diff --git a/.appveyor.yml b/.appveyor.yml
deleted file mode 100644
index 6a1cd270b..000000000
--- a/.appveyor.yml
+++ /dev/null
@@ -1,179 +0,0 @@
-version: 8.3.0-{build}
-
-image:
-- Visual Studio 2019
-
-environment:
-  STUDIO_VERSION_EDITION: Studio\2019\Community
-  CMAKE_CONFIG: Debug
-  TEST_TARGET: check
-  matrix:
-  - TARGET: cmake
-    CMAKE_OPTIONS: -DCMAKE_BUILD_TYPE=Debug -DBUILD_SHARED_LIBS=OFF -Dbuild_tests=ON -Denable_cplusplus=ON -Denable_gc_assertions=ON -Werror=deprecated -Dwithout_libatomic_ops=ON
-  - TARGET: cmake
-    CMAKE_OPTIONS: -Dbuild_tests=ON -Denable_cplusplus=ON -Denable_throw_bad_alloc_library=OFF -Denable_gc_assertions=ON -Denable_gc_debug=ON -Denable_threads=OFF
-  - TARGET: cmake
-    CFLAGS_EXTRA: -DNO_MSGBOX_ON_ERROR -DNO_MPROTECT_VDB -DGC_READ_ENV_FILE
-    CMAKE_CONFIG: Release
-    CMAKE_OPTIONS: -DCMAKE_BUILD_TYPE=Release -Dbuild_tests=ON -Denable_cplusplus=ON -Denable_large_config=ON -Ddisable_gc_debug=ON -Denable_dynamic_pointer_mask=ON -Denable_rwlock=ON
-  - TARGET: cmake
-    CMAKE_CONFIG: Release
-    CMAKE_OPTIONS: -DCMAKE_BUILD_TYPE=MinSizeRel -Denable_parallel_mark=OFF
-  - TARGET: cmake
-    CMAKE_OPTIONS: -Denable_gc_assertions=ON -Denable_thread_local_alloc=OFF -Ddisable_single_obj_compilation=ON
-  - TARGET: cmake
-    CFLAGS_EXTRA: -DGC_DISABLE_INCREMENTAL
-    CMAKE_OPTIONS: -Denable_gc_assertions=ON -Denable_gcj_support=OFF -Denable_parallel_mark=OFF -Denable_thread_local_alloc=OFF
-  - TARGET: cmake
-    CMAKE_OPTIONS: -A Win32 -Dbuild_tests=ON -Denable_cplusplus=ON -Denable_gc_assertions=ON -Denable_large_config=ON
-  - TARGET: cmake
-    CMAKE_OPTIONS: -A ARM -Denable_cplusplus=ON -Denable_gc_assertions=ON
-  - TARGET: cmake
-    CMAKE_OPTIONS: -A ARM64 -DCMAKE_BUILD_TYPE=Release -Denable_cplusplus=ON
-    CMAKE_CONFIG: Release
-  - TARGET: nmake
-    ARCH: x86
-    NMAKE_OPTIONS: enable_static=1
-  - TARGET: nmake
-    ARCH: x64
-    CFLAGS_EXTRA: /J
-  - TARGET: nmake
-    ARCH: x86
-    NMAKE_OPTIONS: nodebug=1
-  - TARGET: nmake
-    ARCH: x64
-    NMAKE_OPTIONS: disable_threads=1
-  - TARGET: djgpp-no-make
-    CFLAGS_EXTRA: -O3 -DALL_INTERIOR_POINTERS -DNO_EXECUTE_PERMISSION -DENABLE_DISCLAIM -DGC_ATOMIC_UNCOLLECTABLE -DGC_GCJ_SUPPORT
-  - TARGET: dmc
-    CFLAGS_EXTRA: -s -DNO_MSGBOX_ON_ERROR
-  - TARGET: mingw
-  - TARGET: mingw
-    CFLAGS_EXTRA: -D GC_THREADS -D THREAD_LOCAL_ALLOC -D PARALLEL_MARK -D GC_ASSERTIONS -D EMPTY_GETENV_RESULTS -D GC_GCJ_SUPPORT -D USE_MUNMAP -D LARGE_CONFIG -D NO_MSGBOX_ON_ERROR
-    TEST_TARGET: check cord/de
-  - TARGET: mingw
-    CFLAGS_EXTRA: -O3 -march=native -D GC_THREADS -D GC_GCJ_SUPPORT -D GC_TIME_LIMIT=10 -D WINXP_USE_PERF_COUNTER -D NO_MSGBOX_ON_ERROR -D NO_TEST_ENDTHREADEX
-  - TARGET: mingw-shared-no-make
-    CFLAGS_EXTRA: -D GC_THREADS -D GC_ASSERTIONS -D ENABLE_DISCLAIM -D GC_GCJ_SUPPORT -D GC_PREFER_MPROTECT_VDB -D GC_CALL=__stdcall -D GC_CALLBACK=__fastcall -D CONSOLE_LOG -D NO_MSGBOX_ON_ERROR -D USE_RWLOCK -D _WIN32_WINNT=0x0600
-  - TARGET: wcc
-    WCC_SYSTEM: OS2
-    CFLAGS_EXTRA: -DGC_ASSERTIONS
-    ENABLE_STATIC_OPT: "ENABLE_STATIC=1"
-    TEST_TARGET: check-deps
-    WCC_INC_SUBDIR: os2
-  - TARGET: wcc
-    WCC_SYSTEM: MSWIN32
-    CFLAGS_EXTRA: -DCONSOLE_LOG -DUSE_MMAP -DUSE_MUNMAP
-    WCC_INC_SUBDIR: nt
-  - TARGET: mingw-w64
-    CFLAGS_EXTRA: -D NO_MSGBOX_ON_ERROR
-  - TARGET: mingw-w64
-    CFLAGS_EXTRA: -D GC_THREADS -D THREAD_LOCAL_ALLOC -D PARALLEL_MARK -D GC_ASSERTIONS -D GC_GCJ_SUPPORT -D NO_RETRY_GET_THREAD_CONTEXT
-  - TARGET: cygwin
-    CONF_OPTIONS: --enable-cplusplus
-    CFLAGS_EXTRA: -D GCTEST_PRINT_VERBOSE
-  - TARGET: cygwin64
-    CONF_OPTIONS: --disable-threads
-    CFLAGS_EXTRA: -std=c11 -D USE_WINALLOC
-  - TARGET: cygwin64
-    CONF_OPTIONS: --enable-cplusplus
-    CFLAGS_EXTRA: -D GCTEST_PRINT_VERBOSE
-  - TARGET: cygwin
-    CONF_OPTIONS: --enable-cplusplus --disable-munmap --enable-gc-assertions --enable-redirect-malloc
-  - TARGET: cygwin64
-    CFLAGS_EXTRA: -D GC_ALWAYS_MULTITHREADED -D LINT2 -D TEST_MANUAL_VDB
-    CONF_OPTIONS: --enable-cplusplus --enable-gc-assertions --enable-rwlock --disable-shared
-
-clone_depth: 50
-
-install:
-- cmd: git clone --depth=50 https://github.com/ivmai/libatomic_ops.git
-
-build_script:
-- cmd: if [%TARGET%]==[cmake] (
-    mkdir out && cd out
-    && cmake %CMAKE_OPTIONS% -Denable_werror=ON -DCFLAGS_EXTRA="%CFLAGS_EXTRA%" ..
