What is the general practice when there is a header conflict?

I am building wine on windows 7 system Here are the conflicting headers
1)

/usr/include/sys/string.h 
char     *_EXFUN(strerror,(int));

2)

  #ifndef HAVE_STRERROR 
const char *strerror(int err);
#endif /* !defined(HAVE_STRERROR) */

I've already configured the makefile, how come there still be conflicts? Is there a good way to prevent these from happening? Thanks Jack

I'm a bit confused why you'd build WINE on Windows, which runs Windows applications natively. I strongly suspect your issues are related to this doublethink. That aside, if ./configure failed to pick up strerror for some reason, you can try adding #define HAVE_STRERROR to your config.h.