* tree.h (contains_placeholder_p): Now returns bool.
	(CONTAINS_PLACEHOLDER_P): New macro.
	(type_contains_placeholder_p): New function.
	* tree.c (save_expr): Remove code avoiding folding COMPONENT_REF.
	(contains_placeholder_p): Now returns bool.
	Rework to use CONTAINS_PLACEHOLDER_P macro.
	(type_contains_placeholder_p): New function.
	* fold-const.c (fold, case COMPONENT_REF): Don't fold if
	type_contains_placeholder_p.
	(fold_range_test, fold_mathfn_compare, fold_inf_compare, fold):
	Use CONTAINS_PLACEHOLDER_P macro.
	* builtins.c (fold_builtin): Likewise.
	* calls.c (initialize_argument_information): Likewise.
	* emit-rtl.c (set_mem_attributes_minus_bitpos): Likewise.
	* explow.c (expr_size): Likewise.
	* expr.c (store_constructor, get_inner_reference): Likewise.
	* function.c (assign_parms): Likewise.
	* stor-layout.c (variable_size): Likewise.

From-SVN: r68969