-    && cmake --build . --config %CMAKE_CONFIG% --verbose --parallel )
-- cmd: if [%TARGET%]==[nmake] (
-    "C:\Program Files (x86)\Microsoft Visual %STUDIO_VERSION_EDITION%\VC\Auxiliary\Build\vcvarsall.bat" %ARCH%
-    && nmake /f NT_MAKEFILE %NMAKE_OPTIONS% CFLAGS_EXTRA="/WX %CFLAGS_EXTRA%" )
-- cmd: if [%TARGET%]==[cygwin] (
-    C:\cygwin\bin\bash -e -l -c
-      "cd /cygdrive/c/projects/bdwgc && ./autogen.sh
-       && ./configure %CONF_OPTIONS% --enable-werror && cat include/config.h
-       && make -j CFLAGS_EXTRA='%CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[cygwin64] (
-    C:\cygwin64\bin\bash -e -l -c
-      "cd /cygdrive/c/projects/bdwgc && ./autogen.sh
-       && ./configure %CONF_OPTIONS% --enable-werror && cat include/config.h
-       && make -j CFLAGS_EXTRA='%CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[djgpp-no-make] (
-    appveyor DownloadFile "https://github.com/andrewwutw/build-djgpp/releases/download/v3.4/djgpp-mingw-gcc1220-standalone.zip"
-    && 7z x -o.. djgpp-mingw-gcc1220-standalone.zip > nul
-    && ..\djgpp\setenv.bat
-    && gcc -I include -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA% -c extra/gc.c )
-- cmd: if [%TARGET%]==[dmc] (
-    appveyor DownloadFile "http://ftp.digitalmars.com/Digital_Mars_C++/Patch/dm857c.zip"
-    && 7z x -o.. dm857c.zip > nul && set "path=%cd%\..\dm\bin;%path%"
-    && make -f digimars.mak CFLAGS_EXTRA="-wx %CFLAGS_EXTRA%" )
-- cmd: if [%TARGET%]==[mingw] (
-    C:\MinGW\msys\1.0\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && make -j -f Makefile.direct CC=gcc CFLAGS_EXTRA='-Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[mingw-shared-no-make] (
-    C:\MinGW\msys\1.0\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && gcc -I include -D GC_BUILTIN_ATOMIC -D GC_DLL -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA% -shared -o gc.dll extra/gc.c" )
-- cmd: if [%TARGET%]==[mingw-w64] (
-    C:\msys64\usr\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && make -j -f Makefile.direct CC=gcc CFLAGS_EXTRA='-Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[wcc] (
-    appveyor DownloadFile "https://github.com/open-watcom/open-watcom-v2/releases/download/2023-12-01-Build/ow-snapshot.tar.xz"
-    && 7z x ow-snapshot.tar.xz > nul && 7z x -o..\watcom ow-snapshot.tar > nul
-    && set "watcom=%cd%\..\watcom" && set "path=%cd%\..\watcom\binnt64"
-    && set "include=%cd%\..\watcom\h\%WCC_INC_SUBDIR%;%cd%\..\watcom\h"
-    && wmake -f WCC_MAKEFILE SYSTEM=%WCC_SYSTEM% %ENABLE_STATIC_OPT% CFLAGS_EXTRA="-we %CFLAGS_EXTRA%" )
-
-test_script:
-- cmd: if [%TARGET%]==[cmake] (
-    ctest --build-config %CMAKE_CONFIG% --verbose --parallel 4 )
-- cmd: if [%TARGET%]==[nmake] (
-    "C:\Program Files (x86)\Microsoft Visual %STUDIO_VERSION_EDITION%\VC\Auxiliary\Build\vcvarsall.bat" %ARCH%
-    && nmake /f NT_MAKEFILE %TEST_TARGET% %NMAKE_OPTIONS% CFLAGS_EXTRA="/WX %CFLAGS_EXTRA%"
-    && nmake /f NT_MAKEFILE clean )
-- cmd: if [%TARGET%]==[cygwin] (
-    C:\cygwin\bin\bash -e -l -c
-      "cd /cygdrive/c/projects/bdwgc
-       && make -j check-without-test-driver CFLAGS_EXTRA='%CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[cygwin64] (
-    C:\cygwin64\bin\bash -e -l -c
-      "cd /cygdrive/c/projects/bdwgc
-       && make -j check-without-test-driver CFLAGS_EXTRA='%CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[djgpp-no-make] (
-    ..\djgpp\setenv.bat
-    && gcc -I include -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA% -o cordtest.exe cord/tests/cordtest.c cord/*.c gc.o
-    && gcc -I include -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA% -v -o gctest.exe tests/gctest.c gc.o )
-- cmd: if [%TARGET%]==[dmc] (
-    set "path=%cd%\..\dm\bin;%path%"
-    && make -f digimars.mak %TEST_TARGET% CFLAGS_EXTRA="-wx %CFLAGS_EXTRA%"
-    && type gctest.gc.log cpptest.gc.log
-    && make -f digimars.mak clean )
-- cmd: if [%TARGET%]==[mingw] (
-    C:\MinGW\msys\1.0\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && make -j -f Makefile.direct %TEST_TARGET% CC=gcc CURSES=-lgdi32 CFLAGS_EXTRA='-DGC_NOT_DLL -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[mingw-shared-no-make] (
-    C:\MinGW\msys\1.0\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && gcc -I include -D GC_BUILTIN_ATOMIC -D GC_DLL -Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA% -o gctest.exe tests/gctest.c gc.dll
-       && gctest.exe" )
-- cmd: if [%TARGET%]==[mingw-w64] (
-    C:\msys64\usr\bin\bash -e -l -c
-      "cd /c/projects/bdwgc
-       && make -j -f Makefile.direct %TEST_TARGET% CC=gcc CFLAGS_EXTRA='-Werror -Wall -Wextra -Wpedantic %CFLAGS_EXTRA%'" )
-- cmd: if [%TARGET%]==[wcc] (
-    set "watcom=%cd%\..\watcom" && set "beginlibpath=%cd%\..\watcom\binp\dll"
-    && set "path=%cd%\..\watcom\binnt64;%cd%\..\watcom\binnt"
-    && wmake -f WCC_MAKEFILE %TEST_TARGET% SYSTEM=%WCC_SYSTEM% %ENABLE_STATIC_OPT% CFLAGS_EXTRA="-we %CFLAGS_EXTRA%"
-    && wmake -f WCC_MAKEFILE clean )
diff --git a/.github/workflows/CodeQL.yml b/.github/workflows/CodeQL.yml
deleted file mode 100644
index c53d1c638..000000000
--- a/.github/workflows/CodeQL.yml
+++ /dev/null
@@ -1,35 +0,0 @@
-# CodeQL workflow for GitHub code scanning.
-name: CodeQL
-
-on: [ push, pull_request ]
-
-jobs:
-  analyze:
-    name: Analyze
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ 'c-cpp' ]
-
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Initialize CodeQL
-        uses: github/codeql-action/init@v3
-        with:
-          languages: ${{ matrix.language }}
-
-      - name: Autobuild
-        uses: github/codeql-action/autobuild@v3
-
-      - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v3
-        with:
-          category: "/language:${{ matrix.language }}"
diff --git a/.github/workflows/cmake-build.yml b/.github/workflows/cmake-build.yml
deleted file mode 100644
index d4568e6ce..000000000
--- a/.github/workflows/cmake-build.yml
+++ /dev/null
@@ -1,114 +0,0 @@
-# This workflow is for CMake-based build/test running on multiple platforms.
-name: cmake build
-
-on: [push, pull_request]
-
-jobs:
-  build:
-    name: ${{ matrix.os }} ${{ matrix.c_compiler }} thr:${{ matrix.enable_threads }} rwlock:${{ matrix.enable_rwlock }} redir:${{ matrix.redirect_malloc }} dll:${{ matrix.shared_libs }} cpp:${{ matrix.enable_cplusplus }}
-    runs-on: ${{ matrix.os }}
-    timeout-minutes: 6
-
-    strategy:
-      # Deliver the feedback for all matrix combinations.
