In my CMake script I append the path to a folder containing <PackageName>Config.cmake to <PackageName>_ROOT and then call find_package(<PackageName> REQUIRED) but it can't find my package.
When I use CMAKE_FIND_DEBUG_MODE I see my folder listed in <PackageName>_ROOT CMake variable [CMAKE_FIND_USE_PACKAGE_ROOT_PATH] (it is actually the only folder there), but it is not listed after find_package considered the following locations for the Config module:.
Why am I getting such behaviour? I use CMake 3.18.1 from Android Studio. The package I'm trying to find is OpenCV.
Relatively to my CMakeLists.txt file OpenCV is installed in ../../build/opencv-build<custom suffix>, so my code for finding it is:
get_filename_component(OPENCV_BUILD_DIRS_ROOT ../../build REALPATH)
file(GLOB OPENCV_BUILD_DIRS ${OPENCV_BUILD_DIRS_ROOT}/opencv-build*)
list(APPEND OpenCV_ROOT ${OPENCV_BUILD_DIRS})
find_package(OpenCV ${OPENCV_VERSION} REQUIRED ${OPENCV_PUBLIC_LIBRARIES} ${OPENCV_PRIVATE_LIBRARIES})
When I run it on Linux (WSL actually), everything works fine and CMake finds OpenCV succesfully in ../../build/opencv-build (or <project path>/build/opencv-build in the form of absolute path).
But when I try to build the project from Android Studio it doesn't, and I get this output from CMAKE_FIND_DEBUG_MODE:
CMake Debug Log at external/opencv/CMakeLists.txt:12 (find_package):
find_package considered the following paths for OpenCV.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/cmake/3.18.1/share/cmake-3.18/Modules/FindOpenCV.cmake
The file was not found.
<PackageName>_ROOT CMake variable [CMAKE_FIND_USE_PACKAGE_ROOT_PATH].
<project path>/build/opencv-build
CMAKE_PREFIX_PATH variable [CMAKE_FIND_USE_CMAKE_PATH].
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64
CMAKE_FRAMEWORK_PATH and CMAKE_APPBUNDLE_PATH variables
[CMAKE_FIND_USE_CMAKE_PATH].
Env variable OpenCV_DIR [CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH].
none
CMAKE_PREFIX_PATH env variable [CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH].
none
CMAKE_FRAMEWORK_PATH and CMAKE_APPBUNDLE_PATH env variables
[CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH].
none
Paths specified by the find_package HINTS option.
none
Standard system environment variables
[CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH].
<a lot of unrelated directories>
CMake User Package Registry [CMAKE_FIND_USE_PACKAGE_REGISTRY].
none
CMake variables defined in the Platform file
[CMAKE_FIND_USE_CMAKE_SYSTEM_PATH].
C:/Users/<username>/AppData/Local/Android/Sdk/cmake/3.18.1
<other unrelated directories>
CMake System Package Registry
[CMAKE_FIND_PACKAGE_NO_SYSTEM_PACKAGE_REGISTRY].
none
Paths specified by the find_package PATHS option.
none
find_package considered the following locations for the Config module:
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/opencv-config.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/opencv-config.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/lib/i686-linux-android/21/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/lib/i686-linux-android/21/opencv-config.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/local/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/local/opencv-config.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/usr/opencv-config.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/OpenCVConfig.cmake
C:/Users/<username>/AppData/Local/Android/Sdk/ndk/23.1.7779620/toolchains/llvm/prebuilt/windows-x86_64/sysroot/opencv-config.cmake
The file was not found.
So, the problem actually was that for Android (and, probably, iOS) CMake sets CMAKE_FIND_ROOT_PATH_MODE_PACKAGE variable (and other CMAKE_FIND_ROOT_PATH_MODE_* variables) to ONLY which makes find_package (and other find_* functions) prefix paths with what is in CMAKE_FIND_ROOT_PATH list.
