[Bug middle-end/66021] GCC miscompiles Z3

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66021

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Basically GCC understands that memcpy takes non-null arguments and optimizes
based on that.