[Bug tree-optimization/71132] [7 Regression] gcc ICE at -O3 on valid code on x86_64-linux-gnu with “seg fault”

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71132

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
So the issue is that loop distribution computes control dependences in the
function once and queries them after processing some loops already (in this
case removing a loop and replacing it with a builtin memset).  In this case
this leads to the loop header being control dependent on the exit test
of the memset loop (sth that doesn't require the endless loop we have here).