[Bug c++/98151] integer output gives different results with -O2 and -O3

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98151

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Compiling with -fsanitize=undefined (as suggested by the bug reporting
guidelines) would have shown the undefined behaviour.