On 2012-05-15 15:05:02 +0200, Segher Boessenkool wrote: > >>Note that you can test for the exact version of GCC with #ifdef > >>GCC_MAJOR >= 4 && GCC_MINOR >= 7. > > > >They don't exist. > > #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) Hmm, yes, these macros are actually used by MPFR. Note that these macros are also by Intel's compiler ICC, which tries to emulate some GCC features, but doesn't behave exactly like GCC. :( This is a problem for portable code. For those interested, we currently have the following: #define MPFR_VERSION_NUM(a,b,c) (((a) << 16L) | ((b) << 8) | (c)) #if defined(_WIN32) /* Under MS Windows (e.g. with VS2008 or VS2010), Intel's compiler doesn't support/enable extensions like the ones seen under GNU/Linux. https://sympa.inria.fr/sympa/arc/mpfr/2011-02/msg00032.html */ # define __MPFR_ICC(a,b,c) 0 #elif defined(__ICC) # define __MPFR_ICC(a,b,c) (__ICC >= (a)*100+(b)*10+(c)) #elif defined(__INTEL_COMPILER) # define __MPFR_ICC(a,b,c) (__INTEL_COMPILER >= (a)*100+(b)*10+(c)) #else # define __MPFR_ICC(a,b,c) 0 #endif #if defined(__GNUC__) && defined(__GNUC_MINOR__) && ! __MPFR_ICC(0,0,0) # define __MPFR_GNUC(a,i) \ (MPFR_VERSION_NUM(__GNUC__,__GNUC_MINOR__,0) >= MPFR_VERSION_NUM(a,i,0)) #else # define __MPFR_GNUC(a,i) 0 #endif > >GMP and MPFR have such macros. It would be a nice addition to GCC, > >but with the __GCC prefix. > > That's probably why it was added then, in prehistoric times already :-) I wonder why GCC has two different prefixes: __GNUC for the versions and __GCC for some other macros. -- Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
