I am building a simple template for C/C++ CMake projects. Basically, following cmake.org own tutorial. I deviated a bit from the tutorial, and I don't know if I am doing something wrong.
So, this is the directory structure:
template
+--- CMakeLists.txt
+--- build/
| +--- default/
+--- include/
+--- myLibrary/
| +--- CMakeLists.txt
| +--- include/
| | +--- mylibrary.h
| +--- src/
| +--- myfunction.cpp
+--- src/
+--- mymain.cpp
This is template/CMakeLists.txt
project(MyProjectName VERSION 1.0)
add_subdirectory(myLibrary)
add_executable(myexecutable src/mymain.cpp)
target_link_libraries(myexecutable PUBLIC MyFunctions)
target_include_directories(myexecutable PUBLIC "${PROJECT_BINARY_DIR}")
This is template/myLibrary/CMakeLists.txt
add_library(MyFunctions src/myfunction.cpp)
target_include_directories(MyFunctions INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/include")
Now, for this to work, my library program (template/myLibrary/src/myfunction.cpp) has to include its header file like this:
#include "../include/mylibrary.h"
Which I find weird, because I am already declaring the include directory of "my Library". I mean this line in template/myLibrary/CMakeLists.txt:
target_include_directories(MyFunctions INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/include")
I was expecting to be able to include the library header file more directly(?), like this:
#include "mylibrary.h"
Is that the way it is suppossed to work? or am I missing something?
If I don't include the header like (myfunction.cpp) #include "../include/mylibrary.h".
Or, I don't declare the include directory (myLibrary/CMakeLists.txt) target_include_directories(MyFunctions INTERFACE "${CMAKE_CURRENT_SOURCE_DIR}/include"). The compilation fails:
../../src/mymain.cpp:9:12: fatal error: 'mylibrary.h' file not found
# include "mylibrary.h"
Thanks in advance for the help.
INTERFACE puts dir only in INTERFACE_INCLUDE_DIRECTORIES, while PUBLIC puts dir both in INTERFACE_INCLUDE_DIRECTORIES and in INCLUDE_DIRECTORIES. So you need use PUBLIC
target_include_directories(MyFunctions PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include")
Related
I am trying to build the netCDF C++ library as a dependency to my project on Windows 10 using MSVC shipped with VS2017 (I think v141 but not sure). Since some of the dependencies I will mention below require CMake > 3.12 I am forced to use CMake that is not shipped with VS2017. The problem is that netCDF C++ requires the netCDF C library (I guess the former is a wrapper for the latter), which in terms depends on the HDF5 library.
All can be found on github as CMake projects:
https://github.com/HDFGroup/hdf5
https://github.com/Unidata/netcdf-c
https://github.com/Unidata/netcdf-cxx4
Currently my project's structure is as follows:
MAIN PROJECT
|
*--- CMakeLists.txt
|
*--- examples (CMake subproject)
| |
| *---CMakeLists.txt
| |
| *--- example1 (CMake subproject, uses my_library)
| |
| *--- example2 (CMake subproject, uses my_library)
|
*--- deps (CMake subproject)
| |
| *--- CMakeLists.txt
| |
| *--- jsoncpp (CMake subproject, git clone)
| |
| *--- ...
| |
| *--- hdf5 (CMake subproject, git clone)
| |
| *--- netcdf-c (CMake subproject, git clone)
| |
| *--- netcdf-cxx4 (CMake subproject, git clone)
|
*--- my_library (CMake subproject, my own library that uses deps)
|
*--- my_binary (CMake subproject, my own executable that uses my_library and deps)
Until I started tinkering with netCDF I didn't have any issues. My deps CMakeLists.txt look like this:
add_subdirectory(sqlite3)
set(JSONCPP_WITH_EXAMPLE OFF CACHE BOOL "Compile JsonCpp example")
set(JSONCPP_WITH_TESTS OFF CACHE BOOL "Compile and (for jsoncpp_check) run JsonCpp test executables")
set(JSONCPP_WITH_POST_BUILD_UNITTEST OFF CACHE BOOL "Automatically run unit-tests as a post build step")
set(BUILD_STATIC_LIBS ON CACHE BOOL "Build jsoncpp_lib as a static library.")
