警告
本文最后更新于 2024-01-15，文中内容可能已过时。
一、基本概念构建类型
CMake可以识别的构建类型是：
- Debug：用于在没有优化的情况下，使用带有调试符号构建库或者可执行文件
- Release: 用于构建的优化的库或者可执行文件，不包含调试符号
- RelWithDebInfo：用于构建较少的优化库或者可执行文件，包含调试符号
- MinSizeRel：用于不增加目标代码大小的优化方式，来构建库或者可执行文件
控制生成构建系统使用的配置变量是CMAKE_BUILD_TYPE，该变量默认为空。
这里我们仍然选择CMake第三篇—动态库和静态库的补充中的代码，但是这里我们对CMakeLists.txt稍作修改。
二、项目结构
1
2
3
4
5
6
7
8
9
10
11
12
13
14
| .
├── cmake
│ └── message_config.cmake.in
├── message-module
│ ├── CMakeLists.txt
│ ├── include
│ │ ├── message_export_lib.h
│ │ └── message.h
│ └── src
│ └── message.cpp
├── CMakeLists.txt
└── hello_world.cpp
4 directories, 9 files
|
项目源码: https://github.com/jianye0428/CMake_Learning_Notes/tree/main/Note_5/message_module_lib_standard
2.1 message-module模块下的CMakeLists.txt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
file(GLOB SOURCE_FILE ${CMAKE_CURRENT_SOURCE_DIR}/src/*.cpp)
if (BUILD_SHARED_LIBS)
add_library(test_message SHARED ${SOURCE_FILE})
target_compile_definitions(test_message PUBLIC -DMESSAGE_LIB_SHARED_BUILD)
target_compile_definitions(test_message PRIVATE -DMESSAGE_LIB_EXPORTS)
else()
add_library(test_message STATIC ${SOURCE_FILE})
endif()
# 添加别名，以便库可以在构建树中使用，例如在测试时
add_library(test_message::test_message ALIAS test_message)
target_include_directories(test_message
PUBLIC
$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>/include
$<INSTALL_INTERFACE:include>
)
set_target_properties(test_message PROPERTIES
CXX_STANDARD 11
CMAKE_CXX_STANDARD_REQUIRED True
)
set_target_properties(test_message PROPERTIES
DEBUG_POSTFIX "_debug"
RELEASE_POSTFIX "_release"
)
install(TARGETS test_message
EXPORT message_export_target
RUNTIME DESTINATION "bin"
LIBRARY DESTINATION "lib"
ARCHIVE DESTINATION "lib"
)
install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/include/
DESTINATION "include"
FILES_MATCHING PATTERN "*.h"
)
install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/include/
DESTINATION "include"
FILES_MATCHING PATTERN "*.hpp"
)
install(EXPORT message_export_target
FILE message_lib.cmake
DESTINATION lib/cmake/test_message
)
include(CMakePackageConfigHelpers)
# generate the config file that is includes the exports
configure_package_config_file(
${CMAKE_SOURCE_DIR}/cmake/message_config.cmake.in
"${CMAKE_SOURCE_DIR}/cmake/message_config.cmake"
INSTALL_DESTINATION "lib/cmake/test_message"
)
# generate the version file for the config file
write_basic_package_version_file(
"${CMAKE_SOURCE_DIR}/cmake/message_config_version.cmake"
VERSION "${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}"
COMPATIBILITY AnyNewerVersion
)
install(FILES
${CMAKE_SOURCE_DIR}/cmake/message_config.cmake
${CMAKE_SOURCE_DIR}/cmake/message_config_version.cmake
DESTINATION lib/cmake/test_message
)
export(EXPORT message_export_target FILE ${CMAKE_SOURCE_DIR}/cmake/message_config_version.cmake)
|
代码释义:
这里，我们基本上没有做修改，只添加了以下内容：
引用
1
2
3
4
| set_target_properties(test_message PROPERTIES