To override this, one can do some of the following:
Set CMAKE_FIND_ROOT_PATH_MODE_* to BOTH or NEVER
Use CMAKE_FIND_ROOT_PATH_BOTH or NO_CMAKE_FIND_ROOT_PATH for each find_* call
It should also fix the issues when CMake ignores paths from HINTS, PATHS and other prefix construction steps.
I am a newbie with CMake please bear with me. I have a library (libvpop) which I created in c++ using some Boost components (system and date_time). I can link to it without a problem in windows but on Ubuntu, I am getting an error that implies the path to the boost include files cannot be found. Here is the simple CMakeLists.txt file.
cmake_minimum_required(VERSION 3.0.0)
set (Boost_DEBUG 1)
project(vpoplibuser)
find_package(fmt CONFIG REQUIRED)
find_package(Boost CONFIG REQUIRED system )
find_package(Boost CONFIG REQUIRED date_time)
add_executable(vpoplibuser vpoplibuser.cpp vpoplib.h)
find_library(VPLIB libvpop HINTS ~/projects/vpoplibuser/ )
message(STATUS "VPLib include dir: ${VPLIB}")
target_include_directories(vpoplibuser PUBLIC ${PROJECT_SOURCE_DIR} )
target_link_libraries(vpoplibuser PUBLIC ${VPLIB})
target_link_libraries(vpoplibuser PRIVATE fmt::fmt)
target_link_libraries(vpoplibuser PRIVATE Boost::system Boost::date_time)
When I run CMake, I get message:
CMake Error in CMakeLists.txt
Imported target "Boost::system" includes non-existent path "/include"
in its INTERFACE_INCLUDE_DIRECTORIES. Possible reasons include:
The path was deleted, renamed, or moved to another location.
An install or uninstall procedure did not complete successfully.
The installation package was faulty and references files it does not provide.
I have removed and reinstalled Boost. My Boost libraries are at /lib/x86_64-linux-gnu. I cannot figure out exactly where CMake is searching for the boost include file. When I inspect the _BOOST_INCLUDEDIR variable in boost_header-1.71.0/boost_headers-config.cmake it tells me _BOOST_INCLUDEDIR is "/include". I have read something about the PATH variable being an issue so I added /usr to the beginning of my PATH (there is a folder /usr/include/boost which has the boost .hpp files so I was making an assumption that is what CMake is looking for). I have been stuck on this for a couple of days so I would appreciate any advice from the expert community.
I have found a work around thanks to this article: https://github.com/VowpalWabbit/vowpal_wabbit/issues/3003
Something in the Boost cmake process is causing boost to look for the include files at /include when they are really at /usr/include. I created a symbolic link for /include to point to /usr/include and this allowed cmake to find everything. I have not solved the root cause but can move forward with this approach.
I wrote a CMakeLists.txt for a project in C++, which uses OpenCV libraries. When I try to create the project using cmake, I get the next configuration problem:
CMake Error at CMakeLists.txt:15 (find_package):
Could not find module FindOpenCV.cmake or a configuration file for package
OpenCV.
Adjust CMAKE_MODULE_PATH to find FindOpenCV.cmake or set OpenCV_DIR to the
directory containing a CMake configuration file for OpenCV. The file will
have one of the following names:
OpenCVConfig.cmake
opencv-config.cmake
The fact is that I have an environment variable for the path which I use in Visual Studio with no problems. If I don't include OpenCV, then I can configure and generate with no problem, but I need to solve the problem. I don't understand why cmake cannot find the OpenCV path or how to fix it.
I also used the recommendations mentioned in this link:
FindOpenCV.cmake
Does anybody had this problem too?
The error you're seeing is that CMake cannot find a FindOpenCV.cmake file, because cmake doesn't include one out of the box. Therefore you need to find one and put it where cmake can find it:
You can find a good start here. If you're feeling adventurous you can also write your own.
