如何阻止 CMake 将特定于平台的标志传递给编译器？

Question

我正在尝试交叉编译我的应用程序。我创建了一个 CMake 文件，该文件使用 Emscripten 构建我的应用程序，它按预期工作。现在我正在修改 CMake 文件以使用 MinGW 编译我的应用程序。问题是 CMake 正在传递 Windows g++ 无法识别的 MacOS 标志。

CMake 将这些选项传递给 g++（以及目标文件和源文件的路径）

-I/usr/local/include  -O3 -g -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -mmacosx-version-min=10.13   -std=gnu++1z

然后我从 g++

得到这个错误

error: unrecognized command line option ‘-mmacosx-version-min=10.13’

有没有一种简单的方法可以阻止 CMake 将 MacOS 特定选项传递给 Windows 编译器？或者 g++ 忽略这些无法识别的选项的方法？

我目前正在使用 find 和 xargs 进行编译。这只是一个临时解决方案，因为我真的很想让它工作！

我在谷歌上搜索了一段时间，似乎找不到解决方案。我尝试使用 make 但它似乎有空间问题。我最后的选择是 bash 脚本。我宁愿不使用 bash 作为构建系统！

这是我的 CMakeLists.txt 文件。 Emscripten 构建有效（定义了 EMBUILD），但 MinGW 构建无效。我尝试将 CMAKE_SYSTEM_NAME 设置为各种疯狂的值，但这似乎没有任何区别。

cmake_minimum_required(VERSION 3.10)
project(Classic_Tower_Defence)

option(EMBUILD "Build with emscripten, mingw otherwise" YES)

set(EMSCRIPTEN_CC /usr/local/Cellar/emscripten/1.37.37/libexec/emcc)
set(MINGW_CC /usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-g++)
if(EMBUILD)
    set(CC ${EMSCRIPTEN_CC})
else()
    set(CC ${MINGW_CC})
    set(CMAKE_SYSTEM_NAME Windows)
    set(CMAKE_CROSSCOMPILING YES)
endif()

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_COMPILER ${CC})
set(CMAKE_C_COMPILER ${CC})
set(RES_PATH /Users/indikernick/Library/Developer/Xcode/DerivedData/Classic_Tower_Defence-dcezwdbogljnithjukklclgyblij/Build/Products/Debug/Classic\ Tower\ Defence.app/Contents/Resources)

#if (CMAKE_BUILD_TYPE MATCHES RELEASE)
    set(EXTRA_FLAGS "-O3 --closure 1")
#else()
#    set(EXTRA_FLAGS "-s DEMANGLE_SUPPORT=1")
#endif()

if (EMBUILD)

set(LINKER_FLAGS " \
  ${EXTRA_FLAGS} \
  -s WASM=1 \
  -s USE_WEBGL2=1 \
  -s USE_SDL=2 \
  -s TOTAL_MEMORY=805306368 \
  -s DISABLE_EXCEPTION_CATCHING=0 \
  --pre-js '${PROJECT_SOURCE_DIR}/Webpage/init.js' \
  --shell-file '${PROJECT_SOURCE_DIR}/Webpage/index.html' \
  --preload-file '${RES_PATH}@/' \
")
set(CMAKE_CXX_FLAGS " \
  ${EXTRA_FLAGS} \
  -msse3 \
")

else()

# -static-libstdc++ -static-libgcc  -L./ -Wl,-rpath,./ -lopengl32 -lSDL2 -lSDL2_Mixer -lglew32 -o main.exe

set(LINKER_FLAGS " \
  -static-libstdc++ \
  -static-libgcc \
  -L../lib \
  -Wl,-rpath,./ \
  -lopengl32 \
  -lSDL2 \
  -lSDL2_Mixer \
  -lglew32 \
")
set(CMAKE_CXX_FLAGS "-O3 -DGLM_FORCE_CTOR_INIT")

endif()

include_directories(/usr/local/include/)