set(BUILD_SHARED_LIBS OFF CACHE BOOL "Build jsoncpp_lib as a shared library.")
add_subdirectory(jsoncpp)
set(BUILD_SHARED_LIBS OFF CACHE BOOL "Build shared libraries")
set(BUILD_CURL_EXE OFF CACHE BOOL "Build curl EXE")
add_definitions("-DCURL_STATICLIB")
if(WIN32)
set(ENABLE_UNICODE OFF CACHE BOOL "Set to ON to use the Unicode version of the Windows API functions")
endif()
add_subdirectory(curl)
add_subdirectory(hdf5)
add_subdirectory(netcdf-c) # ISSUE with find_package and hdf5
add_subdirectory(netcdf-cxx4)
The netcdf-c subproject has the following lines, which cause a problem for me:
IF(MSVC)
SET(SEARCH_PACKAGE_NAME ${HDF5_PACKAGE_NAME})
FIND_PACKAGE(HDF5 NAMES ${SEARCH_PACKAGE_NAME} COMPONENTS C HL CONFIG REQUIRED ${NC_HDF5_LINK_TYPE})
ELSE(MSVC)
FIND_PACKAGE(HDF5 COMPONENTS C HL REQUIRED)
ENDIF(MSVC)
From what I saw the same applies to netcdf-cxx4 so solving this can hopefully be applied to it too.
I do not want to touch anything inside the respective dependenies' folders (I plan on adding those as git submodules later on). Is there a way to instruct the underlying sub-project (just like a did for e.g. JSON++) where to look without installing anything from the project one level up? Possibly a useful note here is that I also don't have any install() calls.
I'm new with cmake and try to create a small project which needs some 3rd-party libs. I would like to have the libs as git repos to always be up-to-date. Some libs are just .cpp and .hpp files (glad, imgui) and others are cmake projects (glfw, glm).
The idea is to have a 3rd-party project with all the libs as a kind of subprojects and a sandbox project which uses the libs and includes etc.
And I would like to use modern cmake code which is not installing something outside the framework structure.
Folder structure:
Framework
|--3rd_party
| |--glad
| | |--include
| | |--src
| |--glfw-master
| | |--...
| | |--CMakeLists.txt
| |--glm-master
| | |--..
| | |--CMakeLists.txt
| |--imgui-master
| | |--*.cpp
| | |--*.hpp
| | |--examples
| | | |--*.cpp
| | | |--*.hpp
| |--CMakeLists.txt
|--sandbox
| |--main.cpp
| |--CMakeLists.txt
|--CMakeLists.txt
So I created this folder structure and also some CMakeLists:
CMakeLists.txt (Framework)
cmake_minimum_required(VERSION 3.10)
project(Framework)
add_subdirectory("3rd_party")
add_subdirectory("sandbox")
CMakeLists.txt (3rd_party)
#GLFW
set(GLFW_BUILD_DOCS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_TESTS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
add_subdirectory(glfw-master)
# GLM
set(GLM_TEST_ENABLE OFF CACHE BOOL "" FORCE)
add_subdirectory(glm-master)
# Glad
add_library(
Glad STATIC
"glad/src/glad.c"
)
target_include_directories(Glad PUBLIC "glad/include")
# ImGui
add_compile_definitions(IMGUI_IMPL_OPENGL_LOADER_GLAD=1)
set(IMGUI_SOURCES
"imgui-master/imgui.cpp"
"imgui-master/imgui_demo.cpp"
"imgui-master/imgui_draw.cpp"
"imgui-master/imgui_widgets.cpp"
