re PR tree-optimization/45605 (Missed devirtualization)

re PR tree-optimization/45605 (Missed devirtualization)

	PR tree-optimization/45605
	* cgraphunit.c (cgraph_analyze_functions): Allocate bitmap obstack.
	* gimple-fold.c (static_object_in_other_unit_p): New function.
	(canonicalize_constructor_val): Use it.
	(get_symbol_constant_value): Be reaqdy for canonicalize_constructor_val
	returning NULL.
	(gimple_fold_obj_type_ref_known_binfo): Use static_object_in_other_unit_p.

From-SVN: r164402