How to solve qt5 (packages not found) cmake errors in mac?

Question

I get these following errors during build of a file using CMake:

CMake Warning at CMakeLists.txt:33 (FIND_PACKAGE):

By not providing "FindQt5Core.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "Qt5Core", but
  CMake did not find one.

  Could not find a package configuration file provided by "Qt5Core" with any of the following names:

    Qt5CoreConfig.cmake
    qt5core-config.cmake

Anybody know how to solve this? Thanks in advance

Answer 1

Maybe, you should try to add the proper path to the CMAKE_PREFIX_PATH variable in the environment or config.

export CMAKE_PREFIX_PATH=path_to/Qt/5.9/clang_64:$CMAKE_PREFIX_PATH

Replace path_to with your real path.

Answer 2

You should find the cmake packages in your Qt installation in:

<install_prefix>/lib/cmake

Assuming <install_prefix> is the root path of your installation. Set the variable Qt5_DIR to <install_prefix>/lib/cmake/Qt5 in your configuration and cmake should be able to find all the modules

Answer 3

One possible cause for this error message is outdated CMake code like [1]

find_package(Qt5Core REQUIRED).

Then there is a good chance for solving the problem by changing to

find_package(Qt5 COMPONENTS REQUIRED Core).

[1] http://cmake.3232098.n2.nabble.com/debugging-CMAKE-PREFIX-PATH-td7596290.html