[Bug libstdc++/108561] std::endl causes a flush on a bad stream

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108561

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The standard doesn't say anything about not flushing if the put (or any
previous output function) failed.

> Calls os.put(os.widen(’\n’)), then os.flush().