2017-09-08  Arnaud Charlet  <charlet@adacore.com>

	* exp_intr.adb (Append_Entity_Name): Move to ...
	* sem_util.ads, sem_util.adb: ... here to share it.
	(Subprogram_Name): New subprogram, to compute the name of the enclosing
	subprogram/entity.
	* errutil.adb (Error_Msg): Fill new field Node.
	* erroutc.ads (Subprogram_Name_Ptr): New.
	(Error_Msg_Object): New field Node.
	* erroutc.adb (dmsg, Output_Msg_Text): Take new field Node into account.
	* errout.adb (Error_Msg): New variant with node id parameter.
	Fill new parameter Node when emitting messages. Revert previous
	changes for Include_Subprogram_In_Messages.
	* sem_ch5.adb (Check_Unreachable_Code): Supply Node parameter when
	generating warning message.

2017-09-08  Ed Schonberg  <schonberg@adacore.com>

	* par-ch4.adb (P_Iterated_Component_Association): Place construct
	under -gnat2020 flag, given that it is a future feature of
	the language.
	* sem_aggr.adb (Resolve_Iterated_Component_Association): Mark
	defining identifier as referenced to prevent spurious warnings:
	corresponding loop is expanded into one or more loops whose
	variable has the same name, and the expression uses those names
	and not the original one.

From-SVN: r251883