Question

I’m trying to use the cmake’s function:

CHECK_LIBRARY_EXISTS(library function location variable) 

How can I check if the C++ library are available ?

CHECK_LIBRARY_EXISTS(yaml-cpp "YAML::Token" ${YAML-CPP_PATHS} HAVE_YAML-CPP)
IF(HAVE_YAML-CPP)
    MESSAGE(STATUS "YAML-CPP libraries founded: OK")
ENDIF(HAVE_YAML-CPP)

IF(NOT HAVE_YAML-CPP)
    MESSAGE(FATAL_ERROR "ERROR: unable to link YAML::Token")
ENDIF(NOT HAVE_YAML-CPP)

That code snip don’t work.

Answer 1

The CheckLibraryExists module only works for C symbols, not C++. Personally I would just use find_library and find_path to find the library and include path. If the library doesn’t contain the right symbols, the user is going to notice soon enough during the linking…

Since yaml-cpp installs a pkg-config file, you can also use the FindPkgConfig module. However, since yaml-cpp itself is built using CMake, you should encourage them to actually install a yaml-cpp-config.cmake file. See e.g. this tutorial for more information.