[Bug tree-optimization/92860] [9/10/11/12 regression] Global flags affected by -O settings are clobbered by optimize attribute

[marxin at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92860

--- Comment #68 from Martin Liška <marxin at gcc dot gnu.org> ---
> Righto. This is proving unexpectedly hard to reproduce.

Ok, so please tell me exact steps how to reproduce it.