[Bug tree-optimization/94015] [10 Regression] Another assignment incorrectly omitted by -foptimize-strlen

[nate at thatsmathematics dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94015

--- Comment #4 from Nate Eldredge <nate at thatsmathematics dot com> ---
Comment on attachment 47959
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47959
gcc10-pr94015.patch

I'm not qualified to opine on the proposed fix, but just wanted to note that,
as I mentioned above, running your testcase doesn't actually exercise the bug
on amd64/linux because the high byte of the address of the literal is always
zero, so the test passes whether s[7]='\0' is "optimized" out or not.  More
tests are always good, I suppose, but I just want to emphasize that running
this testcase is not the way to check whether the bug is fixed.  I wasn't able
to come up with a good runtime way to check whether the code was correctly
compiled.  Maybe someone more clever than me can think of a way?