Then add it somewhere in your project and adjust CMAKE_MODULE_PATH so that cmake can find it.
e.g., if you have
CMakeLists.txt
cmake-modules/FindOpenCV.cmake
Then you should do a
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake-modules)
In your CMakeLists.txt file before you do a find_package(OpenCV)
If you are on Linux, you just need to fill the OpenCV_DIR variable with the path of opencv (containing the OpenCVConfig.cmake file)
export OpenCV_DIR=<path_of_opencv>
apt-get install libopencv-dev
export OpenCV_DIR=/usr/share/OpenCV
the header of cpp file should contain:
#include
#include "opencv2/highgui/highgui.hpp"
#include
#include
not original cv.h
find / -name "OpenCVConfig.cmake"
export OpenCV_DIR=/path/found/above
I had this exact same problem. I fixed it by adding the following line to my FindOpenCV.cmake file. Put it anywhere at the top before the rest of the code.
set (OpenCV_DIR /home/cmake/opencv/compiled) #change the path to match your complied directory of opencv
Basically you are telling FindOpenCV.cmake where to find opencv files assuming the other compilation can find the FindOpenCV.cmake
I faced the same error. In my case this "OpenCVConfig.cmake" file is located in /usr/local/share/OpenCV. In CMakeLists.txt add the line
set(OpenCV_DIR /usr/local/share/OpenCV)
as suggested by the error message.
if you are on windows, you can add opencv path to OpenCV_DIR yourself.
(OpenCV_DIR is in the red region)
the path is like "D:/opencv244/build".
you can find file "OpenCVConfig.cmake" under the path.
Another possibility is to denote where you can find OpenCV_DIR in the CMakeLists.txt file. For example, the following cmake scripts work for me:
cmake_minimum_required(VERSION 2.8)
project(performance_test)
set(OpenCV_STATIC ON)
set(OpenCV_CUDA OFF)
set(OpenCV_DIR "${CMAKE_SOURCE_DIR}/../install")
find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
link_directories(${OpenCV_LIB_DIR})
file(GLOB my_source_files ./src/*)
add_executable( performance_test ${my_source_files})
target_link_libraries(performance_test ${OpenCV_LIBS})
Just to remind that you should set OpenCV_STATIC and OpenCV_CUDA as well before you invoke OpenCVConfig.cmake. In my case the built library is static library that does not use CUDA.
On my Fedora machine, when I typed "make" I got an error saying it could not find "cv.h". I fixed this by modifying my "OpenCVConfig.cmake" file.
Before:
SET(OpenCV_INCLUDE_DIRS "${OpenCV_INSTALL_PATH}/include/opencv;${OpenCV_INSTALL_PATH}/include")
SET(OpenCV_LIB_DIR "${OpenCV_INSTALL_PATH}/lib64")
After:
SET(OpenCV_INCLUDE_DIRS "/usr/include/opencv;/usr/include/opencv2")
SET(OpenCV_LIB_DIR "/usr/lib64")
I am using Windows and get the same error message. I find another problem which is relevant.
I defined OpenCV_DIR in my path at the end of the line. However when I typed "path" in the command line, my OpenCV_DIR was not shown. I found because Windows probably has a limit on how long the path can be, it cut my OpenCV_DIR to be only part of what I defined. So I removed some other part of the path, now it works.
I had the same error, I use windows. I add "C:\opencv\build" (opencv folder) to path at the control pannel.
So, That's Ok!!
