* c-decl.c (define_label): Warn about identifier conflicts with
	labels in traditional C.

	* c-parse.in (unop +): Warn about the unary plus operator for
	traditional C.

	* c-typeck.c (store_init_value): Warn about automatic aggregate
	initialization for traditional C.

	* invoke.texi (-Wtraditional): Document new warnings.

From-SVN: r34997