http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60601
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> --- I guess it is not a big deal to do: save_growing_size = obstack_object_size (&obstack); + save_growing_value = NULL; if (save_growing_size > 0) save_growing_value = obstack_finish (&obstack); to workaround the bogus warning. Of course it would be nice to understand why uninit doesn't handle this, since it should be the pretty much easiest case of predicated uninit analysis. --- Comment #6 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- Author: ebotcazou Date: Sun Mar 23 11:29:42 2014 New Revision: 208770 URL: http://gcc.gnu.org/viewcvs?rev=208770&root=gcc&view=rev Log: PR rtl-optimization/60601 * bb-reorder.c (fix_up_fall_thru_edges): Test EDGE_FALLTHRU everywhere. * gcc.c (eval_spec_function): Initialize save_growing_value. Modified: trunk/gcc/ChangeLog trunk/gcc/bb-reorder.c trunk/gcc/gcc.c