2017-09-11  Yannick Moy  <moy@adacore.com>

	* gnat1drv.adb (Adjust_Global_Switches): Set
	Check_Validity_Of_Parameters to False in GNATprove mode.
	* opt.ads (Check_Validity_Of_Parameters): Document switch to
	set option.

From-SVN: r251959