http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46155
--- Comment #11 from Kalle Olavi Niemitalo <kon at iki dot fi> 2010-10-24 19:47:27 UTC --- (In reply to comment #7) > In your opinion, are IBM wrong to define fprnd_t in /usr/include/float.h? IBM's definition of fprnd_t in <float.h> is within #ifdef _ALL_SOURCE. I presume _ALL_SOURCE is not defined when IBM's compiler is used in ISO C conforming mode. AFAIK, adding non-standard definitions to standard header files in non-conforming modes is a common practice. The <float.h> that GCC installed on AIX is identical to gcc/ginclude/float.h in the GCC 4.2.4 sources. I can understand if GCC developers don't want to introduce OS-specific sections in it.