* opts.h (CL_ERR_NEGATIVE): Define.
	* opts.c (unknown_option_callback): Don't postpone warnings for
	options marked with CL_ERR_NEGATIVE.
	* opts-common.c (decode_cmdline_option): Set CL_ERR_NEGATIVE error
	for negative versions of CL_REJECT_NEGATIVE options.

testsuite:
	* gcc.dg/opts-1.c: Expect errors, not warnings.

From-SVN: r163637