[Bug c/79479] -Woverflow false alarm in unreachable expression

[eggert at gnu dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79479

--- Comment #14 from Paul Eggert <eggert at gnu dot org> ---
Thanks, please feel free to mark this as a duplicate of Bug#4210. I plan to
follow up there.