[Bug middle-end/121593] Miscompiles small function to produce endless(?) loop

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121593

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Also I am trying to understand which version has the bug? The one without the
patch (and with `__attribute__((optimize("O0"))` removed) or the one with the
patch (and with `__attribute__((optimize("O0"))` removed)?

Does changing `optimize("O0")` to noipa help fix the issue?

Also which function is the hang in? Is it in
QXmlStreamWriterPrivate::writeEscaped or something else?