-      fail-fast: false
-
-      matrix:
-        os: [ macos-latest, ubuntu-latest, windows-latest ]
-        c_compiler: [ cl, clang, gcc ]
-        cxx_compiler: [ cl, clang++, g++ ]
-        enable_cplusplus: [ off, on ]
-        build_type: [ Release ]
-        disable_gc_debug: [ off ]
-        gc_assertions: [ on ]
-        large_config: [ on ]
-        enable_threads: [ off, on ]
-        enable_rwlock: [ off, on ]
-        redirect_malloc: [ off, on ]
-        shared_libs: [ off, on ]
-        exclude:
-        - os: macos-latest
-          c_compiler: cl
-        - os: macos-latest
-          c_compiler: gcc
-        - os: ubuntu-latest
-          c_compiler: cl
-        - enable_threads: off
-          enable_rwlock: on
-        - c_compiler: cl
-          cxx_compiler: clang++
-        - c_compiler: cl
-          cxx_compiler: g++
-        - c_compiler: clang
-          cxx_compiler: cl
-        - c_compiler: clang
-          cxx_compiler: g++
-        - c_compiler: gcc
-          cxx_compiler: cl
-        - c_compiler: gcc
-          cxx_compiler: clang++
-        - os: macos-latest
-          enable_cplusplus: off
-        - os: ubuntu-latest
-          enable_cplusplus: off
-        - os: windows-latest
-          c_compiler: cl
-          enable_cplusplus: off
-        - os: windows-latest # TODO: replacement operator cannot be inline
-          c_compiler: clang
-          enable_cplusplus: on
-        - os: windows-latest
-          c_compiler: gcc
-          enable_cplusplus: off
-        - os: windows-latest # TODO: support dependency on libatomic_ops
-          c_compiler: cl
-          enable_threads: on
-        include:
-        - os: windows-latest
-          c_compiler: gcc
-          cmake_generator_opt: '-G "Unix Makefiles"'
-        - os: windows-latest
-          c_compiler: clang
-          cmake_generator_opt: '-G "Unix Makefiles"'
-
-    steps:
-    - uses: actions/checkout@v4
-
-    - name: Set reusable strings
-      # Turn repeated input strings into step outputs.
-      id: strings
-      shell: bash
-      run: |
-        echo "build-output-dir=${{ github.workspace }}/build" >> "$GITHUB_OUTPUT"
-
-    - name: Configure CMake
-      # Configure CMake in a 'build' subdirectory.
-      run: >
-        cmake -B ${{ steps.strings.outputs.build-output-dir }}
-        ${{ matrix.cmake_generator_opt }}
-        -DBUILD_SHARED_LIBS=${{ matrix.shared_libs }}
-        -DCMAKE_C_COMPILER=${{ matrix.c_compiler }}
-        -DCMAKE_CXX_COMPILER=${{ matrix.cxx_compiler }}
-        -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
-        -Dbuild_tests=ON
-        -Ddisable_gc_debug=${{ matrix.disable_gc_debug }}
-        -Denable_cplusplus=${{ matrix.enable_cplusplus }}
-        -Denable_gc_assertions=${{ matrix.gc_assertions }}
-        -Denable_large_config=${{ matrix.large_config }}
-        -Denable_redirect_malloc=${{ matrix.redirect_malloc }}
-        -Denable_rwlock=${{ matrix.enable_rwlock }}
-        -Denable_threads=${{ matrix.enable_threads }}
-        -Denable_werror=ON
-        -Werror=dev
-        -S ${{ github.workspace }}
-
-    - name: Build
-      # Build the code with the given configuration.
-      run: >
-        cmake --build ${{ steps.strings.outputs.build-output-dir }}
-        --config ${{ matrix.build_type }} --verbose --parallel
-
-    - name: Test
-      working-directory: ${{ steps.strings.outputs.build-output-dir }}
-      # Execute tests defined by the CMake configuration.
-      run: ctest --build-config ${{ matrix.build_type }} --verbose --parallel 8
diff --git a/.github/workflows/zig-build.yml b/.github/workflows/zig-build.yml
index d78d0e3fc..4ff0ea6cd 100644
--- a/.github/workflows/zig-build.yml
+++ b/.github/workflows/zig-build.yml
@@ -1,18 +1,21 @@
-# This workflow is for zig-based build/test running on Linux/x86_64.
+# This workflow is for zig-based build/test running on Linux and MacOS (x64).
 name: zig build
 
-on: [push, pull_request]
+on: [ push, pull_request ]
 
 jobs:
   build:
-    name: thr:${{ matrix.enable_threads }} rwlock:${{ matrix.enable_rwlock }} redir:${{ matrix.redirect_malloc }} gcdeb:${{ matrix.enable_gc_debug }} munmap:${{ matrix.enable_munmap }} paramark:${{ matrix.parallel_mark }} thrlocal:${{ matrix.thread_local_alloc }}
-    runs-on: ubuntu-latest
-    timeout-minutes: 4
+    name: ${{ matrix.os }} thr:${{ matrix.enable_threads }} rwlock:${{ matrix.enable_rwlock }} redir:${{ matrix.redirect_malloc }} gcdeb:${{ matrix.enable_gc_debug }} munmap:${{ matrix.enable_munmap }} paramark:${{ matrix.parallel_mark }} thrlocal:${{ matrix.thread_local_alloc }} dll:${{ matrix.shared_libs }}
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 6
 
     strategy:
       fail-fast: false
 
       matrix:
+        # TODO: move from nightly to zig 0.12 final when released.
+        zig_version: [ "0.12.0-dev.2076+8fd15c6ca" ]
+        os: [ macos-latest ]#, ubuntu-latest ]
         gc_assertions: [ true ]
         large_config: [ false ]
         enable_threads: [ false, true ]
@@ -23,7 +26,7 @@ jobs:
         enable_munmap: [ false, true ]
         parallel_mark: [ false, true ]
         thread_local_alloc: [ false, true ]
-        shared_libs: [ false ] # FIXME: gctest fail if shared lib
+        shared_libs: [ false, true ]
         exclude:
         - enable_threads: false
           disable_handle_fork: true
@@ -35,13 +38,53 @@ jobs:
           thread_local_alloc: true
         - enable_gc_debug: true # FIXME: some tests fail if gc_debug+redirect
           redirect_malloc: true
+        # The following ones are long-running jobs, thus excluded.
+        - os: macos-latest
+          enable_gc_debug: true
+          enable_rwlock: true
+        # The following ones just to reduce amount of jobs.
+        - enable_munmap: false
+          shared_libs: true
+        - enable_munmap: true
+          enable_threads: false
+          shared_libs: false
+        - enable_gc_debug: true
+          enable_rwlock: true
+          thread_local_alloc: false
+        - os: macos-latest
+          enable_munmap: false
+          enable_threads: false
+        - os: macos-latest
+          enable_munmap: false
+          enable_rwlock: true
+        - os: macos-latest
+          enable_rwlock: true
+          thread_local_alloc: false
+        - os: macos-latest
+          enable_rwlock: true
+          parallel_mark: false
+        - os: macos-latest
+          enable_munmap: false
+          redirect_malloc: false
+        - os: macos-latest
+          enable_threads: true
+          redirect_malloc: false
+          thread_local_alloc: false
+        - os: macos-latest
+          enable_threads: true
+          redirect_malloc: false
+          parallel_mark: false
 
-    # TODO: move from nightly to zig 0.12 final when released.
     steps:
     - uses: actions/checkout@v4
-    - name: "Install zig"
+    - name: "Install zig on Linux/x86_64"
+      if: runner.os == 'Linux'
+      run: |
+        mkdir zig && curl https://ziglang.org/builds/zig-linux-x86_64-${{matrix.zig_version}}.tar.xz | tar Jx --directory=zig --strip-components=1
+    - name: "Install zig on MacOS/x86_64"
+      if: runner.os == 'macOS'
       run: |
-        mkdir zig && curl https://ziglang.org/builds/zig-linux-x86_64-0.12.0-dev.2076+8fd15c6ca.tar.xz | tar Jx --directory=zig --strip-components=1
+        mkdir zig && curl https://ziglang.org/builds/zig-macos-x86_64-${{matrix.zig_version}}.tar.xz | tar Jx --directory=zig --strip-components=1
     - name: Build
       run: >
         zig/zig build
diff --git a/.github/workflows/zig-cross-compile.yml b/.github/workflows/zig-cross-compile.yml
deleted file mode 100644
index 65f48f6b5..000000000
--- a/.github/workflows/zig-cross-compile.yml
+++ /dev/null
@@ -1,110 +0,0 @@
-# This workflow uses Zig and its excellent cross-compilation support to test
-# compiling for multiple platforms. No tests are actually run since it would
-# require emulation.
