[Bug ipa/106783] [12/13/14/15 Regression] ICE in ipa-modref.cc:analyze_function since r12-5247-ga34edf9a3e907de2

[hubicka at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106783

--- Comment #6 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
The problem is that n/=0 is undefined behavior (so we can optimize out call to
function doing divide by zero), while __builtin_trap is observable and we do
not optimize out code paths that may trip to it.

so isolate-paths is de-facto pesimizing code from this POV.  It is used
__builtin_unreachable things would work.  I think some parts of compiler use
__builtin_unreachable (such as loop unrolling) other __builtin_trap.  It would
be nice to have consistent solution to this.