[Bug middle-end/71304] missing strlen optimizations after string truncation by assigning NUL

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71304

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
*** Bug 71305 has been marked as a duplicate of this bug. ***