set(SOURCE_FILES 
        "Classic Tower Defence/Game/create spawner.cpp"
        "Classic Tower Defence/Game/unit death system.cpp"
        "Classic Tower Defence/Game/game info model.cpp"
        "Classic Tower Defence/Game/game info view.cpp"
        "Classic Tower Defence/Game/splash damage system.cpp"
        "Classic Tower Defence/Game/tower beam rendering system.cpp"
        "Classic Tower Defence/Game/aura damage system.cpp"
        "Classic Tower Defence/Game/load map.cpp"
        "Classic Tower Defence/Game/cursor systems.cpp"
        "Classic Tower Defence/Game/tower reset rof system.cpp"
        "Classic Tower Defence/Game/base damage system.cpp"
        "Classic Tower Defence/Game/unit death sound system.cpp"
        "Classic Tower Defence/Game/unit motion system.cpp"
        "Classic Tower Defence/Game/count live units.cpp"
        "Classic Tower Defence/Game/tower beam anim system.cpp"
        "Classic Tower Defence/Game/load towers.cpp"
        "Classic Tower Defence/Game/turret damage system.cpp"
        "Classic Tower Defence/Game/tower sound system.cpp"
        "Classic Tower Defence/Game/load prototype.cpp"
        "Classic Tower Defence/Game/stats controller.cpp"
        "Classic Tower Defence/Game/unit rendering system.cpp"
        "Classic Tower Defence/Game/unit death anim system.cpp"
        "Classic Tower Defence/Game/tower aura rendering system.cpp"
        "Classic Tower Defence/Game/tower aim system.cpp"
        "Classic Tower Defence/Game/unit damage system.cpp"
        "Classic Tower Defence/Game/slow effect system.cpp"
        "Classic Tower Defence/Game/game logic.cpp"
        "Classic Tower Defence/Game/next wave.cpp"
        "Classic Tower Defence/Game/unit regen system.cpp"
        "Classic Tower Defence/Game/unit effect system.cpp"
        "Classic Tower Defence/Game/poison effect system.cpp"
        "Classic Tower Defence/Game/tower rendering system.cpp"
        "Classic Tower Defence/Game/load waves.cpp"
        "Classic Tower Defence/Game/tower projectile rendering system.cpp"
        "Classic Tower Defence/Game/unit health rendering system.cpp"
        "Classic Tower Defence/Game/unit walk anim system.cpp"
        "Classic Tower Defence/Game/init map info.cpp"
        "Classic Tower Defence/Game/load level.cpp"
        "Classic Tower Defence/Game/sound queue.cpp"
        "Classic Tower Defence/Game/unit death rendering system.cpp"
        "Classic Tower Defence/Game/tower rof system.cpp"
        "Classic Tower Defence/Game/stats view.cpp"
        "Classic Tower Defence/Game/spawner timing system.cpp"
        "Classic Tower Defence/Game/load base.cpp"
        "Classic Tower Defence/Game/stats model.cpp"
        "Classic Tower Defence/Game/spawner system.cpp"
        "Classic Tower Defence/Game/preview entity.cpp"
        "Classic Tower Defence/Game/game view.cpp"
        "Classic Tower Defence/Game/create tower.cpp"
        "Classic Tower Defence/Game/ui view.cpp"
        "Classic Tower Defence/Game/get wave info.cpp"
        "Classic Tower Defence/Game/firing anim system.cpp"
        "Classic Tower Defence/Game/create level.cpp"
        "Classic Tower Defence/Game/tower range rendering system.cpp"
        "Classic Tower Defence/Game/load spawner.cpp"
        "Classic Tower Defence/Game/map rendering system.cpp"
        "Classic Tower Defence/Game/app.cpp"
        "Classic Tower Defence/main.cpp"
)

add_executable(Classic_Tower_Defence ${SOURCE_FILES})
if (EMBUILD)
    set_target_properties(Classic_Tower_Defence PROPERTIES OUTPUT_NAME index.html)
else()
    set_target_properties(Classic_Tower_Defence PROPERTIES OUTPUT_NAME main.exe)
endif()
set_target_properties(Classic_Tower_Defence PROPERTIES LINK_FLAGS "${LINKER_FLAGS}")

您可能会说我不是 CMake 专家！我应该使用生成器表达式并查找模块。我真的不知道如何处理字符串并确保在正确的位置有反斜杠和引号。但它有效（一半有效）

Answer 1

将我的评论变成答案

我已经成功地 the following minimal example - assuming from the visible paths in your code that you did install mingw 通过例如brew install mingw-w64:

编辑：同样的程序也成功地用 this OpenGL example 测试了。

$ git clone https://github.com/jameskbride/cmake-hello-world.git
Cloning into 'cmake-hello-world'...
remote: Counting objects: 56, done.
remote: Total 56 (delta 0), reused 0 (delta 0), pack-reused 56
Unpacking objects: 100% (56/56), done.

$ cd cmake-hello-world/
$ mkdir build
$ cd build

$ export CC=/usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-gcc
$ export CXX=/usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-g++ 

$ cmake -D CMAKE_SYSTEM_NAME=Windows -G "Unix Makefiles" ..
-- The C compiler identification is GNU 7.3.0
-- The CXX compiler identification is GNU 7.3.0
-- Check for working C compiler: /usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-gcc
-- Check for working C compiler: /usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-gcc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-g++
-- Check for working CXX compiler: /usr/local/Cellar/mingw-w64/5.0.3_3/toolchain-x86_64/bin/x86_64-w64-mingw32-g++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /.../cmake-hello-world/build

$ cmake --build .
Scanning dependencies of target Hello
[ 25%] Building CXX object Hello/CMakeFiles/Hello.dir/Speaker.cpp.obj
[ 50%] Linking CXX static library libHello.a
[ 50%] Built target Hello
Scanning dependencies of target CMakeHelloWorld
[ 75%] Building CXX object CMakeFiles/CMakeHelloWorld.dir/HelloWorld.cpp.obj
[100%] Linking CXX executable CMakeHelloWorld.exe
[100%] Built target CMakeHelloWorld

主要是编译器和system/platform变量必须在project()命令之前定义。还有 CMAKE_SYSTEM_NAME is the key to enable cross compiling.

正如@Tsyvarev 评论的那样，这通常在 toolchain 文件中完成（而不是 "pollute" 您的跨平台 CMake 代码）。

您的完整代码更适合在 Code Review Stack Exchange 站点上进行审查。

如何阻止 CMake 将特定于平台的标志传递给编译器？

How to stop CMake from passing platform specific flags to compiler?

c++

cross-platform

g++

cmake