new[CI]: add linux sanitizer tests

.github/scripts/build-sanitizer-tests.sh

@@ -0,0 +1,48 @@
+#!/bin/bash
+set -ex
+
+export CMAKE_C_COMPILER=/usr/bin/clang
+export CMAKE_CXX_COMPILER=/usr/bin/clang++
+BASE_CMAKE_ARGS="-DCMAKE_BUILD_TYPE=DEBUG -DCMAKE_COMPILE_WARNING_AS_ERROR=ON"
+if [[ "$(uname -s)" != "Darwin" ]]; then
+  BASE_CMAKE_ARGS+=" -DMLX_BUILD_METAL=OFF"
+fi
+
+run_test() {
+  local sanitizer_name=$1
+  local cmake_sanitizer_flag="-DUSE_${sanitizer_name}=ON"
+  echo "  Running tests with: ${sanitizer_name}"
+
+  case "$sanitizer_name" in
+    ASAN)
+      export ASAN_OPTIONS="detect_leaks=0"
+      ;;
+    UBSAN)
+      export UBSAN_OPTIONS="halt_on_error=0:print_stacktrace=1"
+      ;;
+    TSAN)
+      export TSAN_OPTIONS=""
+      ;;
+  esac
+
+  rm -rf build
+  mkdir -p build
+  pushd build > /dev/null
+
+  cmake .. ${BASE_CMAKE_ARGS} ${cmake_sanitizer_flag}
+  make -j $(nproc)
+  ./tests/tests
+
+  popd > /dev/null
+  unset ${sanitizer_name}_OPTIONS
+}
+
+sanitizer_arg=$(echo "$1" | tr '[:lower:]' '[:upper:]')
+
+if [[ "$sanitizer_arg" == "ASAN" || "$sanitizer_arg" == "UBSAN" || "$sanitizer_arg" == "TSAN" ]]; then
+  run_test "$sanitizer_arg"
+  echo "  ${sanitizer_arg} test run completed successfully."
+else
+  echo "Error: Invalid sanitizer '$1'. Please use one of: ASAN, UBSAN, TSAN."
+  exit 1
+fi

.github/workflows/build_and_test.yml

@@ -84,6 +84,39 @@ jobs:
       - uses: actions/checkout@v6
       - uses: ./.github/actions/build-docs
 
+  linux_sanitizer_build_and_test:
+    name: Linux Sanitizer Tests (${{ matrix.sanitizer }})
+    needs: check_lint
+    strategy:
+      fail-fast: false
+      matrix:
+        sanitizer: [ASAN, UBSAN]
+        # todo 12/16/2025: enable TSAN later + consider enabling ASAN for GPU backend tests.
+        # sanitizer: [ASAN, UBSAN, TSAN]
+    runs-on: ubuntu-22.04-arm
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Install Dependencies
+        run: |
+          export DEBIAN_FRONTEND=noninteractive
+          sudo apt-get update -y
+          sudo apt-get install -y \
+            build-essential \
+            libblas-dev \
+            liblapacke-dev \
+            libopenblas-dev \
+            cmake \
+            clang \
+            git
+          sudo apt-get clean
+          sudo rm -rf /var/lib/apt/lists/*
+
+      - name: Linux Build and Test with ${{ matrix.sanitizer }}
+        run: |
+          bash .github/scripts/build-sanitizer-tests.sh ${{ matrix.sanitizer }}
+
   linux_fedora_build_cpp:
     name: Linux Fedora (${{ matrix.arch }})
     needs: check_lint

CMakeLists.txt

@@ -45,6 +45,9 @@ option(MLX_METAL_JIT "Use JIT compilation for Metal kernels" OFF)
 option(MLX_USE_CCACHE "Use CCache for compilation cache when available" ON)
 option(BUILD_SHARED_LIBS "Build mlx as a shared library" OFF)
 option(USE_SYSTEM_FMT "Use system's provided fmt library" OFF)
+option(USE_ASAN "Enable AddressSanitizer (ASan)" OFF)
+option(USE_UBSAN "Enable UndefinedBehaviorSanitizer (UBSan)" OFF)
+option(USE_TSAN "Enable ThreadSanitizer (TSan)" OFF)
 
 # --------------------- Processor tests -------------------------
 message(
@@ -81,6 +84,63 @@ if(MLX_USE_CCACHE)
   endif()
 endif()
 
+if(USE_ASAN AND USE_TSAN)
+  message(
+    FATAL_ERROR
+      "AddressSanitizer (ASan) and ThreadSanitizer (TSan) are mutually exclusive and cannot be enabled at the same time."
+  )
+endif()
+
+set(SANITIZER_COMPILE_FLAGS "")
+set(SANITIZER_LINK_FLAGS "")
+
+if(USE_ASAN)
+  if(WIN32 AND MSVC)
+    list(APPEND SANITIZER_COMPILE_FLAGS /fsanitize=address)
+    list(APPEND SANITIZER_LINK_FLAGS /fsanitize=address)
+  else()
+    list(APPEND SANITIZER_COMPILE_FLAGS -fsanitize=address)
+    list(APPEND SANITIZER_LINK_FLAGS -fsanitize=address)
+    if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+      list(APPEND SANITIZER_LINK_FLAGS -lpthread)
+    endif()
+  endif()
+endif()
+
+if(USE_UBSAN)
+  if(WIN32 AND MSVC)
+    if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+      list(APPEND SANITIZER_COMPILE_FLAGS -fsanitize=undefined)
+      list(APPEND SANITIZER_LINK_FLAGS -fsanitize=undefined)
+    else()
+      message(
+        WARNING
+          "UndefinedBehaviorSanitizer (UBSan) is not directly supported via a simple flag in MSVC."
+      )
+    endif()
+  else()
+    list(APPEND SANITIZER_COMPILE_FLAGS -fsanitize=undefined)
+    list(APPEND SANITIZER_LINK_FLAGS -fsanitize=undefined)
+  endif()
+endif()
+
+if(USE_TSAN)
+  if(WIN32 AND MSVC)
+    message(
+      FATAL_ERROR
+        "ThreadSanitizer (TSan) is not supported by the MSVC compiler. Please use Clang or GCC."
+    )
+  elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+    message(FATAL_ERROR "ThreadSanitizer (TSan) is not supported on macOS.")
+  else()
+    list(APPEND SANITIZER_COMPILE_FLAGS -fsanitize=thread)
+    list(APPEND SANITIZER_LINK_FLAGS -fsanitize=thread)
+    if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+      list(APPEND SANITIZER_LINK_FLAGS -lpthread)
+    endif()
+  endif()
+endif()
+
 # ----------------------------- Lib -----------------------------
 
 include(FetchContent)
@@ -93,6 +153,8 @@ add_library(mlx)
 # ‘std::pair<float, float>’ when C++17 is enabled changed to match C++14 in GCC
 # 10.1
 target_compile_options(mlx PRIVATE -Wno-psabi)
+target_compile_options(mlx PUBLIC ${SANITIZER_COMPILE_FLAGS})
+target_link_options(mlx PUBLIC ${SANITIZER_LINK_FLAGS})
 
 if(MLX_BUILD_CUDA)
   enable_language(CUDA)

tests/CMakeLists.txt

@@ -37,5 +37,7 @@ target_sources(
           ${METAL_TEST_SOURCES})
 
 target_link_libraries(tests PRIVATE mlx doctest)
+target_compile_options(tests PRIVATE ${SANITIZER_COMPILE_FLAGS})
+target_link_options(tests PRIVATE ${SANITIZER_LINK_FLAGS})
 doctest_discover_tests(tests)
 add_test(NAME tests COMMAND tests)