-name: zig cross-compile
-
-on: [ push, pull_request ]
-
-jobs:
-  build:
-    name: ${{ matrix.ttriple }} thr:${{ matrix.enable_threads }} dll:${{ matrix.shared_libs }}
-    runs-on: ubuntu-latest
-
-    strategy:
-      fail-fast: false
-      matrix:
-        # Some of the triples are commented out just to speedup this workflow.
-        ttriple: [
-          aarch64-linux-gnu,
-          #aarch64-linux-musl,
-          aarch64-windows-gnu,
-          #aarch64_be-linux-gnu,
-          aarch64_be-linux-musl,
-          #arm-linux-gnueabi,
-          arm-linux-gnueabihf,
-          arm-linux-musleabi,
-          #arm-linux-musleabihf,
-          armeb-linux-gnueabi,
-          #armeb-linux-gnueabihf,
-          #armeb-linux-musleabi,
-          armeb-linux-musleabihf,
-          #mips-linux-gnueabi,
-          #mips-linux-gnueabihf,
-          mips-linux-musl,
-          mips64-linux-gnuabi64,
-          #mips64-linux-gnuabin32,
-          mips64-linux-musl,
-          #mips64el-linux-gnuabi64,
-          mips64el-linux-gnuabin32,
-          mips64el-linux-musl,
-          mipsel-linux-gnueabi,
-          #mipsel-linux-gnueabihf,
-          mipsel-linux-musl,
-          #powerpc-linux-gnueabi,
-          powerpc-linux-gnueabihf,
-          #powerpc-linux-musl,
-          powerpc64-linux-gnu,
-          #powerpc64-linux-musl,
-          #powerpc64le-linux-gnu,
-          powerpc64le-linux-musl,
-          riscv64-linux-musl,
-          sparc64-linux-gnu,
-          thumb-linux-gnueabi,
-          #thumb-linux-gnueabihf,
-          #thumb-linux-musleabi,
-          thumb-linux-musleabihf,
-          wasm32-wasi-musl,
-          #x86-linux-gnu,
-          x86-linux-musl,
-          x86-windows-gnu,
-          x86_64-linux-gnu.2.27, # with a glibc version
-          x86_64-linux-gnux32,
-          #x86_64-linux-musl,
-          x86_64-windows-gnu,
-        ]
-        enable_threads: [ false, true ]
-        shared_libs: [ false, true ]
-        exclude:
-        - enable_threads: true
-          ttriple: wasm32-wasi-musl
-        # The following ones have some zig link issue.
-        - shared_libs: true
-          ttriple: aarch64_be-linux-gnu
-        - shared_libs: true
-          ttriple: aarch64_be-linux-musl
-        - shared_libs: true
-          ttriple: armeb-linux-gnueabi
-        - shared_libs: true
-          ttriple: armeb-linux-gnueabihf
-        - shared_libs: true
-          ttriple: armeb-linux-musleabi
-        - shared_libs: true
-          ttriple: armeb-linux-musleabihf
-        - shared_libs: true
-          ttriple: mips64-linux-gnuabin32
-        - shared_libs: true
-          ttriple: mips64el-linux-gnuabin32
-        - shared_libs: true
-          ttriple: powerpc-linux-gnueabi
-        - shared_libs: true
-          ttriple: powerpc-linux-gnueabihf
-        - shared_libs: true
-          ttriple: sparc64-linux-gnu # FIXME: recompile with -fPIC
-        - shared_libs: true
-          ttriple: thumb-linux-gnueabi
-        - shared_libs: true
-          ttriple: thumb-linux-gnueabihf
-        - shared_libs: true
-          ttriple: x86_64-linux-gnux32 # FIXME: recompile with -fPIC
-
-    # TODO: move from nightly to zig 0.12 final when released.
-    steps:
-    - uses: actions/checkout@v4
-    - name: "Install zig"
-      run: |
-        mkdir zig && curl https://ziglang.org/builds/zig-linux-x86_64-0.12.0-dev.2076+8fd15c6ca.tar.xz | tar Jx --directory=zig --strip-components=1
-    - name: Build
-      run: >
-        zig/zig build -Dtarget=${{ matrix.ttriple }}
-        -DBUILD_SHARED_LIBS=${{ matrix.shared_libs }}
-        -Denable_threads=${{ matrix.enable_threads }}
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index c8b4bc477..000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,813 +0,0 @@
-language: cpp
-os: linux
-dist: jammy
-
-jobs:
-  include:
-  - compiler: clang
-    env:
-    - CONF_OPTIONS="--enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-cplusplus"
-  - os: osx
-    env:
-    - CONF_OPTIONS="--enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - env:
-    - COVERITY_SCAN_BRANCH=1
-    addons:
-      coverity_scan:
-        project:
-          name: ivmai/bdwgc
-          version: 8.3.0
-        notification_email: ivmai@mail.ru
-        branch_pattern: master
-        build_command_prepend: "./configure --enable-cplusplus --disable-shared --enable-single-obj-compilation"
-        build_command: make -j check CFLAGS_EXTRA=-DLINT2
-  - addons:
-      apt:
-        packages:
-        - lcov
-    compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-gcov --enable-single-obj-compilation --enable-cplusplus --disable-shared --enable-gc-assertions"
-    - CFLAGS_EXTRA="-D USE_CUSTOM_SPECIFIC"
-    - CC_FOR_CHECK=g++
-    - MAKEFILE_TARGETS="all"
-    - MAKEFILE_TARGETS_CHECK="check"
-    - NO_CLONE_LIBATOMIC_OPS=true
-    - REPORT_COVERAGE=true
-    - TESTS_CUSTOM_RUN=true
-  - env:
-    - MAKEFILE_TARGETS="dist"
-  - os: osx
-    env:
-    - CSA_CHECK=true
-    - CFLAGS_EXTRA="-m32"
-  - compiler: clang
-    language: c
-    env:
-    - CSA_CHECK=true
-    - CFLAGS_EXTRA="-D ALL_INTERIOR_POINTERS -D CHECKSUMS -D DBG_HDRS_ALL -D DEBUG_THREADS -D ENABLE_TRACE -D GC_ALWAYS_MULTITHREADED -D GC_ASSERTIONS -D GC_ATOMIC_UNCOLLECTABLE -D GC_ENABLE_SUSPEND_THREAD -D GC_GCJ_SUPPORT -D GC_PRINT_BACK_HEIGHT -D GC_THREADS -D HANDLE_FORK -D JAVA_FINALIZATION -D KEEP_BACK_PTRS -D MAKE_BACK_GRAPH -D PARALLEL_MARK -D PRINT_BLACK_LIST -D THREAD_LOCAL_ALLOC -D USE_MMAP -D USE_MUNMAP"
-  - dist: xenial
-    env:
-    - CPPCHECK_ENABLE="--enable=unusedFunction -I libatomic_ops/src extra/gc.c tests/*.c"
-  - dist: xenial
-    env:
-    - CPPCHECK_ENABLE="--enable=unusedFunction --force -D GC_BUILTIN_ATOMIC *.cc cord/*.c cord/tests/*.c tests/*.c tests/*.cc"
-    - CPPCHECK_OUT_FILTER="Z"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - dist: xenial
-    env:
-    - CPPCHECK_ENABLE="-j4 --enable=information,performance,portability,style,warning --force -U GC_PRIVATE_H -I libatomic_ops/src a*.c b*.c c*.c d*.c f*.c g*.c h*.c m*.c"
-  - dist: xenial
-    env:
-    - CPPCHECK_ENABLE="-j4 --enable=information,performance,portability,style,warning --force -U GC_PRIVATE_H -I libatomic_ops/src n*.c o*.c p*.c r*.c s*.c t*.c w*.c"
-  - dist: xenial
-    env:
