gcc/ChangeLog:
	PR driver/78877
	* opts.c: Include "spellcheck.h"
	(struct string_fragment): New struct.
	(struct edit_distance_traits<const string_fragment &>): New
	struct.
	(get_closest_sanitizer_option): New function.
	(parse_sanitizer_options): Offer suggestions for unrecognized arguments.

gcc/testsuite/ChangeLog:
	PR driver/78877
	* gcc.dg/spellcheck-options-14.c: New test case.
	* gcc.dg/spellcheck-options-15.c: New test case.
	* gcc.dg/spellcheck-options-16.c: New test case.
	* gcc.dg/spellcheck-options-17.c: New test case.

From-SVN: r244325