http://gcc.gnu.org/bugzilla/show_bug.cgi?id=61026
--- Comment #8 from Oleg Endo <olegendo at gcc dot gnu.org> --- (In reply to Jan-Benedict Glaw from comment #7) > I'm not 100% sure, but I guess this fix breaks building GCC on > gcc111.fsffrance.org . All build details can be found here: > http://toolchain.lug-owl.de/buildbot/show_build_details.php?id=218196 Looks like an include order problem of C system includes and C++ stdlib includes, probably caused by specific clib / C++ stdlib versions or combinations on the system. Could you please try to add an #include <unistd.h> before the C++ includes and see if it resolves some of the errors/changes anything? It's probably not going to be the final fix for the problem, but might give some clues.