warning: ordered comparison of function pointers ('PtrToFunc' (aka 'void (*)()') and 'PtrToFunc')

[yurivict]

This clang warning seems to indicate a real coding error:

In file included from src/FileCmd/FileCmdExport.cpp:11:
In file included from src/main/MainWindow.h:16:
In file included from src/Guideline/Guidelines.h:15:
In file included from src/Transformation/Transformation.h:10:
In file included from src/Cmd/CmdMediator.h:11:
In file included from src/Document/Document.h:10:
In file included from src/CoordSystem/CoordSystemContext.h:10:
In file included from src/CoordSystem/CoordSystem.h:10:
In file included from src/CoordSystem/CoordSystemInterface.h:24:
src/Callback/functor.h:1439:41: warning: ordered comparison of function pointers ('PtrToFunc' (aka 'void (*)()') and 'PtrToFunc') [-Wordered-compare-function-pointers]
                        return lhs.func < rhs.func;
                               ~~~~~~~~ ^ ~~~~~~~~