http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47491
--- Comment #2 from Janne Blomqvist <jb at gcc dot gnu.org> 2011-01-27 16:10:41 UTC --- Some git-grepping showed that at least libjava has in configure.ac AC_DEFINE(_POSIX_PTHREAD_SEMANTICS, 1, [Required define if using POSIX threads]) and in case Boehm GC is not used (which libgfortran never uses): AC_DEFINE(_REENTRANT, 1, [Required define if using POSIX threads]) However, if I understand gcc/config/ correctly, _REENTRANT should be automatically set for all targets that need it. Also in gcc/config a few targets set -D_POSIX_C_SOURCE=199506L (not Solaris, though). But apparently we shouldn't go and set this somewhere in libgfortran? That is, at least no other library does this.. Moreover, in config/extensions.m4 there is the macro AC_USE_SYSTEM_EXTENSIONS that seems to define _POSIX_PTHREAD_SEMANTICS on Solaris. This seems to me the most sensible solution. Would that work?
