Question

我有个大项目。在根目录中，我创建了文件CMake\optionalsource.cmake（在目录CMake中是其他帮助程序文件），其中包含以下函数定义：

cmake_minimum_required(VERSION 3.5)
# cmake_parse_arguments needs cmake 3.5

##
# This function always adds sources to target, but when "WHEN" condition is not meet
# source is excluded from build process.
# This doesn't break build, but source is always visible for the project, what is 
# very handy when working with muti-platform project with sources needed
# only for specific platform
#
# Usage:
#      target_optional_sources(WHEN <condition> 
#                              TARGET <target>
#                              <INTERFACE|PUBLIC|PRIVATE> [items2...]
#                              [<INTERFACE|PUBLIC|PRIVATE> [items2...] ...])
##
function(target_optional_sources)
    set(options OPTIONAL "")
    set(oneValueArgs WHEN TARGET)
    set(multiValueArgs PUBLIC PRIVATE INTERFACE)

    cmake_parse_arguments(target_optional_sources 
                          "${options}" "${oneValueArgs}" "${multiValueArgs}"
                          ${ARGN})

    # for debugging purposes 
    message("TARGET ${target_optional_sources_TARGET}")
    message("PUBLIC ${target_optional_sources_PUBLIC}")
    message("PRIVATE ${target_optional_sources_PRIVATE}")
    message("INTERFACE ${target_optional_sources_INTERFACE}")
    message("WHEN ${target_optional_sources_WHEN} ${${target_optional_sources_WHEN}}")

    target_sources(${target_optional_sources_TARGET}
                   PUBLIC ${target_optional_sources_PUBLIC}
                   PRIVATE ${target_optional_sources_PRIVATE}
                   INTERFACE ${target_optional_sources_INTERFACE})

    if (NOT ${target_optional_sources_WHEN})

        set_source_files_properties(${target_optional_sources_PUBLIC}
                                    PROPERTIES HEADER_FILE_ONLY TRUE)
        set_source_files_properties(${target_optional_sources_PRIVATE}
                                    PROPERTIES HEADER_FILE_ONLY TRUE)
        set_source_files_properties(${target_optional_sources_INTERFACE}
                                    PROPERTIES HEADER_FILE_ONLY TRUE)

    endif(NOT ${target_optional_sources_WHEN})

endfunction(target_optional_sources)

这包含在根CMakeLists.txt中。现在这个功能很简单。它是受this nice SO answer和this feature request for CMake激励的。

现在我遇到了一些奇怪的问题。我的项目包含许多目标（libs / dlls / execs），我在这样的一个地方使用了此功能：

add_library(CommonLibrary STATIC
    <list of mutliplatform sources>
)  

message("=== function CommonLibrary ===")
target_optional_sources(WHEN APPLE 
                        TARGET  CommonLibrary
                        PUBLIC
                                macos/CFUtils.cpp
                                macos/CFUtils.h
                                MacMachineData.mm
                                MacMachineData.h
                                macos/MacAutoreleasePool.mm
                                macos/MacAutoreleasePool.h
                        )

在日志中，我可以看到：

1>=== function CommonLibrary ===
1>TARGET CommonLibrary
1>PUBLIC macos/CFUtils.cpp;macos/CFUtils.h;MacMachineData.mm;MacMachineData.h;macos/MacAutoreleasePool.mm;macos/MacAutoreleasePool.h
1>PRIVATE
1>INTERFACE
1>WHEN APPLE

但是下面我会看到以下错误消息：

1>CMake Error at SomeOtherLib1/CMakeLists.txt:34 (add_executable):
1>  Cannot find source file:
1>
1>    macos/CFUtils.cpp
1>
1>  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm
1>  .hpp .hxx .in .txx
1>
1>
1>CMake Error at SomeOtherLib2/CMakeLists.txt:11 (add_executable):
1>  Cannot find source file:
1>
1>    macos/CFUtils.cpp
1>
1>  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm
1>  .hpp .hxx .in .txx
1>
1>
1>CMake Error at UnitTests/CMakeLists.txt:11 (add_executable):
1>  Cannot find source file:
1>
1>    macos/CFUtils.cpp
1>
1>  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm
1>  .hpp .hxx .in .txx
1>

macos/CFUtils.cpp仅通过调用我的自定义函数来添加，那么其他CMakeLists.txt文件如何可能受到成功的函数调用的影响？当我在函数调用中对文件重新排序时，错误消息将跟随此更改。

在Visual Studio下更奇怪的是，这些错误导致错误报告，但是项目文件已成功重新生成，并且一切正常。我不能忍受它，因为它会在Jenkins机器上导致构建问题。

编辑：

这是CommonLibrary与其他目标链接的方式，例如：

add_executable(TestApp
    <Test app sources>
)

target_link_libraries(TestApp
    PRIVATE
        fmt::fmt-header-only
        CommonLibrary
        SomeOtherLibrary
)

调用自定义功能时，CMake和异常行为

0 个答案: