[Bug tree-optimization/65752] Too strong optimizations int -> pointer casts

[ch3root at openwall dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65752

--- Comment #60 from Alexander Cherepanov <ch3root at openwall dot com> ---
It seems to me that problems with the optimization `p == q ? p : q` -> `q`
(comment 15, comment 38, comment 56 etc.) are not specific to past-the-end
pointers. So I filed a separated bug for it with various testcases -- see
pr93052.

The same for the optimization `if (p == q) use p` -> `if (p == q) use q`
(comment 49, comment 52) -- see pr93051.