DEBUG_POSTFIX "_debug"
RELEASE_POSTFIX "_release"
)
|
这将在 debug 构建模式下将库名后缀设置为 _debug，在 release 构建模式下将库名后缀设置为 _release。
然后，可以使用 test_message_debug 或 test_message_release 来引用库。当然，我们其实可以使用find_package，然后直接使用库的别名test_message即可。
2.2 根目录下的CMakeLists.txt
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
cmake_minimum_required(VERSION 3.10 FATAL_ERROR)
project(hello-world LANGUAGES CXX)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
option(BUILD_SHARED_LIBS "Specifies the type of libraries (SHARED or STATIC) to build" OFF)
# Set install direcotory
if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
set(CMAKE_INSTALL_PREFIX ${CMAKE_SOURCE_DIR}/output/)
endif()
if(NOT CMAKE_BUILD_TYPE)
set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type" FORCE)
endif()
message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
message(STATUS "C flags, Debug configuration: ${CMAKE_C_FLAGS_DEBUG}")
message(STATUS "C flags, Release configuration: ${CMAKE_C_FLAGS_RELEASE}")
message(STATUS "C flags, Release configuration with Debug info: ${CMAKE_C_FLAGS_RELWITHDEBINFO}")
message(STATUS "C flags, minimal Release configuration: ${CMAKE_C_FLAGS_MINSIZEREL}")
message(STATUS "C++ flags, Debug configuration: ${CMAKE_CXX_FLAGS_DEBUG}")
message(STATUS "C++ flags, Release configuration: ${CMAKE_CXX_FLAGS_RELEASE}")
message(STATUS "C++ flags, Release configuration with Debug info: ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
message(STATUS "C++ flags, minimal Release configuration: ${CMAKE_CXX_FLAGS_MINSIZEREL}")
add_subdirectory(${CMAKE_SOURCE_DIR}/message-module)
include_directories(
${CMAKE_SOURCE_DIR}/message-module/include
)
add_executable(
${PROJECT_NAME}
${CMAKE_SOURCE_DIR}/hello_world.cpp
)
target_link_libraries(
${PROJECT_NAME}
test_message
)
|
这里，我们添加了以下内容：
引用
1
2
3
4
5
6
7
8
9
10
11
12
| if(NOT CMAKE_BUILD_TYPE)
set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type" FORCE)
endif()
message(STATUS "Build type: ${CMAKE_BUILD_TYPE}")
message(STATUS "C flags, Debug configuration: ${CMAKE_C_FLAGS_DEBUG}")
message(STATUS "C flags, Release configuration: ${CMAKE_C_FLAGS_RELEASE}")
message(STATUS "C flags, Release configuration with Debug info: ${CMAKE_C_FLAGS_RELWITHDEBINFO}")
message(STATUS "C flags, minimal Release configuration: ${CMAKE_C_FLAGS_MINSIZEREL}")
message(STATUS "C++ flags, Debug configuration: ${CMAKE_CXX_FLAGS_DEBUG}")
message(STATUS "C++ flags, Release configuration: ${CMAKE_CXX_FLAGS_RELEASE}")
message(STATUS "C++ flags, Release configuration with Debug info: ${CMAKE_CXX_FLAGS_RELWITHDEBINFO}")
message(STATUS "C++ flags, minimal Release configuration: ${CMAKE_CXX_FLAGS_MINSIZEREL}")
|
首先，检查是否设置了构建类型。如果没有，则将构建类型设置为 Release。然后，它使用 message 命令输出各种编译标志，包括 C 和 C++ 的 Debug 和 Release 配置，以及最小 Release 配置和带有调试信息的 Release配置。这些信息对于调试和优化构建非常有用。
2.3 验证输出
我们执行以下命令，这里没有指定构建类型，即默认构建类型为Release。
1
2
3
| mkdir build
cd build
cmake ..
