https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63471
--- Comment #1 from Janne Blomqvist <jb at gcc dot gnu.org> --- Hmm, any idea how to fix it? Apparently just defining _REENTRANT globally might not be a good idea, as some systems may require linking in some other C library (libc_rt or such) then. We don't want to use the GCC -pthread flag (which should take care of necessary linking magic) either, since on systems with weakref support we want to avoid using mutexes etc. in single-threaded programs.