For me (on Ubuntu), I just run:
sudo apt-get install libopencv-dev
Followed #hugh-pearse 's and #leszek-hanusz 's answers, with a little tweak. I had installed opencv from ubuntu 12.10 repository (libopencv-)* and had the same problem. Couldn't solve it with export OpenCV_DIR=/usr/share/OpenCV/ (since my OpenCVConfig.cmake whas there). It was solved when I also changed some lines on the OpenCVConfig.cmake file:
# ======================================================
# Include directories to add to the user project:
# ======================================================
# Provide the include directories to the caller
#SET(OpenCV_INCLUDE_DIRS "${OpenCV_INSTALL_PATH}/include/opencv;${OpenCV_INSTALL_PATH}/include")
SET(OpenCV_INCLUDE_DIRS "/usr/include/opencv;/usr/include/opencv2")
INCLUDE_DIRECTORIES(${OpenCV_INCLUDE_DIRS})
# ======================================================
# Link directories to add to the user project:
# ======================================================
# Provide the libs directory anyway, it may be needed in some cases.
#SET(OpenCV_LIB_DIR "${OpenCV_INSTALL_PATH}/lib")
SET(OpenCV_LIB_DIR "/usr/lib")
LINK_DIRECTORIES(${OpenCV_LIB_DIR})
And that worked on my Ubuntu 12.10. Remember to add the target_link_libraries(yourprojectname ${OpenCV_LIBS}) in your CMakeLists.txt.
When you install the libraries in the c drive (windows). the CMakeLists.txt shoud be looking like below:
cmake_minimum_required(VERSION 3.0.0)
project(test_opencv VERSION 0.1.0)
include(CTest)
enable_testing()
find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_DIRS})
add_executable(test_opencv main.cpp)
target_link_libraries(test_opencv ${OPENCV_LIBS})
set(CPACK_PROJECT_NAME ${PROJECT_NAME})
set(CPACK_PROJECT_VERSION ${PROJECT_VERSION})
include(CPack)
finding the package and include directories
when building the project in VS code. Run the visual studio code with admin rights as the OpenCV is installed inside C drive.
I added the xgboost library as a git submodule of my project and I'm trying to add it to cmake as a subdirectory. Unfortunately it's not working. A simple hello world project with the following CMakeLists.txt replicates the error that I'm getting.
cmake_minimum_required(VERSION 3.2)
project(foo)
add_subdirectory(xgboost)
add_executable(${PROJECT_NAME} foo.cpp)
target_link_libraries(${PROJECT_NAME} xgboost)
After building the library there is nothing in the xgboost/lib directory so I get the following error.
clang: error: no such file or directory:
'/Users/.../myproject/xgboost/lib/libxgboost.dylib'
I think that the problem is generated in their CMakeLists file since they have two different targets. Maybe cmake is choosing the wrong target but I'm not familiar enough with cmake to figure it out. The following code is from xgboost's CMakeLists.
# Executable
add_executable(runxgboost $<TARGET_OBJECTS:objxgboost> src/cli_main.cc)
set_target_properties(runxgboost PROPERTIES
OUTPUT_NAME xgboost
)
set_output_directory(runxgboost ${PROJECT_SOURCE_DIR})
target_link_libraries(runxgboost ${LINK_LIBRARIES})
# Shared library
add_library(xgboost SHARED $<TARGET_OBJECTS:objxgboost>)
target_link_libraries(xgboost ${LINK_LIBRARIES})
set_output_directory(xgboost ${PROJECT_SOURCE_DIR}/lib)
#Ensure these two targets do not build simultaneously, as they produce outputs with conflicting names
add_dependencies(xgboost runxgboost)
My questions in order of importance are:
Is there any way to fix it without modifying xgboost's CMakeLists.txt file?
Is it reasonable to try to add xgboost to my project as a git submodule?
Is there any reason cmake is not instructing to build the library?
Note: There were several edits to this question since I tried to narrow down the problem and to provide more information.
(I would love to ask for few things beforehand in the comment section, but I have too low reputation to do so, so I will just give it a shot ;))
I have few suspects, and one of them is ${CMAKE_SOURCE_DIR} of the submodule's root CMakeLists.txt. Although the paths are set properly when you run that CMakeLists.txt alone, cmake gets confused the moment you add it as your subdirectory. Have you looked into another directories for your output binaries?
