[Bug tree-optimization/115337] wrong code with _BitInt() __builtin_stdc_first_leading_one/__builtin_clzg (with -1 as second arg) at -O2

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115337

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 58339
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58339&action=edit
gcc15-pr115337-1.patch

Untested fix.