PR c++/44909
	* call.c (add_function_candidate): If we're working on an implicit
	declaration, don't consider candidates that won't match.
	* typeck.c (same_type_ignoring_top_level_qualifiers_p): Now a fn.
	* cp-tree.h (same_type_ignoring_top_level_qualifiers_p): Adjust.

	Revert:
	* cp-tree.h (struct lang_type_class): Add has_user_opeq.
	(TYPE_HAS_USER_OPEQ): New.
	* decl.c (grok_special_member_properties): Set it.
	* class.c (add_implicitly_declared_members): Don't lazily declare
	constructors/operator= if a base or member has a user-declared one.
	(check_bases_and_members, check_bases): Adjust.
	(check_field_decls, check_field_decl): Adjust.

From-SVN: r162233