PR middle-end/87099

	PR middle-end/87099
	* calls.c (maybe_warn_nonstring_arg): Punt early if
	warn_stringop_overflow is zero.  Don't call get_range_strlen
	on 3rd argument, keep iterating until lenrng[1] is INTEGER_CST.
	Swap comparison operands to have constants on rhs.  Only use
	lenrng[1] if non-NULL and INTEGER_CST.  Don't uselessly
	increment lenrng[0].

	* gcc.dg/pr87099.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@263915 138bc75d-0d04-0410-961f-82ee72b054a4