"imgui-master/examples/imgui_impl_glfw.cpp"
"imgui-master/examples/imgui_impl_opengl3.cpp"
)
set(IMGUI_HEADERS
"imgui-master/imconfig.h"
"imgui-master/imgui.h"
"imgui-master/imgui_internal.h"
"imgui-master/imstb_rectpack.h"
"imgui-master/imstb_textedit.h"
"imgui-master/imstb_truetype.h"
"imgui-master/examples/imgui_impl_glfw.h"
"imgui-master/examples/imgui_impl_opengl3.h"
)
add_library(
ImGui STATIC
${IMGUI_SOURCES}
${IMGUI_HEADERS}
)
target_include_directories(ImGui PUBLIC "imgui-master" "glfw-master/include" "glad/include")
CMakeLists.txt (sandbox)
project(Sandbox)
find_package(OpenGL REQUIRED)
add_executable(sandbox main.cpp)
# OpenGL
target_include_directories(Sandbox PUBLIC ${OPENGL_INCLUDE_DIR})
target_include_directories(Sandbox PUBLIC external)
# Glfw
target_include_directories(Sandbox PUBLIC "../3rd_party/glfw-master/include")
# Link libs
target_link_libraries(Sandbox PUBLIC
${OPENGL_LIBRARIES}
"../3rd_party/glfw-master/src/Debug/glfw3"
Glad
ImGui
glm_static
)
The code works but not as I expect. At first I know it's a little bit ugly maybe there is a better way to handle the path for includes and sources but the bigger problem is project structure.
For example, when I build it for ms vs studio I have three solutions
./framework.sln
./sandbox/sandbox.sln
./3rd_party/glfw-master/glfw.sln
And glad, glm and imgui are part of sandbox.sln
What I would like to have is a solution with two sub-solutions sandbox and 3rd_party which also has sub-solutions or projects for all the libs.
So is it possible at all and if yes how can I create such a structure with cmake?
After further investigation and a lot of try and error with CMake, I guess I started with wrong expectations and some missunderstandings.
It is not possible to get a useful solution/project structure for Visual Studio from CMake files because all CMake-projects will result in a VS-solution and all add_library or add_executable will be a VS-project. If I want to create a CMake-project for my framework and add GLFW as third party, which also creates a CMake-project, it will end with two different VS-solutions and bang the structure is gone. I think that is why Microsoft introduced a special open context for CMake files in Visual Studio.
If a project is opened with this context, the "solution" viewer shows the folder structure of the project. And that is more or less what I expected in the beginning.
There is also an option to switch the view to see all CMake targets (exec, libs, ...).
I also "upgraded" my CMakeLists. I use different ways to add the third party libs:
add_subdirectory for libs with CMakeLists like GLFW
add_library and INTERFACE for header-only libs like glm
add_library STATIC for static libs like ImGui (in my case)
The includes for Sandbox are provided by the public interface of the libs and the build/dependency order is given by order in target_link_libraries.
I hope that is was helpul and will spare you a lot of time ;)
Cheers!
