* except.c (remove_unreachable_regions): New.
	(free_eh_status): Clear exception_handler_labels.
	(convert_from_eh_region_ranges): Call remove_unreachable_regions.
	(find_exception_handler_labels): Don't add the same label more than
	once.
	(remove_exception_handler_label): Don't die if
	find_exception_handler_labels hasn't been called for the current
	function yet.

From-SVN: r48845