PR middle-end/89663
	* builtins.c (expand_builtin_int_roundingfn,
	expand_builtin_int_roundingfn_2): Return NULL_RTX instead of
	gcc_unreachable if validate_arglist fails.

	* gcc.c-torture/compile/pr89663-1.c: New test.
	* gcc.c-torture/compile/pr89663-2.c: New test.

From-SVN: r269605