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Date: Fri, 11 Jan 2013 18:51:57 +0200
From: Andris Pavenis <andris DOT pavenis AT iki DOT fi>
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To: djgpp-workers AT delorie DOT com
Subject: gcc-4.8.0 and DJGPP time.h
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Reply-To: djgpp-workers AT delorie DOT com

GCC-4.8.0 now defines macro _rdtsc which actually maps to __builtin_ia32_rdtsc().
Macro is defined in file ia32intrin.h (gcc/config/i386/ia32intrin.h in sources,
would go to directory lib/gcc/djgpp/4.80/include for DJGPP). This file must however
be included indirectly through x86intrin.h

The result is a conflict when building libstdc++-v3 and most likely when using it.

I would suggest to include x86intrin.h from time.h instead of defining _rdtsc
there. All symbols defined by ia32intrin.h are prefixed with one or two '_',
so there should hopefully be no namespace pollution.

It would look like

#if ((__GNUC__==4 && __GNUC_MINOR__>=8) || (__GNUC__>4))
#include <x86intrin.h>
#else

current definitions of _rdtsc goes here

#endif

Does such approach look OK?

Andris