[Bug middle-end/86471] GCC/libstdc++ outputs inferior code for std::fill and std::fill_n vs std::memset on c-style arrays

[mattreecebentley at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86471

--- Comment #2 from Matt Bentley <mattreecebentley at gmail dot com> ---
(In reply to Andrew Pinski from comment #1)
> Does -O3 bring the performance back?  -O3 enables loop distrubtion which
> should be able to detect these loops.

Just tested - yes.
However this is a fairly trivial testcase and not all projects compile with O3
(most don't).
Clang by comparison optimizes this out at -O2.