https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101476
--- Comment #3 from Stas Sergeev <stsp at users dot sourceforge.net> --- Why does it check for a redzone on a non-leaf function? GetAltStackSize() calls to a glibc's getconf and that overwrites a canary. Maybe it shouldn't use/check the redzone on a non-leaf function?