http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55270
--- Comment #10 from Marek Polacek <mpolacek at gcc dot gnu.org> 2013-01-28 16:43:31 UTC --- Unfortunately this patch causes a few FAILs, e.g.: /home/polacek/src/gcc/gcc/testsuite/gcc.c-torture/compile/20020604-1.c: In function ‘foo’: /home/polacek/src/gcc/gcc/testsuite/gcc.c-torture/compile/20020604-1.c:15:1: internal compiler error: in calc_dfs_tree, at dominance.c:397 foo (unsigned int n, int x, int y, unsigned char *z) ^ 0x63c87b calc_dfs_tree /home/polacek/src/gcc/gcc/dominance.c:397 0x63ca66 calculate_dominance_info(cdi_direction) /home/polacek/src/gcc/gcc/dominance.c:658 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. I can take a look (but probably only tomorrow).