-    - CPPCHECK_ENABLE="-j4 --enable=information,performance,portability,style,warning --force -U GC_PRIVATE_H -I libatomic_ops/src *.cc cord/*.c cord/tests/*.c extra/AmigaOS.c extra/MacOS.c extra/msvc_dbg.c extra/symbian.cpp tests/*.c tests/*.cc tools/*.c"
-  - arch: arm64
-    compiler: clang
-  - arch: arm64
-    compiler: gcc
-  - arch: arm64
-    compiler: clang
-    env:
-    - CFLAGS_EXTRA="-O3"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --disable-shared"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: arm64
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-O3 -D SIMULATE_LOST_SIGNALS -D TRACE_BUF"
-    - CONF_OPTIONS="--enable-cplusplus --disable-gcj-support"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - musl-tools
-    arch: arm64
-    compiler: musl-gcc
-    dist: focal
-    language: c
-    env:
-    - CFLAGS_EXTRA="-O3 -D SOFT_VDB"
-    - CONF_OPTIONS="--enable-gc-assertions"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: arm64
-    compiler: gcc
-    env:
-    - CONF_OPTIONS="--disable-threads"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: arm64
-    addons:
-      apt:
-        packages:
-        - libatomic-ops-dev
-    compiler: gcc
-    env:
-    - CONF_OPTIONS="--with-libatomic-ops=yes --enable-gc-assertions --enable-cplusplus --disable-munmap"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: arm64
-    compiler: clang
-    language: c
-    env:
-    - CFLAGS_EXTRA="-fsanitize=memory,undefined -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-    - TESTS_CUSTOM_RUN=true
-  - arch: arm64
-    compiler: clang
-    env:
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=MinSizeRel -Dbuild_tests=ON -DBUILD_SHARED_LIBS=OFF -Denable_cplusplus=ON -Denable_gc_assertions=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: arm64
-    compiler: gcc
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - arch: ppc64le
-    compiler: clang
-  - arch: ppc64le
-    compiler: gcc
-    env:
-    - CONF_OPTIONS="--disable-disclaim"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: ppc64le
-    compiler: clang
-    env:
-    - CFLAGS_EXTRA="-O3 -D _FORTIFY_SOURCE=2 -D FORCE_MPROTECT_BEFORE_MADVISE -D GC_UNMAPPED_REGIONS_SOFT_LIMIT=120"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: ppc64le
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-O3 -D NO_MPROTECT_VDB"
-    - CONF_OPTIONS="--enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: ppc64le
-    compiler: clang
-    env:
-    - CFLAGS_EXTRA="-D CHECK_SOFT_VDB"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-static --disable-thread-local-alloc"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: ppc64le
-    compiler: clang
-    language: c
-    env:
-    - CFLAGS_EXTRA="-fsanitize=memory,undefined -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--disable-shared"
-    - NO_CLONE_LIBATOMIC_OPS=true
-    - TESTS_CUSTOM_RUN=true
-  - arch: ppc64le
-    compiler: clang
-    env:
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Release -Dbuild_tests=ON -Denable_cplusplus=ON -Denable_gc_assertions=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: ppc64le
-    compiler: clang
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - arch: s390x
-    compiler: clang
-    dist: focal
-  - arch: s390x
-    compiler: gcc
-    dist: focal
-  - addons:
-      apt:
-        packages:
-        - clang-12
-    arch: s390x
-    compiler: clang-12
-    dist: focal
-    env:
-    - CC=clang-12
-    - CXX=clang++-12
-    - CFLAGS_EXTRA="-O3 -flto -D _FORTIFY_SOURCE=2 -D NO_RETRY_SIGNALS"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-dynamic-pointer-mask"
-  - addons:
-      apt:
-        packages:
-        - g++-10
-    arch: s390x
-    compiler: g++-10
-    dist: focal
-    env:
-    - CC=gcc-10
-    - CXX=g++-10
-    - CFLAGS_EXTRA="-O3 -flto=auto -D _FORTIFY_SOURCE=2 -D PREFER_MMAP_PROT_NONE"
-    - CONF_OPTIONS="--enable-cplusplus --disable-shared"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - arch: s390x
-    compiler: gcc
-    dist: focal
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - os: freebsd
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-O3 -D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-cplusplus --enable-gc-assertions --enable-rwlock"
-    - MAKE_NPROC=8
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: freebsd
-    env:
-    - CONF_OPTIONS="--enable-cplusplus"
-    - MAKE_NPROC=8
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: freebsd
-    env:
-    - CONF_OPTIONS="--enable-gc-assertions --disable-shared"
-    - MAKE_NPROC=8
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: freebsd
-    env:
-    - CMAKE_BUILD_OPTIONS="--verbose"
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Release -Denable_cplusplus=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: freebsd
-    compiler: clang
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-    - MAKE_NPROC=8
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-O3 -march=native"
-    - CONF_OPTIONS="--enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: clang
-    env:
-    - CFLAGS_EXTRA="-m32 -funsigned-char -D _FORTIFY_SOURCE=2 -D NO_LONGLONG64"
-    - CONF_OPTIONS="--enable-gc-assertions"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-m32 -D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-mmap --enable-rwlock"
-  - os: osx
-    env:
-    - CFLAGS_EXTRA="-m32 -D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--disable-threads --enable-checksums --disable-munmap --enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CONF_OPTIONS="--disable-threads --enable-checksums --disable-handle-fork --disable-munmap --enable-gc-assertions --enable-large-config --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2 -D DBG_HDRS_ALL -D SHORT_DBG_HDRS"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CFLAGS_EXTRA="-D DBG_HDRS_ALL -D SHORT_DBG_HDRS -D LINT2 -D PRINT_AND_CHECK_INT_LIST -D USE_GETSECTBYNAME"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-handle-fork=manual --disable-throw-bad-alloc-library"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D DEBUG_ADD_DEL_ROOTS -D DEBUG_THREADS -D GC_DEBUG -D GC_LOG_TO_FILE_ALWAYS"
-    - CONF_OPTIONS="--enable-cplusplus"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D BSD_TIME -D DEFAULT_STACK_MAYBE_SMALL -D ENABLE_TRACE -D EMPTY_GETENV_RESULTS -D GC_ALWAYS_MULTITHREADED -D GC_NETBSD_THREADS_WORKAROUND -D CPPCHECK"
-    - CONF_OPTIONS="--enable-cplusplus --enable-gc-assertions"
