[Bug libstdc++/105580] [13/14/15 Regression] warning "potential null pointer dereference" raised when using istreambuf_iterator and any "-O" flag

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105580

--- Comment #19 from Tomasz Kamiński <tkaminsk at gcc dot gnu.org> ---
Back-ported up to v13.