First I would suggest testing this hypothesis, and then I would suggest writing similar, but separate CMakeLists.txt file for xgboost library, and then substitute it in the project temporarily. Unfortunately the CMakeLists.txt filename is hardcoded and there is no possibility to have two files of that kind in one directory; so it seems that the answer to 1) is, that you rather have to change the file.
For the 2): as long as it does not require huge additional logic in your CMakeLists.txt, it makes sense. Other viable option is to create an install target, which you can use to install your xgboost library locally (using CMAKE_INSTALL_PREFIX(doc) variable), and then add the installation path to your CMAKE_LIBRARY_PATH(doc).
After hours of scouring the web and SO for a solution I'm at a standstill. Nothing has worked so far for me...
I'm on Windows, using CLion IDE which uses CMake. My goal is to correctly link SDL2 to my project and use it through #include "SDL.h" which is the correct way.
The format of my CMakeLists.txt file
Specifics regarding the directory where I should have put the MingW development library of SDL2
Any requirements regarding windows ENV variables that I might have to set.
My CMakeLists.txt looks like this:
cmake_minimum_required(VERSION 3.6)
project(sdl2Project)
set(CMAKE_CXX_STANDARD 11)
#This is where sdl2-config.cmake is located
set(CMAKE_PREFIX_PATH ${CMAKE_PREFIX_PATH} "C:/Users/MyUserName/CLibraries/SDL2-2.0.5/x86_64-w64-mingw32/lib/cmake/SDL2")
set(SOURCE_FILES main.cpp)
add_executable(sdl2Project ${SOURCE_FILES})
find_package(sdl2 REQUIRED)
target_include_directories(sdl2Project PUBLIC ${SDL2_INCLUDE_DIRS})
target_link_libraries(sdl2Project ${SDL2_LIBRARIES})
There is no FindSDL2.cmake file used.
The SDL2 library I downloaded from libsdl.org is located in:
C:/Users/MyUserName/CLibraries/SDL2-2.0.5/x86_64-w64-mingw32
I have no experience with CMake so I'm unable to truly understand where the problem stems from. What are the steps I need to take in order for it to find the library and link it correctly??
EDIT:
My Project structure is the following:
sdl2Project
cmake-build-debug
CMakeLists.txt
main.cpp
Looking in your FindSDL2.cmake, you need to provide an hint to CMake about where the library is installed. You could do this by setting an environment variable SDLDIR, but you shouldn't. General advice: you shouldn't use a CMake package that wasn't provided with the sources you're using.
Looking in sources of SDL2, root directory contains a file sdl2-config.cmake.in that should have been configured and installed in your install directory as sdl2-config.cmake: that's the package file you should use.
Am I right guessing the file C:/Users/MyUserName/CLibraries/SDL2-2.0.5/sdl2-config.cmake exists?
If yes, to allow CMake to find it, add your install directory to CMAKE_PREFIX_PATH, before calling find_package:
set(CMAKE_PREFIX_PATH
${CMAKE_PREFIX_PATH}
"C:/Users/MyUserName/CLibraries/SDL2-2.0.5"
)
find_package(sdl2 REQUIRED)
Note the use of "/" in the path instead of "\" which could be interpreted as escaping character. Quotes around the path are only necessary if the path contains whitespaces.
EDIT:
Moreover, you misused target_link_libraries with a wrong target: SDL2 which you don't build in your project, instead of sdl2Project.
You also used a wrong variable: SDL2_LIBRARY instead of SDL2_LIBRARIES; you can see the good variable name by looking in sdl2-config.cmake.
You may consider target_include_directories instead of include_directories, but again the variable name you used is wrong: SDL2_INCLUDE_DIR instead of SDL2_INCLUDE_DIRS.
Try:
target_include_directories(sdl2Project PUBLIC ${SDL2_INCLUDE_DIRS})
target_link_libraries(sdl2Project ${SDL2_LIBRARIES})