2014-02-19 Ed Schonberg <schonberg@adacore.com>

2014-02-19  Ed Schonberg  <schonberg@adacore.com>

	* style.adb (Missing_Overriding): Warning does not apply in
	language versions prior to Ada 2005.
	* snames.ads-tmpl: Add Name_Iterable and Attribute_Iterable.
	* sem_attr.adb: Add Attribute_Iterable where needed.
	* exp_attr.adb: ditto.
	* exp_ch5.adb (Expand_Formal_Container_Loop): New procedure to
	handle loops and quantified expressions over types that have an
	iterable aspect.  Called from Expand_Iterator_Loop.
	* sem_ch5.adb (Analyze_Iterator_Specification): Recognize types
	with Iterable aspect.
	* sem_ch13.adb (Validate_Iterable_Aspect): Verify that the
	subprograms specified in the Iterable aspect have the proper
	signature involving container and cursor.
	(Check_Aspect_At_Freeze_Point): Analyze value of iterable aspect.
	* sem_ch13.ads (Validate_Iterable_Aspect): New subprogram.
	* sem_util.ads, sem_util.adb (Get_Iterable_Type_Primitive):
	New procedure to retrieve one of the primitives First, Last,
	or Has_Element, from the value of the iterable aspect of a
	formal container.
	(Is_Container_Element): Predicate to recognize expressions
	that denote an element of one of the predefined containers,
	for possible optimization.  This subprogram is not currently
	used, pending ARG discussions on the legality of the proposed
	optimization. Worth preserving for eventual use.
	(Is_Iterator): Recognize formal container types.
	* aspects.ads, aspects.adb: Add Aspect_Iterable where needed.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@207881 138bc75d-0d04-0410-961f-82ee72b054a4