[Bug tree-optimization/111397] Spurious warning "'({anonymous})' is used uninitialized" when calling a __returns_twice__ function (-Wuninitialized -O2)

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111397

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Looks loop copy header change which allowed the warning not to happen.

The warning is about the argument of test_setjmpex. Because GCC does not
realize __builtin_frame_address cannot jump to the test_setjmpex ...

In the case of GCC 12-13, the copy of the loop header happens during
thread-full rather than earlier and inserts:
  _4(ab) = _11(D);

Which is what is warned about.
_11(D) does not get proped into the phi ...