PR c/67580
	* c-decl.c (tag_exists_p): New function.
	* c-parser.c (c_parser_declaration_or_fndef): Give a hint when
	struct/union/enum keywords are missing.
	* c-tree.h (tag_exists_p): Declare.

	* gcc.dg/pr67580.c: New test.

From-SVN: r227803