src/cmake/DawnCompilerExtraFlags.cmake

# Copyright 2024 The Dawn & Tint Authors
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this
#    list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its
#    contributors may be used to endorse or promote products derived from
#    this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

if (${DAWN_ENABLE_TSAN})
  add_compile_options(-stdlib=libc++)
  add_link_options(-stdlib=libc++)
endif ()

# Don't warn about C++20 only constructs, since Dawn requires C++20
if (("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang") OR
    ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "AppleClang") OR
    ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU"))
    add_compile_options(-Wno-c++20-compat)
endif()

################################################################################
# common_compile_options - sets compiler and linker options common for dawn
################################################################################
function(common_compile_options target)
  if (COMPILER_IS_LIKE_GNU)
    if (COMPILER_IS_CLANG)
      target_compile_options(${target}
        PRIVATE
          "-Wno-assume"
          "-Wno-deprecated-builtins"
          "-Wno-unknown-warning-option"
      )
    elseif (COMPILER_IS_GNU)
      if (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 16)
        target_compile_options(${target} PRIVATE "-Wno-sfinae-incomplete")
      endif ()
    endif ()
    target_compile_options(${target}
      PRIVATE
        "-fno-exceptions"
        "-Wno-switch-default"
        "-Wno-nrvo"
    )
    if (NOT DAWN_ENABLE_RTTI)
      target_compile_options(${target} PRIVATE "-fno-rtti")
    endif()
    if (${DAWN_WERROR})
      target_compile_options(${target}
        PRIVATE "-Werror")
    endif ()
  endif ()

  if (MSVC)
    target_compile_options(${target}
      PUBLIC
        "/utf-8"
        "/Zc:preprocessor" # Ask for standard-conformant preprocessor.
    )
  endif ()

  # Abseil headers can cause warnings when included that will cause failures
  # with -Werror.
  # Needs to be PUBLIC to propagate to targets that depend indirectly on abseil
  # via this target.
  if (NOT MSVC)
    get_target_property(deps ${target} LINK_LIBRARIES)
    if (deps MATCHES "absl")
      if (COMPILER_IS_CLANG)
        target_compile_options(${target}
          PRIVATE
            "-Wno-gcc-compat"
            "-Wno-unreachable-code-break"
            "-Wno-nullability-extension"
        )
      endif ()
      target_compile_options(${target} PUBLIC
        "-Wno-shadow"
      )
    endif ()
  endif ()

  if (COMPILER_IS_LIKE_GNU)
    set(SANITIZER_OPTIONS "")
    if (${DAWN_ENABLE_MSAN})
      list(APPEND SANITIZER_OPTIONS "-fsanitize=memory")
    endif ()
    if (${DAWN_ENABLE_ASAN})
      list(APPEND SANITIZER_OPTIONS "-fsanitize=address")
    endif ()
    if (${DAWN_ENABLE_TSAN})
      list(APPEND SANITIZER_OPTIONS "-fsanitize=thread")
    endif ()
    if (${DAWN_ENABLE_UBSAN})
      list(APPEND SANITIZER_OPTIONS "-fsanitize=undefined")
      # Extra non-default sanitizers. See //build/config/sanitizers/BUILD.gn for GN config.
      # - float-divide-by-zero (see https://dawn-review.googlesource.com/125380) is not used in
      #   GN, as //build assumes IEEE754. We could replace this with static_asserts on is_iec559,
      #   but it still might be useful. This should eventually removed in CMake or added in GN.
      list(APPEND SANITIZER_OPTIONS "-fsanitize=float-divide-by-zero")
      # - vptr is enabled in GN by default. Older versions of Clang seem to be buggy though, so gate
      #   this on a known-good Clang. We always explicitly enable or disable it because different
      #   versions of Clang differ on whether it's enabled by default with UBSan.
      if (COMPILER_IS_CLANG AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 19.1.7)
        list(APPEND SANITIZER_OPTIONS "-fsanitize=vptr")
      else()
        list(APPEND SANITIZER_OPTIONS "-fno-sanitize=vptr")
      endif()
    endif ()
    if (SANITIZER_OPTIONS)
      target_compile_options(${target}
        PUBLIC ${SANITIZER_OPTIONS})
      target_link_options(${target}
        PUBLIC ${SANITIZER_OPTIONS})
    endif ()
  endif ()

  option(DAWN_EMIT_COVERAGE "Emit code coverage information" OFF)
  if (DAWN_EMIT_COVERAGE)
    target_compile_definitions(${target}
      PRIVATE "DAWN_EMIT_COVERAGE")
    if (CMAKE_CXX_COMPILER_ID MATCHES "GNU")
      target_compile_options(${target}
        PRIVATE "--coverage")
      target_link_options(${target}
        PRIVATE "gcov")
    elseif (COMPILER_IS_CLANG OR COMPILER_IS_CLANG_CL)
      target_compile_options(${target}
        PRIVATE "-fprofile-instr-generate" "-fcoverage-mapping")
      target_link_options(${target}
        PRIVATE "-fprofile-instr-generate" "-fcoverage-mapping")
    else()
      message(FATAL_ERROR
        "Coverage generation not supported for the ${CMAKE_CXX_COMPILER_ID} toolchain")
    endif ()
  endif ()
endfunction()