boss0r
CMakeLists.txt (Framework)
cmake_minimum_required(VERSION 3.10)
project(OpenGL_Framework
VERSION 0.0.1
LANGUAGES CXX C # C for GLFW
)
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)
add_subdirectory(ThirdParty)
add_subdirectory(Sandbox)
CMakeLists.txt (3rd_party)
# GLFW
set(GLFW_LIB_NAME "GLFW")
set(GLFW_INC_PATH ${GLFW_LIB_NAME}/include)
set(GLFW_BUILD_DOCS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_TESTS OFF CACHE BOOL "" FORCE)
set(GLFW_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
#set(GLFW_VULKAN_STATIC OFF CACHE BOOL "" FORCE) # OFF by default
#set(BUILD_SHARED_LIBS OFF CACHE BOOL "" FORCE) # OFF by default
set(GLFW_INSTALL OFF CACHE BOOL "" FORCE)
add_subdirectory(${GLFW_LIB_NAME})
# spdlog
set(SPDLOG_LIB_NAME "spdlog")
set(SPDLOG_MASTER_PROJECT OFF CACHE BOOL "" FORCE)
add_subdirectory(${SPDLOG_LIB_NAME})
# OR
#set(SPDLOG_LIB_NAME "spdlog")
#set(SPDLOG_SRC_PATH ${SPDLOG_LIB_NAME}/src)
#set(SPDLOG_INC_PATH ${SPDLOG_LIB_NAME}/include)
#add_library(${SPDLOG_LIB_NAME}
# STATIC
# ${SPDLOG_SRC_PATH}/spdlog.cpp
#)
#target_include_directories(${SPDLOG_LIB_NAME}
# PUBLIC
# ${SPDLOG_INC_PATH})
# glm
set(GLM_LIB_NAME "glm")
set(GLM_INC_PATH ${GLM_LIB_NAME}/glm)
add_library(${GLM_LIB_NAME} INTERFACE)
target_include_directories(${GLM_LIB_NAME}
INTERFACE
${GLM_INC_PATH}
)
# OR
#set(GLM_LIB_NAME "glm")
#set(GLM_INC_PATH ${GLM_LIB_NAME}/glm)
#set(GLM_TEST_ENABLE OFF CACHE BOOL "" FORCE)
#add_subdirectory(${GLM_LIB_NAME})
#target_include_directories(${GLM_LIB_NAME}
# PUBLIC
# $(GLM_INC_PATH)
#)
# Glad
set(GLAD_LIB_NAME "Glad")
set(GLAD_SRC_PATH "${GLAD_LIB_NAME}/src")
set(GLAD_INC_PATH "${GLAD_LIB_NAME}/include")
add_library( ${GLAD_LIB_NAME}
STATIC
"${GLAD_SRC_PATH}/glad.c"
)
target_include_directories(${GLAD_LIB_NAME}
PUBLIC
"${GLAD_INC_PATH}"
)
# ImGui
set(IMGUI_LIB_NAME "ImGui")
set(IMGUI_SOURCES
"${IMGUI_LIB_NAME}/imgui.cpp"
"${IMGUI_LIB_NAME}/imgui_demo.cpp"
"${IMGUI_LIB_NAME}/imgui_draw.cpp"
"${IMGUI_LIB_NAME}/imgui_widgets.cpp"
"${IMGUI_LIB_NAME}/examples/imgui_impl_glfw.cpp"
"${IMGUI_LIB_NAME}/examples/imgui_impl_opengl3.cpp"
)
set(IMGUI_HEADERS
"${IMGUI_LIB_NAME}/imconfig.h"
"${IMGUI_LIB_NAME}/imgui.h"
"${IMGUI_LIB_NAME}/imgui_internal.h"
"${IMGUI_LIB_NAME}/imstb_rectpack.h"
"${IMGUI_LIB_NAME}/imstb_textedit.h"
"${IMGUI_LIB_NAME}/imstb_truetype.h"
"${IMGUI_LIB_NAME}/examples/imgui_impl_glfw.h"
"${IMGUI_LIB_NAME}/examples/imgui_impl_opengl3.h"
)
set(IMGUI_INC_PATH "${IMGUI_LIB_NAME}/")
add_library(${IMGUI_LIB_NAME}
STATIC
${IMGUI_SOURCES}
${IMGUI_HEADERS}
)
target_compile_definitions(${IMGUI_LIB_NAME}
PRIVATE
IMGUI_IMPL_OPENGL_LOADER_GLAD=1
)
target_include_directories(${IMGUI_LIB_NAME}
PUBLIC
"${IMGUI_INC_PATH}"
"${GLFW_INC_PATH}"
"${GLAD_INC_PATH}"
)
CMakeLists.txt (sandbox)
project(Sandbox)
find_package(OpenGL REQUIRED)
add_executable(${PROJECT_NAME} Sandbox.cpp)
target_include_directories(${PROJECT_NAME}
PUBLIC
external
${OPENGL_INCLUDE_DIR}
)
target_link_libraries(${PROJECT_NAME}
PUBLIC
${OPENGL_gl_LIBRARY}
glfw
Glad
ImGui
glm
#glm_static # if build with add_subdirectory
spdlog::spdlog
)
I've search the internet all over, but there is no simple answer for the issue.
