http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50757 --- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-10-17 12:33:41 UTC --- Could be fixed by adding C++ and ObjC++ to the Wnonnull definition in c-family/c.opt, or by adjusting the warning() in c-family/c-common.c to use Wformat when compiling C++