add_subdirectory命令的执行顺序

Question

我的cmake配置中存在依赖关系问题。当我从项目的根目录开始构建时，总是会出现错误。当我禁用使用add_subdirectory(application)的LibCalcBin时，它成功地构建了library。然后，我可以构建application。

为什么cmake不首先构建library，然后按照application命令的顺序指定add_subdirectory。有没有办法解决这个问题？谢谢。

错误

Please set them or make sure they are set and tested correctly in the CMake files:
LibCalcBin
    linked by target "run" in directory ...

./CMakeList.txt (根目录)

cmake_minimum_required(VERSION 3.3)
project(DLLAbstract)

# specify where to put executable
SET(EXECUTABLE_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/bin)

# specify where to put binaries
SET(LIBRARY_OUTPUT_PATH ${PROJECT_SOURCE_DIR}/bin)

# compile and build library
add_subdirectory(library)

# compile and build application
add_subdirectory(application)

./图书馆

set(src LibCalc.cpp Calculator.cpp)

add_definitions(-DDLL_EXPORT)

add_library(LibCalc SHARED ${src})

./申请

set(Src main.cpp)

find_path(LibCalcHeader
    NAMES 
        LibCalc.hpp
    PATHS 
        ${PROJECT_SOURCE_DIR}/library
)

find_library(LibCalcBin
    NAMES 
        LibCalc
    PATHS 
        ${PROJECT_SOURCE_DIR}/bin/Debug
        ${PROJECT_SOURCE_DIR}/bin/Release
        ${PROJECT_SOURCE_DIR}/bin
)

include_directories(${LibCalcHeader})

add_executable(run ${Src})

target_link_libraries(run ${LibCalcBin})

Answer 1

find_library命令用于定位库，这些库不是项目的一部分。对于add_library命令创建的库，不需要特殊处理，您可以在target_link_libraries调用中使用目标名称：

target_link_libraries(run LibCalc)