如何使用CMake构建一个包括两个目录的可执行文件

编程问答 2022-08-16

问题描述

我需要编译一个可执行文件，包括client和common目录中的所有源文件

\root
 \client
   *.cpp
   *.h
   CMakeLists.txt
 \common
   *.cpp
   *.h

这是我当前的CMakeLists.txt 

cmake_minimum_required(VERSION 3.1.0)

project(Client)

set(common_dir ${PROJECT_SOURCE_DIR}/common)

include_directories(${common_dir})


set(CMAKE_CXX_STANDARD 17)

set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)
set(CMAKE_AUTOUIC ON)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17")

#set(CMAKE_BUILD_TYPE RELEASE)
if (CMAKE_BUILD_TYPE STREQUAL "RELEASE")
    add_deFinitions(-DQT_NO_DEBUG_OUTPUT)
endif (CMAKE_BUILD_TYPE STREQUAL "RELEASE")


if(CMAKE_VERSION VERSION_LESS "3.7.0")
    set(CMAKE_INCLUDE_CURRENT_DIR ON)
endif()

IF(WIN32)
    SET(OS_SPECIFIC_LIBS netapi32 wsock32)
ENDIF(WIN32)


find_package(Qt5 COMPONENTS Core required)
find_package(Qt5 COMPONENTS Widgets required)
find_package(Qt5 COMPONENTS Gui required)
find_package(Qt5 COMPONENTS Network required)
#find_package(Qt5 COMPONENTS sql required)
find_package(Qt5 COMPONENTS Svg required)
find_package(Qt5 COMPONENTS PrintSupport required)
find_package(Qt5WebSockets required)

file(GLOB client_src "*.h" "*.cpp" "Resources.qrc")
file(GLOB common_src "${common_dir}/*.h" "${common_dir}/*.cpp")
add_library(common_src)

add_executable(Client ${common_src} ${client_src})

target_link_libraries(Client ${common_dir} Qt5::Core Qt5::Widgets Qt5::Gui Qt5::Network Qt5::Svg Qt5::PrintSupport Qt5::WebSockets ${OS_SPECIFIC_LIBS})

但是我遇到了这个错误：

mingw32-make.exe[3]: *** No rule to make target '../common',needed by 'Client.exe'.  Stop.
mingw32-make.exe[2]: *** [CMakeFiles\Makefile2:126: CMakeFiles/Client.dir/all] Error 2
mingw32-make.exe[1]: *** [CMakeFiles\Makefile2:133: CMakeFiles/Client.dir/rule] Error 2
mingw32-make.exe: *** [Makefile:150: Client] Error 2

解决方法

任何一个

删除 add_library（common_src）

或

add_library(MyLib ${common_src})
add_executable(Client ${client_src])
target_link_libraries(Client MyLib)
,

似乎您在cmake中混淆了很多东西。在这里，您可以查看源（globbing is bad,don't do it）：

src/app

然后您使用file(GLOB client_src "*.h" "*.cpp" "Resources.qrc") file(GLOB common_src "${common_dir}/*.h" "${common_dir}/*.cpp") 创建一个库：

common_src

然后使用两者 add_library(common_src) 和client_src创建可执行文件：

common_src

然后尝试将add_executable(Client ${common_src} ${client_src}) 与Client链接。最后一步没有意义，因为common_dir中已经包含Client，并且不需要将common_src库链接到它。

因此，您可以简化cmake并执行以下操作（仅显示相关部分）：

common_dir

旁注：

这两个基本都做同样的事情：

#...
file(GLOB client_src "*.h" "*.cpp" "Resources.qrc")
file(GLOB common_src "${common_dir}/*.h" "${common_dir}/*.cpp")
# add_library(common_src) # Remove this line

add_executable(Client ${common_src} ${client_src}) # create Client out of common and client src

target_link_libraries(Client Qt5::Core Qt5::Widgets Qt5::Gui Qt5::Network Qt5::Svg Qt5::PrintSupport Qt5::WebSockets ${OS_SPECIFIC_LIBS})

我建议使用set(CMAKE_CXX_STANDARD 17) set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17") # remove this 代替上面的内容来设置C ++标准：

set_target_properties
c++cmakecompiler-errorslinker-errors