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-march=native -D _FORTIFY_SOURCE=2 -D DEFAULT_VDB -D TEST_WITH_SYSTEM_MALLOC"
-    - CONF_OPTIONS="--without-libatomic-ops --enable-cplusplus --disable-handle-fork"
-  - addons:
-      apt:
-        packages:
-        - libatomic-ops-dev
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2 -D TEST_PAGES_EXECUTABLE"
-    - CONF_OPTIONS="--with-libatomic-ops=yes --enable-gc-assertions --enable-cplusplus --disable-throw-bad-alloc-library"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CFLAGS_EXTRA="-march=native -D _FORTIFY_SOURCE=2 -D AO_DISABLE_GCC_ATOMICS"
-    - CONF_OPTIONS="--without-libatomic-ops --enable-munmap --enable-cplusplus --enable-static"
-  - compiler: gcc
-    env:
-    - CONF_CFLAGS="-O3 -D _FORTIFY_SOURCE=2 -D AO_USE_PTHREAD_DEFS -D RANDOM_ONE_CPU_CORE"
-    - CONF_OPTIONS="--without-libatomic-ops --enable-gc-assertions --enable-cplusplus --enable-static"
-  - compiler: clang
-    env:
-    - CONF_CFLAGS="-D AO_USE_PTHREAD_DEFS"
-    - CONF_OPTIONS="--without-libatomic-ops"
-  - addons:
-      apt:
-        packages:
-        - libatomic-ops-dev
-    compiler: gcc
-    env:
-    - CONF_CFLAGS="-O3 -D AO_USE_PTHREAD_DEFS -D RANDOM_ONE_CPU_CORE"
-    - CONF_OPTIONS="--with-libatomic-ops=yes --enable-cplusplus"
-    - CFLAGS_EXTRA="-D GC_NO_FINALIZATION"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - libatomic-ops-dev
-    compiler: clang
-    env:
-    - CONF_CFLAGS="-O3 -D AO_USE_PTHREAD_DEFS -D RANDOM_ONE_CPU_CORE"
-    - CONF_OPTIONS="--with-libatomic-ops=yes --enable-gc-assertions --enable-cplusplus --disable-shared --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-funsigned-char -D _FORTIFY_SOURCE=2 -D DONT_ADD_BYTE_AT_END -D GC_TIME_LIMIT=3"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus"
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-m32 -D _FORTIFY_SOURCE=2 -D MARK_BIT_PER_OBJ -D USE_CUSTOM_SPECIFIC"
-    - CONF_OPTIONS="--enable-gc-assertions"
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-D MARK_BIT_PER_OBJ"
-    - CONF_OPTIONS="--enable-cplusplus --enable-rwlock --disable-shared"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2 -D NO_CLOCK -D POINTER_MASK=~0xf"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-handle-fork=manual"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D PROC_VDB -D GC_NO_SYS_FAULT_H -D NO_INCREMENTAL -D DEBUG_DIRTY_BITS"
-    - CONF_OPTIONS="--enable-cplusplus --disable-docs"
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2 -D TEST_MANUAL_VDB"
-    - CONF_OPTIONS="--enable-gc-assertions --disable-parallel-mark"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D TEST_MANUAL_VDB"
-    - CONF_OPTIONS="--enable-gc-assertions --disable-munmap"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2 -D FIND_LEAK -D SKIP_LEAKED_OBJECTS_PRINTING"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D SMALL_CONFIG -D NO_GETENV"
-    - CONF_OPTIONS="--enable-cplusplus"
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-std=c11 -D _FORTIFY_SOURCE=2 -D GC_NO_SIGSETJMP"
-    - CONF_OPTIONS="--disable-threads --enable-gc-assertions"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CONF_OPTIONS="--disable-thread-local-alloc --enable-cplusplus --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-O3 -flto -D _FORTIFY_SOURCE=2 -D NO_MANUAL_VDB"
-    - CONF_OPTIONS="--disable-parallel-mark --disable-thread-local-alloc --enable-gc-assertions --enable-cplusplus"
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-gc-debug --enable-cplusplus"
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--disable-gc-debug --enable-cplusplus"
-  - compiler: clang
-    env:
-    - CONF_OPTIONS="--enable-large-config --enable-cplusplus --disable-shared --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CFLAGS_EXTRA="-D TEST_HANDLE_FORK"
-    - CONF_OPTIONS="--enable-cplusplus --disable-shared --enable-rwlock --enable-static"
-  - os: osx
-    env:
-    - CONF_OPTIONS="--enable-large-config --enable-cplusplus --disable-gc-debug --disable-handle-fork"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-large-config --disable-munmap"
-    - CFLAGS_EXTRA="-m32"
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-large-config --enable-cplusplus --enable-gc-assertions --enable-static"
-    - CFLAGS_EXTRA="-D LINT2 -D NO_VDB_FOR_STATIC_ROOTS -D TEST_REUSE_SIG_SUSPEND"
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-large-config --enable-redirect-malloc --disable-threads"
-    - CFLAGS_EXTRA="-O3"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: clang
-    env:
-    - CONF_OPTIONS="--enable-redirect-malloc --enable-static --disable-threads"
-    - CFLAGS_EXTRA="-m32"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CONF_OPTIONS="--enable-redirect-malloc --enable-cplusplus --enable-static --disable-threads"
-    - CFLAGS_EXTRA="-m32"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-redirect-malloc --enable-gc-debug --enable-cplusplus --enable-gc-assertions"
-  - compiler: clang
-    env:
-    - CONF_OPTIONS="--disable-threads --enable-cplusplus"
-    - CFLAGS_EXTRA="-O3 -march=native"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--disable-static --disable-threads --enable-cplusplus"
-    - CFLAGS_EXTRA="-O3 -march=native -D GC_PREFER_MPROTECT_VDB"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CONF_OPTIONS="--disable-threads --enable-cplusplus"
-    - CFLAGS_EXTRA="-O3 -march=native"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CMAKE_OPTIONS="-Denable_cplusplus=ON -Denable_gc_assertions=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - libatomic-ops-dev
-    compiler: clang
-    env:
-    - CMAKE_OPTIONS="-Denable_cplusplus=ON -Denable_munmap=OFF -Dwith_libatomic_ops=ON"
-  - compiler: gcc
-    env:
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Release -Denable_cplusplus=ON -Denable_large_config=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Debug -DBUILD_SHARED_LIBS=OFF -Denable_gc_debug=ON -Dwithout_libatomic_ops=ON"
-  - compiler: gcc
-    env:
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF -Denable_threads=OFF"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CMAKE_BUILD_OPTIONS="--verbose"
-    - CMAKE_OPTIONS="-Denable_cplusplus=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - os: osx
-    env:
-    - CMAKE_BUILD_OPTIONS="--verbose"
