如何避免在 cmake 中自动链接 Qt5 库？

Question

I am intending to compile the following opencv code:

#include <stdio.h>
#include <opencv2/opencv.hpp>

using namespace cv;

int main(int argc, char** argv )
{
   printf("hello world \n");
   return 0;
}

My CMakeLists.txt is the following:

cmake_minimum_required(VERSION 2.8)
find_package( OpenCV REQUIRED )
project( main )
add_executable(main main.cpp )
target_link_libraries( main ${OpenCV_LIBS} )

When compiled the result is as follows:

[ 50%] Building CXX object CMakeFiles/main.dir/main.cpp.o
[100%] Linking CXX executable main
/usr/bin/ld: cannot find -lQt5::Core
/usr/bin/ld: cannot find -lQt5::Gui
/usr/bin/ld: cannot find -lQt5::Widgets
/usr/bin/ld: cannot find -lQt5::Test
/usr/bin/ld: cannot find -lQt5::Concurrent
/usr/bin/ld: cannot find -lQt5::OpenGL
collect2: error: ld returned 1 exit status
CMakeFiles/main.dir/build.make:143: recipe for target 'main' failed
make[2]: *** [main] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/main.dir/all' failed
make[1]: *** [CMakeFiles/main.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2

I believe that CMake in automatic way include Qt5 libraries, I would want to know how avoid this situation.

Answer 1

Ideology of CMake is to never add something that is not required. It is possible that Qt libs were added to configuration list of CMake.

They might be featured in standard variable you use. You can print content by

message(STATUS "OpenCV_LIBS = ${OpenCV_LIBS}") 

Configuration file looks OpenCVConfig.cmake.in and may include other files which for some reason were changed.