exp_ch3.adb (Build_Variant_Record_Equality): Add pairs of formals for each discrimina...

exp_ch3.adb (Build_Variant_Record_Equality): Add pairs of formals for each discriminant of an unchecked union.

2013-07-05  Ed Schonberg  <schonberg@adacore.com>

	* exp_ch3.adb (Build_Variant_Record_Equality): Add pairs of
	formals for each discriminant of an unchecked union.
	(Make_Eq_Case): Suprogram accepts a list of discriminants. Nested
	variants are supported. New helper function Corresponding_Formal.
	* exp_ch4.adb (Build_Equality_Call): For unchecked unions,
	loop through discriminants to create list of inferred values,
	and modify call to equality routine accordingly.

From-SVN: r200709