https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69971
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> --- Yes, the warning does exist to warn about unsafe calls to the function (I added it here: https://gcc.gnu.org/ml/gcc-patches/2015-07/msg01702.html). This bug was meant to suggest a way to make the built-in safer by expanding it as a loop rather than stream of repetitive load instructions, while also making the code more space efficient. But emitting a loop alone with no other checks (except for the level) won't actually make the function safer. The loop would also have to validate the address at each iteration. I'm not sure how easy, efficient, or reliable this might be. In the of a corrupted stack it certainly wouldn't be reliable.
