http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47792
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-02-18 00:23:32 UTC --- why is __GTHREADS defined for thread model 'single' - is that normal? and why isn't __gthread_mutex_destroy in gthr-single.h in scope?