gcc - Can't compile executable with CMake -

i started following directory structure:

project        exec            executable.exe        lib            src            include        config            <cmake-generated config file> 

i created library in lib/src folder using cmakefile in lib/src folder. exe compile.

then, moved cmakefile /lib, making sure change source file paths /src/* now, when try compile, libraries compile , link fine, when try link executable, /usr/bin/ld: cannot find -lconfig.

does have idea why happens or how fix it?

here of code:

./cmakelists.txt:      include_directories(config)      set(executable_output_path ${project_binary_dir}/bin)      set(library_output_path ${project_binary_dir}/lib)      add_subdirectory(libs) #library sources      add_subdirectory(exec) #executable sources              configure_file(${core_source_dir}/config/config.h.in                     ${core_source_dir}/config/config.h)   ./libs/cmakelists.txt:      file(glob src ...)      file(glob header ...)      add_library(lib ${src} ${header})    ./exec/cmakelists:       add_executable(executable executable.cpp)       link_directories(${core_source_dir}/lib) #not sure if required       target_link_libraries(executable ${lots_of_libs})   

every library in lots_of_libs can found .a file in lib directory

one problem, not risolutive, this:

link_directories(${core_source_dir}/lib) #not sure if required 

should be:

link_directories(${project_binary_dir}/lib)  

or:

link_directories(${library_output_path})  

anyway, wouldn't need add link_directories path library built within project, if have specified different library_output_path