How to prevent macro redefinition

Question

After working some time on my project, this warning begins to appear:

2>Game.cpp
2>c:\\program files\\microsoft sdks\\windows\\v6.0a\\include\\windef.h         


        

Answer 1

Unfortunately or fortunately, no. There is no such tool that automates it. You have to go read the code in those header files, figure out what is going on and take appropriate actions.

The most you can do is

1. Check if macro is defined using ifdef or if defined(...) or if !defined(...) preprocessor constructs.
2. Undefine macro using undef.

Only ANSI C considers macro redefinition an error.