[Bug tree-optimization/98552] Make more use of __builtin_undefined for assuring that variables do not change

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98552

--- Comment #2 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
(In reply to Tobias Schlüter from comment #1)
> There's a typo in the example, /= instead of !=.  Fixed example below:

The disease of a Fortran programmer writing C, I guess :-)