[Bug c/64459] __attribute__((returns_nonnull)) creates wrong code on amd64

[rur...@x-ray.at]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64459

--- Comment #4 from Reini Urban <rur...@x-ray.at> ---
maybe the script is of value to anyone:
https://gist.github.com/rurban/b8b951d03ff22734f05b