so that it is selected first when targeting macOS; the Apple toolchain
+# is constrained to Apple platforms, so Linux/other builds still use LLVM.
+apple_cc_configure = use_extension(
+    "@build_bazel_apple_support//crosstool:setup.bzl",
+    "apple_cc_configure_extension",
+    dev_dependency = True,
+)
+use_repo(apple_cc_configure, "local_config_apple_cc_toolchains")
+
+register_toolchains(
+    "@local_config_apple_cc_toolchains//:all",
+    dev_dependency = True,
+)
+
 llvm = use_extension("@toolchains_llvm//toolchain/extensions:llvm.bzl", "llvm", dev_dependency = True)
 llvm.toolchain(
     llvm_version = "18.1.8",

common/base/BUILD.bazel

@@ -36,6 +36,9 @@ objc_library(
     srcs = [
         "system-native-mac.mm",
     ],
+    # These sources use manual reference counting (retain/release, CFRelease),
+    # so disable ARC which objc_library enables by default.
+    copts = ["-fno-objc-arc"],
     sdk_frameworks = [
         "IOKit",
         "AppKit",

common/base/SharedMemory_posix.cpp

@@ -55,7 +55,10 @@ SharedMemory::SharedMemory(const std::string& name, size_t size) {
         mName = PathUtils::recompose(PathUtils::decompose(std::move(path)));
     } else {
         mShareType = ShareType::SHARED_MEMORY;
-        mName = name;
+        // POSIX.1-2017 (System Interfaces) requires shm_open() names to begin
+        // with a '/' character to avoid implementation-defined behavior.
+        // Normalize unconditionally so callers don't need to care about it.
+        mName = (!name.empty() && name[0] != '/') ? ("/" + name) : name;
     }
 }
 
@@ -111,7 +114,9 @@ int SharedMemory::openInternal(int oflag, int mode, bool doMapping) {
     int err = 0;
     struct stat sb;
     if (mShareType == ShareType::SHARED_MEMORY) {
-#if defined(HAVE_MEMFD_CREATE)
+#if defined(__APPLE__)
+        mFd = ::shm_open(mName.c_str(), oflag, mode);
+#elif defined(HAVE_MEMFD_CREATE)
         mFd = memfd_create(mName.c_str(), MFD_CLOEXEC | MFD_ALLOW_SEALING);
 #else
         mFd = syscall(__NR_memfd_create, mName.c_str(), FD_CLOEXEC);

common/base/meson.build

@@ -27,6 +27,11 @@ if host_machine.system() == 'windows'
   files_lib_common_base += 'SharedMemory_win32.cpp'
   files_lib_common_base += 'Thread_win32.cpp'
   files_lib_common_base += 'Win32UnicodeString.cpp'
+elif host_machine.system() == 'darwin'
+  files_lib_common_base += 'SharedMemory_posix.cpp'
+  files_lib_common_base += 'Thread_pthread.cpp'
+  files_lib_common_base += 'system-native-mac.mm'
+  common_base_deps += dependency('appleframeworks', modules: ['Foundation', 'AppKit', 'IOKit'])
 else
   files_lib_common_base += 'SharedMemory_posix.cpp'
   files_lib_common_base += 'Thread_pthread.cpp'

host/BUILD.bazel

@@ -107,6 +107,9 @@ objc_library(
     ],
     copts = GFXSTREAM_HOST_COPTS + [
         "-Wno-deprecated-declarations",
+        # These sources use manual reference counting, so disable ARC which
+        # objc_library enables by default.
+        "-fno-objc-arc",
     ],
     defines = GFXSTREAM_HOST_DEFINES,
     sdk_frameworks = [

host/CMakeLists.txt

@@ -144,10 +144,12 @@ target_link_libraries(
         gfxstream_openglesdispatch
         gfxstream-gl-server
         gfxstream-vulkan-server
-        gfxstream_xcb_headers
         GLES_CM_translator_static
         renderControl_dec
         )
+if(NOT APPLE AND NOT WIN32)
+    target_link_libraries(gfxstream_backend_static PUBLIC gfxstream_xcb_headers)
+endif()
 
 target_include_directories(
         gfxstream_backend_static
@@ -357,18 +359,14 @@ endfunction()
             Vulkan_unittests
             PUBLIC
             "-framework AppKit")
-    endif()
-    discover_tests(
-            Vulkan_unittests
-            WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
-
-    if (APPLE)
-        target_compile_definitions(Vulkan_unittests PRIVATE -DVK_USE_PLATFORM_METAL_EXT)
     elseif (QNX)
         target_compile_definitions(Vulkan_unittests PRIVATE -DVK_USE_PLATFORM_SCREEN_QNX)
     elseif (UNIX)
         target_compile_definitions(Vulkan_unittests PRIVATE -DVK_USE_PLATFORM_XCB_KHR)
     endif()
+    discover_tests(
+            Vulkan_unittests
+            WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
 
 
     file(GLOB Vulkan_unittests_datafiles "vulkan/testdata/*.png")