I've read this: CMake: Attempted to add link library to target which is not built in this directory
But i don't want to put the target_link_libraries into the same cmake list, instead i want to leave the linkage commands inside each respective list because a library cmake list has to know which one library dependency it must be linked with.
Mine project's structure is this:
<main_exe> : /main
| : |
<main_lib> : +- /_3dparty
/ \ : | |
<lib_A> <lib_B> : | +- /lib_A/CMakeLists.txt
\ / : | +- /lib_B/CMakeLists.txt
<lib_X> : | +- /lib_X/CMakeLists.txt
: |
: +- /CMakeLists.txt
All 3 libraries are standalone and static, and i don't want to make them as a subdirectory to each other.
But when i tried to add_subdirectory with external binary directory from lib_A and lib_B respectively:
if (NOT TARGET lib_X)
add_subdirectory(${lib_X_ROOT} ${CMAKE_BUILD_ROOT}/_3dparty/lib_X)
endif()
add_dependencies(${PROJECT_NAME} lib_X)
target_link_libraries(${PROJECT_NAME}
PUBLIC
lib_X
)
, then the cmake throw an error:
Attempt to add link library "lib_X" to target "lib_B" which is not built in
this directory
Is there a way to put it to work w/o excessive ExternalProject_Add usage?
EDIT:
I reproduced the issue on the minimal example.
The library libB actually had slightly different structure:
/main
|
+- /_3dparty
| |
| +- /lib_A/CMakeLists.txt
| +- /lib_B
| | |
| | +- /libsubdir/CMakeLists.txt
| | +- /CMakeLists.txt
| |
| +- /lib_X/CMakeLists.txt
|
+- /CMakeLists.txt
That was the cause of the issue.
/CMakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(main_project)
set(CMAKE_BUILD_ROOT ${CMAKE_CURRENT_LIST_DIR}/_build)
set(CMAKE_LIBS_ROOT ${CMAKE_CURRENT_LIST_DIR}/_3dparty)
add_library(mainlib ${CMAKE_CURRENT_LIST_DIR}/main.cpp)
add_subdirectory(${CMAKE_LIBS_ROOT}/libA ${CMAKE_BUILD_ROOT}/_3party/libA)
add_subdirectory(${CMAKE_LIBS_ROOT}/libB ${CMAKE_BUILD_ROOT}/_3party/libB)
target_link_libraries(mainlib
PUBLIC
libA
libB
)
/_3dparty/libA/CMakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(libA_project)
add_library(libA STATIC ${CMAKE_CURRENT_LIST_DIR}/main.cpp)
add_subdirectory(${CMAKE_LIBS_ROOT}/libX ${CMAKE_BUILD_ROOT}/_3party/libX)
target_link_libraries(libA
PUBLIC
libX
)
/_3dparty/libB/CMakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(libB_project)
#add_library(libB STATIC ${CMAKE_CURRENT_LIST_DIR}/libsubdir/main.cpp)
add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/libsubdir) # the root cause of the issue
#add_subdirectory(${CMAKE_LIBS_ROOT}/libX ${CMAKE_BUILD_ROOT}/_3party/libX) # would be an error if add this twice
target_link_libraries(libB # <- the issue error is here
PUBLIC
libX
)
/_3dparty/libB/libsubdir/CMakeLists.txt
add_library(libB STATIC main.cpp)
/_3dparty/libX/CMakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(libX_project)
add_library(libX STATIC ${CMAKE_CURRENT_LIST_DIR}/main.cpp)
Output:
x:\_cmake_test\_out>cmake .. -G "Visual Studio 14 2015"
CMake Error at _3dparty/libB/CMakeLists.txt:11 (target_link_libraries):
Attempt to add link library "libX" to target "libB" which is not built in
this directory.
