文件夹结构

Question

首先，我是CMake的新手。

文件夹结构

root_project
  |─── CMakeLists.txt
  |─── build
  |─── Project 1
  |      |─── build
  |      |      |─── Debug
  |      |      └─── Release
  |      |─── CMakeLists.txt
  |      |─── source
  |      |      └─── include
  |      |─── resource
  |      └─── header
  └─── Project 2
         |─── build
         |      |─── Debug
         |      └─── Release
         |─── source
         |      |─── CMakeLists.txt
         |      └─── include
         |─── resource
         └─── header

CMake文件

root_project的CMakeLists.txt：

# Specify the minimum version for CMake
cmake_minimum_required(VERSION 3.8.2 FATAL_ERROR)

# Project's name
project("RootProject X")

IF(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR})
    message(FATAL_ERROR "In-source builds not allowed. Please make a new directory (called a build directory) and run CMake from there. You may need to remove CMakeCache.txt.")
ENDIF()

OPTION(BUILD_TESTS "Decides whether the unit tests will be built." ON)

# C/C++ languages required.
enable_language(C)
enable_language(CXX)

set(CMAKE_C_STANDARD 11)
set(CMAKE_C_STANDARD_REQUIRED ON)
set(CMAKE_C_EXTENSIONS OFF)

set(CMAKE_CXX_STANDARD 14)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

# Only allow 64bit architecture
IF(CMAKE_SIZEOF_VOID_P EQUAL 8)
    # 64bit
    message(STATUS "Compiling for x86-64 platform. Proceeding...")
ELSEIF(CMAKE_SIZEOF_VOID_P EQUAL 4)
    # 32bit
    message(FATAL_ERROR "Compiling for x86 platform. This is not supported. Aborting...")
ELSE()
    # unidentified architecture
    message(FATAL_ERROR "Running on unidentified architecture. This is not supported. Aborting...")
ENDIF()

# Abort when OpenGL is not found
FIND_PACKAGE(OpenGL 4.5 REQUIRED)

IF(NOT VULKAN_FOUND)
    message(WARNING "Could not find Vulkan library.")
ENDIF()

# Add the modules
add_subdirectory("Project 1")
add_subdirectory("Project 2")

项目1的CMakeLists：

# Specify the minimum version for CMake
cmake_minimum_required(VERSION 3.8.2 FATAL_ERROR)

project("Project 1")

# Set the version number of the project here
set(VERSION_MAJOR "0")
set(VERSION_MINOR "1")
set(VERSION_PATCH "0")
set(VERSION ${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCH})

find_package(OpenGL 4.5 REQUIRED)

include_directories(${OPENGL_INCLUDE_DIR})
include_directories(${CMAKE_CURRENT_SOURCE_DIR}/sources/third-party-include/)
link_libraries(${OPENGL_gl_LIBRARY})
add_definitions(${OpenGL_DEFINITIONS})

#include_directories(${CMAKE_CURRENT_SOURCE_DIR}/sources/include/)

# ToDo: Testing
set(HEADERS
    ${CMAKE_CURRENT_SOURCE_DIR}/sources/include/Engine.h
)

set(SOURCES
    ${CMAKE_CURRENT_SOURCE_DIR}/source/Engine.cpp
)

source_group(headers FILES ${HEADERS})
source_group(sources FILES ${SOURCES})

if(WIN32)
# currently add_executable for testing purpose
add_executable("Project 1" WIN32
    #${HEADERS}
    ${SOURCES}
)
ELSEIF(UNIX AND NOT APPLE)
add_library("Project 1"
    ${HEADERS}
    ${SOURCES}
)
ELSE()
# The system is not supported
message(FATAL_ERROR "System not supported.")
ENDIF()

target_link_libraries(DarkEngine ${OPENGL_gl_LIBRARY})

项目2的CMakeLists：

# Specify the minimum version for CMake
cmake_minimum_required(VERSION 3.8.2 FATAL_ERROR)

project("Project 2")

# Set the version number of the project here
set(VERSION_MAJOR "0")
set(VERSION_MINOR "1")
set(VERSION_PATCH "0")
set(VERSION ${VERSION_MAJOR}.${VERSION_MINOR}.${VERSION_PATCH})

set(HEADERS

)

set(SOURCES

)

source_group(headers FILES ${HEADERS})
source_group(sources FILES ${SOURCES})

add_executable("Project 2" WIN32
    ${HEADERS}
    ${SOURCES}
)

target_link_libraries("Project 2" "Project 1")

问题/问题

注意：我正在尝试实现 out-of-source build ，其中Project 1是从Project 2使用的Engine。

我在root_project的构建下运行的命令：cmake .. -G "Visual Studio 15 2017 Win64"

项目2不与项目1链接
项目2并未出现在VS 2017
项目1的/ include下的我自己的头文件将显示在VS 2017中的外部依赖项而不是源

Answer 1

将我的评论转化为答案

您只需指定Project 2目标的来源。

我试过给你一个例子，CMake给你一个配置错误（这可能就是为什么它不会显示/没有重写解决方案/项目文件，如果你添加了第二个项目）：

CMake Error at CMakeLists.txt:23 (add_executable):
   add_executable called with incorrect number of arguments, no sources provided

是的，如果你添加例如您将获得的src/main.cpp到SOURCES尚不存在：

CMake Error at CMakeLists.txt:23 (add_executable):
  Cannot find source file:

    src/main.cpp

  Tried extensions .c .C .c++ .cc .cpp .cxx .m .M .mm .h .hh .h++ .hm .hpp .hxx .in .txx

因此，CMake中的工作流始终首先创建源文件，然后添加到CMakeLists.txt。使用像VS这样的IDE，您可以在项目中添加一个新项目（就像您对非生成项目所做的那样），然后将其添加到CMakeLists.txt文件中。

对于我的一些项目，我创建了一个check_and_create_source()函数，称为覆盖add_executable()次调用，但使用它已有几年了，我现在可以说这种方法没有任何实际好处。您仍然需要运行ZERO_CHECK构建来获取创建的空文件/在开始之前（当您错误输入现有源文件的包含时，您会感到困惑。）

我个人不喜欢这种全球化的选择（见Why is cmake file GLOB evil?和CMake/Ninja attempting to compile deleted `.cpp` file）

在Visual Studio下CMake构建问题

文件夹结构

CMake文件

问题/问题

1 个答案: