Question

在我的CMake项目开始时,Im在MCMAKE_CXX_FLAGS等变量中设定了一般汇编旗帜。

set(CMAKE_CXX_FLAGS "-W -Wall ${CMAKE_CXX_FLAGS}")

稍后,我需要补充具体组合的汇编旗帜(储存在BUILD_FLAGS)。 Can 我为此使用了以下指挥:

set_target_properties(${TARGET} PROPERTIES COMPILE_FLAGS ${BUILD_FLAGS})

或者,我不得不人工添加CMAKE_CXX_FLAGS:

set_target_properties(${TARGET} PROPERTIES COMPILE_FLAGS "${CMAKE_CXX_FLAGS} ${BUILD_FLAGS}")

预防 CMAKE_CXX_FLAGS BUILD -FLAGS

Answer 1

第一种:

set_target_properties(${TARGET} PROPERTIES CompILE_FLAGS ${BUILD_FLAGS})

注册号为FLAGS的旗帜在CMAKE_CXX_FLAGS汇编TARGET来源后附。这些文件是背后的,但我只是试图确保。

CompILE_FLAGS

   Additional flags to use when compiling this target s sources. 
   
   The CompILE_FLAGS property sets additional compiler flags used to
   build sources within the target.  Use COMPILE_DEFINITIONS to
   pass additional preprocessor definitions.

整个指挥线将相当于:

${CMAKE_CXX_COMPILER} ${CMAKE_CXX_FLAGS} ${CompILE_FLAGS} -o foo.o -c foo.cc

正如Ramon所说,你总是可以检查make VERBOSE=1。

Answer 2

^{The accepted answer is still working but outdated since 2013.

This answer is based and new functions from CMake v2.8.12, v3.3 and v3.13.}

Since CMake-2.8.12 (2013)

设置<条码>CMAKE_CXX_FLAGS的两个新指挥部:

target_compile_options() (for one single target)
add_compile_options() (for all targets)

最新版本的文件自cmake-2.8.12以来没有变化:

您可以使用:

target_compile_options(${TARGET} PRIVATE ${BUILD_FLAGS})

或者简单地说,如果你有一个目标:

add_compile_options(${BUILD_FLAGS})

More examples

target_compile_options(mylib PRIVATE   -O2) # only internal
target_compile_options(mylib INTERFACE -gl) # only external
target_compile_options(mylib PUBLIC    -g)  # same as PRIVATE + INTERFACE

# multiple targets and flags
target_compile_options(mylib1 mylib2 PRIVATE -Wall -Wextra)

target_compile_options(    mylib PUBLIC -DUSEXX)  # Bad
target_compile_definitions(mylib PUBLIC -DUSEXX)  # OK

add_compile_options(-Wall -Wextra) # for all targets in current directory
add_compile_options(-DUSEXX)       # Bad
add_definitions(-DUSEXX)           # OK

Deprecated `COMPILE_FLAGS`

cmake-3.0document signsCOMPILE_FLAGS deprecated:

COMPILE_FLAGS

在汇编这一目标来源时,还要使用更多的旗帜。

The COMPILE_FLAGS property sets additional compiler flags used to build sources within the target. Use COMPILE_DEFINITIONS to pass additional preprocessor definitions.

This property is deprecated. Use the COMPILE_OPTIONS property or the target_compile_options command instead.

如果您仍然希望使用<代码>_target_properties()。您可使用<条码>。

set_target_properties(${TARGET} PROPERTIES COMPILE_OPTIONS ${BUILD_FLAGS})

Since CMake-3.3 (2015)

rel=“noreferer”>>,如在上所示。

CMake generator expression 适用于${BUILD_FLAGS}/code>:
C++ language using $<COMPILE_LANGUAGE:CXX> (can also be C, CUDA...) Clang compiler using $<CXX_COMPILER_ID:Clang> (can also be GNU for gcc, or MSVCfor Visual C++... see full list) (use $<C_COMPILER_ID:Clang> instead if language is C) and more as supported C++ feature or compiler version... (see documentation) 您可以使用: target_compile_options(${TARGET} PRIVATE $<$<COMPILE_LANGUAGE:CXX>:${BUILD_FLAGS_FOR_CXX}> $<$<COMPILE_LANGUAGE:C>:${BUILD_FLAGS_FOR_C}>) 或大约汇编者: target_compile_options(${TARGET} PRIVATE $<$<CXX_COMPILER_ID:Clang>:${BUILD_FLAGS_FOR_CLANG}> $<$<CXX_COMPILER_ID:GNU>:${BUILD_FLAGS_FOR_GCC}> $<$<CXX_COMPILER_ID:MSVC>:${BUILD_FLAGS_FOR_VISUAL}>) Since CMake-3.13 (2018) 新的职能target_link_options ( 如 Different options for C and C++ files 最好的办法是利用两个不同的目标来区分C文档和C++文档。

Since CMake-2.8.12 (2013)

More examples

Deprecated COMPILE_FLAGS

Since CMake-3.3 (2015)

Since CMake-3.13 (2018)

Different options for C and C++ files

友情链接

Deprecated `COMPILE_FLAGS`