audiomanager.pc.in sets Cflags to include AUDIOMANAGER_CMAKE_CXX_FLAGS, which in turn brings in the -pedantic flag. This is intrusive to the user of that pkg-config, enforcing to provide own code to be compatible - and sometimes impossible if using incompatible 3rd party code.
What is the intention of including extraneous flags here?  -pedantic should not be enforced in the interface.