-    - CMAKE_OPTIONS="-DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF -Denable_cplusplus=ON -Denable_gc_assertions=ON -Denable_large_config=ON"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - compiler: gcc
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - os: osx
-    env:
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="check cord/de"
-  - addons:
-      apt:
-        packages:
-        - musl-tools
-    compiler: musl-gcc
-    language: c
-    env:
-    - CONF_OPTIONS="--disable-parallel-mark --enable-gc-assertions"
-  - compiler: clang
-    dist: xenial
-    env:
-    - CFLAGS_EXTRA="-fsanitize=address -fno-common -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--enable-cplusplus --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-    - TESTS_CUSTOM_RUN=true
-  - addons:
-      apt:
-        packages:
-        - gcc-5
-        sources:
-        - ubuntu-toolchain-r-test
-    compiler: gcc-5
-    dist: xenial
-    language: c
-    env:
-    - CFLAGS_EXTRA="-fsanitize=address -O0"
-    - CONF_OPTIONS="--enable-gc-assertions"
-    - LDFLAGS="-fuse-ld=gold"
-  - os: osx
-    env:
-    - CFLAGS_EXTRA="-fsanitize=address -m32 -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--disable-shared --enable-cplusplus"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    language: c
-    env:
-    - CFLAGS_EXTRA="-fsanitize=memory -fno-omit-frame-pointer -std=gnu11"
-    - CONF_OPTIONS="--enable-static"
-    - TESTS_CUSTOM_RUN=true
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-fsanitize=undefined -fno-common -fno-omit-frame-pointer"
-    - TESTS_CUSTOM_RUN=true
-    - CONF_OPTIONS="--enable-cplusplus --enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-fsanitize=thread -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--enable-gc-assertions"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - clang-12
-    compiler: clang-12
-    dist: focal
-    language: c
-    env:
-    - CFLAGS_EXTRA="-O3 -fsanitize=thread -fno-omit-frame-pointer"
-    - CONF_OPTIONS="--enable-static"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    dist: focal
-    env:
-    - CFLAGS_EXTRA="-fsanitize=thread -D NO_INCREMENTAL -fno-omit-frame-pointer -D TEST_FORK_WITHOUT_ATFORK"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-gc-debug --enable-handle-fork=manual --enable-large-config --without-libatomic-ops"
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-fsanitize=thread -D NO_INCREMENTAL -fno-omit-frame-pointer -D NTHREADS=0"
-    - CONF_OPTIONS="--disable-parallel-mark --disable-thread-local-alloc --disable-shared --enable-gc-assertions --without-libatomic-ops"
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-O3 -march=native -D NTHREADS=10"
-    - CONF_OPTIONS="--enable-cplusplus --enable-static --enable-single-obj-compilation"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: clang
-    env:
-    - CFLAGS_EXTRA="-m32 -D _FORTIFY_SOURCE=2 -D GC_DISABLE_INCREMENTAL -std=gnu11"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-gc-debug"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CONF_OPTIONS="--enable-cplusplus --enable-gc-assertions --enable-static"
-    - CFLAGS_EXTRA="-D VERY_SMALL_CONFIG"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-multilib
-    compiler: gcc
-    env:
-    - CFLAGS_EXTRA="-m32 -O3 -std=gnu11"
-    - CONF_OPTIONS="--disable-shared --enable-static --enable-single-obj-compilation"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - addons:
-      apt:
-        packages:
-        - gcc-8
-        - gcc-8-multilib
-        - gcc-multilib
-    compiler: gcc-8
-    dist: focal
-    language: c
-    env:
-    - CFLAGS_EXTRA="-mx32 -march=native -D _FORTIFY_SOURCE=2"
-    - CONF_OPTIONS="--enable-large-config --enable-gc-assertions"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-x c++"
-    - CONF_OPTIONS="--enable-gc-assertions --enable-cplusplus --enable-gc-debug --disable-shared"
-    - MAKEFILE_TARGETS="all"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CC_FOR_CHECK=g++
-    - CONF_OPTIONS="--enable-gc-assertions"
-    - MAKEFILE_TARGETS="all"
-    - MAKEFILE_TARGETS_CHECK="check"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: gcc
-    env:
-    - CC_FOR_CHECK=g++
-    - CFLAGS_EXTRA="-std=c++20"
-    - CONF_OPTIONS="--enable-cplusplus --enable-gc-assertions --enable-gc-debug"
-    - MAKEFILE_TARGETS="clean"
-    - MAKEFILE_TARGETS_CHECK="check"
-    - NO_CLONE_LIBATOMIC_OPS=true
-  - compiler: clang
-    env:
-    - CFLAGS_EXTRA="-O3 -Wall -Wextra -Werror -x c++"
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="cords"
-  - compiler: gcc
-    env:
-    - CC_FOR_CHECK=g++
-    - CFLAGS_EXTRA="-O3 -Wall -Wextra -Werror -D TEST_MANUAL_VDB"
-    - MAKEFILE_NAME=Makefile.direct
-    - MAKEFILE_TARGETS="cords"
-    - MAKEFILE_TARGETS_CHECK="cord/de check"
-  - addons:
-      apt:
-        packages:
-        - g++-mingw-w64
-        - gcc-mingw-w64
-    compiler: x86_64-w64-mingw32-gcc
-    language: c
-    env:
-    - CXX=x86_64-w64-mingw32-g++
-    - CONF_OPTIONS="--host=x86_64-w64-mingw32 --enable-cplusplus --disable-shared"
-    - MAKEFILE_TARGETS="all"
-  - addons:
-      apt:
-        packages:
-        - gcc-mingw-w64
-    compiler: x86_64-w64-mingw32-gcc
-    language: c
-    env:
-    - CONF_OPTIONS="--host=x86_64-w64-mingw32 --enable-gc-assertions --enable-gc-debug --enable-threads=pthreads"
-    - MAKEFILE_TARGETS="all"
-  - addons:
-      apt:
-        packages:
-        - gcc-mingw-w64
-    compiler: i686-w64-mingw32-gcc
-    language: c
-    env:
-    - CONF_OPTIONS="--host=i686-w64-mingw32"
-    - MAKEFILE_TARGETS="all"
-    - CFLAGS_EXTRA="-fno-omit-frame-pointer"
-  - dist: focal
-    env:
-    - MAKEFILE_TARGETS="distcheck"
-    - AUTOCONF_VER=2.71
-    - AUTOMAKE_VER=1.16.5
-    - LIBTOOL_VER=2.4.7
-    - M4_VER=1.4.19
-    - NO_CLONE_LIBATOMIC_OPS=true
-
-before_install:
-- if [[ "$CPPCHECK_ENABLE" != "" ]]; then
-    CPPCHECK_VER=2.4.1;
-    git clone --depth=3 https://github.com/danmar/cppcheck.git
-            ~/cppcheck -b $CPPCHECK_VER;
-    make --directory ~/cppcheck -j8 CXXFLAGS="-O3 -march=native -D NDEBUG";
-  fi
-- if [[ "$AUTOCONF_VER" != "" || "$AUTOMAKE_VER" != ""
-        || "$LIBTOOL_VER" != "" || "$M4_VER" != "" ]]; then
-    GNUTOOLS_ROOT=`pwd`/../gnu-tools;
-    export PATH=$GNUTOOLS_ROOT/bin:$PATH;
-    GNU_DOWNLOAD_SITE=https://ftp.gnu.org/gnu;
-  fi
