[Bug tree-optimization/58920] Overeager optimization based on TREE_THIS_NOTRAP

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58920

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
maybe have the front-end emit (if -fdelete-null-pointer-checks is on),
if (ref == NULL) __builtin_unreachable();

This might most cases, how many I don't know.