-- Configuring incomplete, errors occurred!
See also "X:/_cmake_test/_out/CMakeFiles/CMakeOutput.log".
If uncomment the add_library(libB ... and comment add_subdirectory(${CMAKE_CURRENT_LIST_DIR}/libsubdir) then the issue disappears.
Any suggestions how to fix that w/o edit a 3dparty library?
Do not do add_subdirectory() in cmake-projects which are likely to be used as sub-directories itself.
Instead create a super-project which does all the add_subdirectory() at the same level (in the same CMakeLists.txt). The order is not important, CMake resolves the target-dependency (done via target_link_libraries()) once all CMakeLists.txt have been processed.
This is an approach I ended up using in all my projects. It has some disadvantages, for example unit-testing of each library might be difficult, but this is solvable with conditioning the tests with a variable.
I have a static library in my project, lets call it libcommon, and I am including a header file from this library #include <libcommon/common.h>, not the angular brakets, not upper quotes. How can I configure CMakeLists.txt so that it find the include?
Assume the directory structure is like this:
-- root/
\-- src/
| |-- libcommon/common.h
| \-- main/main.c
\-- CMakeLists.txt
I tried:
include_directories (... src)
and:
include_directories (... ${main_SOURCE_DIR}/src)
but the libcommon/common.h was not found.
I figured it out while writing the question:
Instead of using just include_directories, I had to use target_include_directories:
target_include_directories(main PRIVATE src)
or:
target_include_directories(main PRIVATE ${main_SOURCE_DIR}/src)
I'm using cmake to build my project in C++. Assume I have the following directories on my Source folder
Source
|_Dir1
| |_Class.cpp
| |_Class.hpp
|
|_Dir2
|_Main.cpp
In Dir1 there's a class with its header and implementation files (Class.cpp and Class.hpp).
In Dir2 there's the main application which uses the class in Dir1
What is the good way to tell the CMakeLists in Dir2 to build the executable with Dir1/Class.cpp file?
EDIT: To be more specific, I want to define that the source file for Class.cpp has to be used in Dir1's CMakeLists.txt, and not in Dir2's. Doing it the other way feels plain wrong to me and it's hard to use, so if there's a reason they're enforcing me to do this some clarification on the topic would be nice.
What I'm currently doing is hard-coding the Class.cpp file location in Dir2/CMakeLists.txt but that just doesn't scale when I've got a bunch of classes interacting together.
Supposed you have a single CMakeLists.txt file at the Source directory, you'll create two variables using different file() commands
file(GLOB Dir1_Sources RELATIVE "Dir1" "*.cpp")
file(GLOB Dir2_Sources RELATIVE "Dir2" "*.cpp")
and add both sets generated by the file() commands to your target's source list:
add_executable(MyProgram ${Dir1_Sources} ${Dir2_Sources})
Alternatively you can place a CMakeLists.txt file under Dir1 and Dir2 (Main) looking as follows
Source
|
|_ CMakeLists.txt
| > project(MyProgram)
| > cmake_minimum_required(VERSION 3.8)
| > add_subdirectory("Dir1")
| > add_subdirectory("Dir2")
|
|_ Dir1
| |_ CMakeLists.txt
| > file(GLOB Sources "*.cpp")
| > add_library(Dir1 STATIC ${Sources})
|_ Dir2
|_ CMakeLists.txt
> file(GLOB Sources "*.cpp")
> add_executable(MyProgram ${Sources})
> target_link_libraries(MyProgram Dir1)
to add subdirectories as further (static) libraries linked to your main target.