-- if [[ "$M4_VER" != "" ]]; then
-    M4_XZ_URL=$GNU_DOWNLOAD_SITE/m4/m4-$M4_VER.tar.xz;
-    wget -O - $M4_XZ_URL | tar xf - --xz --directory ~;
-    (cd ~/m4-$M4_VER && ./configure --prefix=$GNUTOOLS_ROOT && make -j && make install);
-  fi
-- if [[ "$LIBTOOL_VER" != "" ]]; then
-    LIBTOOL_XZ_URL=$GNU_DOWNLOAD_SITE/libtool/libtool-$LIBTOOL_VER.tar.xz;
-    wget -O - $LIBTOOL_XZ_URL | tar xf - --xz --directory ~;
-    (cd ~/libtool-$LIBTOOL_VER && ./configure --prefix=$GNUTOOLS_ROOT && make -j && make install);
-  fi
-- if [[ "$AUTOCONF_VER" != "" ]]; then
-    AUTOCONF_XZ_URL=$GNU_DOWNLOAD_SITE/autoconf/autoconf-$AUTOCONF_VER.tar.xz;
-    wget -O - $AUTOCONF_XZ_URL | tar xf - --xz --directory ~;
-    (cd ~/autoconf-$AUTOCONF_VER && ./configure --prefix=$GNUTOOLS_ROOT && make -j && make install);
-  fi
-- if [[ "$AUTOMAKE_VER" != "" ]]; then
-    AUTOMAKE_XZ_URL=$GNU_DOWNLOAD_SITE/automake/automake-$AUTOMAKE_VER.tar.xz;
-    wget -O - $AUTOMAKE_XZ_URL | tar xf - --xz --directory ~;
-    (cd ~/automake-$AUTOMAKE_VER && ./configure --prefix=$GNUTOOLS_ROOT && make -j && make install);
-  fi
-- if [[ "$MAKEFILE_TARGETS" == *"dist"* ]]; then
-    autoconf --version;
-    automake --version;
-    m4 --version;
-    libtool --version || true;
-  fi
-- if [[ "$CMAKE_OPTIONS" != "" ]]; then
-    cmake --version;
-  fi
-- if [[ "$CONF_CFLAGS" == "" ]]; then CONF_CFLAGS="-g -O2"; fi
-- if [[ "$MAKEFILE_NAME" == "" ]]; then MAKEFILE_NAME=Makefile; fi
-- if [[ "$MAKEFILE_TARGETS" == "" ]]; then MAKEFILE_TARGETS="check"; fi
-
-install:
-- if [[ "$NO_CLONE_LIBATOMIC_OPS" != true ]]; then
-    git clone --depth=50 https://github.com/ivmai/libatomic_ops.git;
-  fi
-- if [[ "$CMAKE_OPTIONS" == "" ]]; then
-    ./autogen.sh;
-  fi
-- if [[ "$GNUTOOLS_ROOT" != "" ]]; then mv $GNUTOOLS_ROOT $GNUTOOLS_ROOT-x; fi
-- if [[ "$REPORT_COVERAGE" == true ]]; then gem install coveralls-lcov; fi
-
-script:
-- if [[ "$CSA_CHECK" != true && "$CMAKE_OPTIONS" == ""
-        && "$CPPCHECK_ENABLE" == "" && "$MAKEFILE_NAME" != "Makefile.direct"
-        && "$COVERITY_SCAN_BRANCH" != 1 ]]; then
-    CFLAGS="$CONF_CFLAGS" ./configure $CONF_OPTIONS --enable-werror &&
-    cat include/config.h;
-  fi
-- if [[ "$CSA_CHECK" != true && "$CMAKE_OPTIONS" == ""
-        && "$CPPCHECK_ENABLE" == "" && "$COVERITY_SCAN_BRANCH" != 1 ]]; then
-    make -j$MAKE_NPROC -f $MAKEFILE_NAME $MAKEFILE_TARGETS
-         CFLAGS_EXTRA="$CFLAGS_EXTRA" LDFLAGS="$LDFLAGS";
-  fi
-- if [[ "$CMAKE_OPTIONS" != "" ]]; then
-    cmake $CMAKE_OPTIONS -Dbuild_tests=ON -Denable_werror=ON -Werror=dev .
-    && cmake --build . $CMAKE_BUILD_OPTIONS --parallel;
-  fi
-- if [[ "$CMAKE_OPTIONS" != "" ]]; then
-    ctest --verbose --parallel 4;
-  fi
-- if [[ "$CC_FOR_CHECK" != "" ]]; then
-    make -f $MAKEFILE_NAME $MAKEFILE_TARGETS_CHECK CC=$CC_FOR_CHECK
-            CFLAGS_EXTRA="$CFLAGS_EXTRA";
-  fi
-- if [ -f cordtest.log ]; then cat cordtest.log; fi
-- if [ -f disclaim_bench.log ]; then cat disclaim_bench.log; fi
-- if [ -f disclaimtest.log ]; then cat disclaimtest.log; fi
-- if [ -f gctest.log ]; then cat gctest.log; fi
-- if [ -f threadkeytest.log ]; then cat threadkeytest.log; fi
-- if [ -f threadleaktest.log ]; then cat threadleaktest.log; fi
-- if [ -f weakmaptest.log ]; then cat weakmaptest.log; fi
-- if [[ "$CSA_CHECK" == true ]]; then
-    set -o pipefail; ${CC} --analyze -Xanalyzer -analyzer-output=text -Werror
-        -I include -I libatomic_ops/src $CFLAGS_EXTRA
-        *.c *.cc cord/*.c cord/tests/cordtest.c cord/tests/de.c extra/gc.c
-        extra/msvc_dbg.c extra/pcr_interface.c extra/real_malloc.c
-        tests/*.c tests/*.cc tools/*.c 2>&1 | tee clang-analyzer-output.log;
-    if [ -s clang-analyzer-output.log ]; then exit 1; fi;
-  fi
-- if [[ "$CPPCHECK_ENABLE" != "" ]]; then
-    if [[ "$CPPCHECK_OUT_FILTER" == "" ]]; then CPPCHECK_OUT_FILTER="c "; fi;
-    set -o pipefail; ~/cppcheck/cppcheck --error-exitcode=2
-        -U CORD_API -U GC_API -D __SIZEOF_POINTER__=8 -D CPPCHECK
-        -I include $CPPCHECK_ENABLE |
-        grep --line-buffered "$CPPCHECK_OUT_FILTER";
-  fi
-- if [[ "$TESTS_CUSTOM_RUN" == true ]]; then
-    ASAN_OPTIONS="detect_leaks=1" UBSAN_OPTIONS="halt_on_error=1"
-        make check-without-test-driver;
-  fi
-
-after_success:
-- if [[ "$REPORT_COVERAGE" == true ]]; then
-    lcov --capture --base-directory . --directory . --output-file coverage.info;
-    lcov --remove coverage.info '/usr/*' 'cord/tests/*' 'libatomic_ops/*' 'tests/*' --output-file coverage.info;
-    lcov --list coverage.info;
-    coveralls-lcov --repo-token ${COVERALLS_TOKEN} coverage.info;
-    bash <(curl -s https://codecov.io/bash);
-  fi
-
-deploy:
-  provider: releases
-  edge: true
-  file: gc-*.tar.gz
-  file_glob: true
-  on:
-    condition: $MAKEFILE_TARGETS = distcheck
-    repo: ivmai/bdwgc
-    tags: true
diff --git a/build.zig b/build.zig
index 238847350..f7c122cc5 100644
--- a/build.zig
+++ b/build.zig
@@ -375,6 +375,11 @@ pub fn build(b: *std.Build) void {
         flags.appendSlice(&.{
             "-fvisibility=hidden",
         }) catch unreachable;
+
+        // FIXME: gctest bss is not tracked by SOFT_VDB otherise.
+        if (t.os.tag == .linux) {
+            flags.append("-D NO_VDB_FOR_STATIC_ROOTS") catch unreachable;
+        }
     } else {
         flags.append("-D GC_NOT_DLL") catch unreachable;
         if (t.os.tag == .windows) {
diff --git a/dyn_load.c b/dyn_load.c
index 4470477e0..6a895763d 100644
--- a/dyn_load.c
+++ b/dyn_load.c
@@ -1255,7 +1255,21 @@ GC_INNER void GC_register_dynamic_libraries(void)
 #else
 # include <mach-o/dyld.h>
 #endif
-#include <mach-o/getsect.h>
+
+#if CPP_WORDSZ == 64
+# define GC_MACH_HEADER mach_header_64
+#else
+# define GC_MACH_HEADER mach_header
+#endif
+
+#ifdef MISSING_MACH_O_GETSECT_H
+  EXTERN_C_BEGIN
+  extern uint8_t *getsectiondata(const struct GC_MACH_HEADER *,
+                    const char *seg, const char *sect, unsigned long *psz);
+  EXTERN_C_END
+#else
+# include <mach-o/getsect.h>
+#endif
 
 /*#define DARWIN_DEBUG*/
 
@@ -1295,12 +1309,6 @@ STATIC const char * const GC_dyld_bss_prefixes[] = {
 # define L2_MAX_OFILE_ALIGNMENT 15
 #endif
 
-#if CPP_WORDSZ == 64
-# define GC_MACH_HEADER mach_header_64
-#else
-# define GC_MACH_HEADER mach_header
-#endif
-
 STATIC const char *GC_dyld_name_for_hdr(const struct GC_MACH_HEADER *hdr)
 {
     unsigned long i, count = _dyld_image_count();