[Ada] Spurious errors on tag indeterminate calls.

[Arnaud Charlet <charlet at adacore dot com>]

This patch removes spurious errors on tag indeterminate calls that are
actuals of other dispatching calls that may themselves be tag-indeterminate.

Full test in ACATS 4.0G BC60004

Tested on x86_64-pc-linux-gnu, committed on trunk

2016-04-18  Ed Schonberg  <schonberg@adacore.com>

	* sem_disp.adb (Check_Dispatching_Call): Major rewriting to
	handle some complex cases of tag indeterminate calls that are
	actuals in other dispatching calls that are themselves tag
	indeterminate.
	(Check_Dispatching_Context): Add parameter to support recursive
	check for an enclosing construct that may provide a tag for a
	tag-indeterminate call.

Attachment: difs
Description: Text document