[Bug c/85623] strncmp() warns about attribute 'nonstring' incorrectly in -Wstringop-overflow

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85623

--- Comment #5 from Martin Sebor <msebor at gcc dot gnu.org> ---
Patch committed to trunk in r260541.