[PATCH] libstdc++: Fix infinite loop in std::istream::ignore(n, delim) [PR93672]

[Ulrich Drepper]

On Thu, Apr 4, 2024 at 5:29 PM Jonathan Wakely <jwakely@redhat.com> wrote:
> I would appreciate more eyes on this to confirm my conclusions about
> negative int_type values, and the proposed fix, make sense.

The way something like this is handled in glibc's ctype functions is
that both branches are considered.  For isXXX(c) whether c is -v or
256-v the same value is returned (except for EOF which is -1).  This
caused the least number of bad surprises.

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