https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126848
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Ah, ssa_undefined_value_p returns true for .DEFERRED_INIT. Guess it shouldn't do that for AUTO_INIT_CXX26 and tree-ssa-uninit.cc (has_undefined_value_p) should special case that.
