2019-12-13  Justin Squirek  <squirek@adacore.com>

gcc/ada/

	* sem_ch6.adb (Check_Overriding_Indicator): Modify condition to
	take into account the modification of the Is_Hidden flag within
	generic instances.
	(Verify_Overriding_Indicator): Add an exception for controlled
	primitives within an instance.

From-SVN: r279340