[Bug libstdc++/42857] std::istream::ignore(std::streamsize n) calls unnecessary underflow

[ncm at cantrip dot org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42857

--- Comment #9 from ncm at cantrip dot org ---
(In reply to Jonathan Wakely from comment #8)
> Probably changed by one of the patches for PR 94749 or PR 96161, although I
> still see two reads for the first example.

Thank you, I was mistaken. This bug is still present in g++-10.