https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118939
--- Comment #4 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- I cannot reproduce. Are there relevant Debian-specific patches applied? How has the compiler been configured exactly? I presume that -g does not change anything? If so, can you post the diff of the assembly files generated with -O1 and -O1 -fstack-check respectively?