a-stzsup.adb, [...]: Fix warnings for range tests optimized out.

a-stzsup.adb, [...]: Fix warnings for range tests optimized out.

2007-08-14  Robert Dewar  <dewar@adacore.com>
	    Gary Dismukes  <dismukes@adacore.com>
	    Ed Schonberg  <schonberg@adacore.com>
	    Thomas Quinot  <quinot@adacore.com>

	* a-stzsup.adb, nlists.adb, lib-util.adb, treepr.adb,
	a-stwisu.adb, a-strsup.adb: Fix warnings for range
	tests optimized out.

	* exp_ch4.adb (Expand_N_In): Add warnings for range tests optimized out.
	(Get_Allocator_Final_List): For the case of an anonymous access type
	that has a specified Associated_Final_Chain, do not go up to the
	enclosing scope.
	(Expand_N_Type_Conversion): Test for the case of renamings of access
	parameters when deciding whether to apply a run-time accessibility
	check.
	(Convert_Aggr_In_Allocator): Use Insert_Actions to place expanded
	aggregate code before allocator, and ahead of declaration for
	temporary, to prevent access before elaboration when the allocator is
	an actual for an access parameter.
	(Expand_N_Type_Conversion): On an access type conversion involving an
	access parameter, do not apply an accessibility check when the
	operand's original node was an attribute other than 'Access. We now
	create access conversions for the expansion of 'Unchecked_Access and
	'Unrestricted_Access in certain cases and clearly accessibility should
	not be checked for those.

	* exp_ch6.ads, exp_ch6.adb (Add_Call_By_Copy_Code): For an actual that
	includes a type conversion of a packed component that has been expanded,
	recover the original expression for the object, and use this expression
	in the post-call assignment statement, so that the assignment is made
	to the object and not to a back-end temporary.
	(Freeze_Subprogram): In case of primitives of tagged types not defined
	at the library level force generation of code to register the primitive
	in the dispatch table. In addition some code reorganization has been
	done to leave the implementation clear.
	(Expand_Call): When expanding an inherited implicit conversion,
	preserve the type of the inherited function after the intrinsic
	operation has been expanded.

	* exp_ch2.ads, exp_ch2.adb
	(Expand_Entry_Parameter.In_Assignment_Context): An implicit dereference
	of an entry formal appearing in an assignment statement does not assign
	to the formal.
	(Expand_Current_Value): Instead of calling a routine to determine
	whether the prefix of an attribute reference should be optimized or
	not, prevent the optimization of such prefixes all together.

	* lib-xref.adb (Generate_Reference.Is_On_LHS): An indexed or selected
	component whose prefix is known to be of an access type is an implicit
	dereference and does not assign to the prefix.

From-SVN: r127411