2009-08-12  Richard Guenther  <rguenther@suse.de>

	* alias.c (get_alias_set): Honor TYPE_STRUCTURAL_EQUALITY_P.
	* gimplify.c (gimplify_modify_expr): Do not use
	lang_hooks.types_compatible_p.
	* tree-ssa.c (useless_type_conversion_p): For aggregates
	just return false if the canonical types differ.

From-SVN: r150695