|
输出:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
| -- The CXX compiler identification is GNU 7.5.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Build type: Release
-- C flags, Debug configuration:
-- C flags, Release configuration:
-- C flags, Release configuration with Debug info:
-- C flags, minimal Release configuration:
-- C++ flags, Debug configuration: -g
-- C++ flags, Release configuration: -O3 -DNDEBUG
-- C++ flags, Release configuration with Debug info: -O2 -g -DNDEBUG
-- C++ flags, minimal Release configuration: -Os -DNDEBUG
-- Configuring done
-- Generating done
-- Build files have been written to: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/build
|
执行make:
1
2
3
4
5
6
| [ 25%] Building CXX object message_module/CMakeFiles/test_message.dir/src/message.cpp.o
[ 50%] Linking CXX static library ../lib/libtest_message_release.a
[ 50%] Built target test_message
[ 75%] Building CXX object CMakeFiles/hello-world.dir/hello_world.cpp.o
[100%] Linking CXX executable bin/hello-world
[100%] Built target hello-world
|
可以看到，我们执行make命令后，生成的库命名为libtest_message_release.a,并将其存入lib目录中。
执行:
输出结果如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
| [ 50%] Built target test_message
[100%] Built target hello-world
Install the project...
-- Install configuration: "Release"
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/lib/libtest_message_release.a
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/include
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/include/message_export_lib.h
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/include/message.h
-- Up-to-date: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/include
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/lib/cmake/test_message/message_lib.cmake
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/lib/cmake/test_message/message_lib-release.cmake
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/lib/cmake/test_message/message_config.cmake
-- Installing: /home/jiangli/repo/tutorials/cmake-tutorial/chapter1/12/output/lib/cmake/test_message/message_config_version.cmake
|
设置构建类型为debug:
1
2
3
| mkdir build
cd build
cmake .. -DCMAKE_BUILD_TYPE=Debug
|
则输出:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
| -- The CXX compiler identification is GNU 7.5.0
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/c++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Build type: Debug
-- C flags, Debug configuration:
-- C flags, Release configuration:
-- C flags, Release configuration with Debug info:
-- C flags, minimal Release configuration:
-- C++ flags, Debug configuration: -g
-- C++ flags, Release configuration: -O3 -DNDEBUG
-- C++ flags, Release configuration with Debug info: -O2 -g -DNDEBUG
-- C++ flags, minimal Release configuration: -Os -DNDEBUG
-- Configuring done
-- Generating done
-- Build files have been written to: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/build
|
执行make:
输出如下:
1
2
3
4
5
6
| [ 25%] Building CXX object message_module/CMakeFiles/test_message.dir/src/message.cpp.o
[ 50%] Linking CXX static library ../lib/libtest_message_debug.a
[ 50%] Built target test_message
[ 75%] Building CXX object CMakeFiles/hello-world.dir/hello_world.cpp.o
[100%] Linking CXX executable bin/hello-world
[100%] Built target hello-world
|
可以看到，我们执行make命令后，生成的库命名为libtest_message_debug.a,并将其存入lib目录中。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
| Consolidate compiler generated dependencies of target test_message
[ 50%] Built target test_message
Consolidate compiler generated dependencies of target hello-world
[100%] Built target hello-world
Install the project...
-- Install configuration: "Debug"
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/lib/libtest_message_debug.a
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/include
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/include/message_export_lib.h
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/include/message.h
-- Up-to-date: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/include
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/lib/cmake/test_message/message_lib.cmake
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/lib/cmake/test_message/message_lib-debug.cmake
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/lib/cmake/test_message/message_config.cmake
-- Installing: /home/yejian/yejian_personal/c++_playground/CMake_Learning_Notes/Note_5/message_module_lib_standard/output/lib/cmake/test_message/message_config_version.cmake
|
三、补充
Release和Debug在构建项目通常很有用，如评估编译器优化级别的效果。对于单配置生成器，如Unix Makefile、MSYS Makefile或者Ninja，因为要对项目重新配置，这里需要运行CMake两次。
不过，CMake也支持符合配置生成器。这些通常是集成开发环境提供的项目文件，最显著的是Visual Studio和XCode，它们可以同时处理多个配置。可以使用CMAKE_CONFIGURATION_TYPES变量对这些生成器的可用配置进行调整。
1
2
3
| mkdir -p build
cd build
cmake .. -G"Visual Studio 14 2019 Win64" -D CMAKE_CONFIGURATION_TYPES="Release;Debug"
|
将为Release和Debug配置生成一个构建树。然后，您可以使–config标志来决定构建这两个中的哪一个:
1
| cmake --build . --config Release
|
Jian YE
支付宝
微信