2007-04-20 Hristian Kirtchev <kirtchev@adacore.com>

	    Robert Dewar  <dewar@adacore.com>
	    Ed Schonberg  <schonberg@adacore.com>
	    Gary Dismukes  <dismukes@adacore.com>

	* exp_ch2.adb: Remove "with" and "use" clauses for Namet and Snames.
	Add "with" and "use" clauses for Sem_Attr.
	(Expand_Current_Value): Do not replace occurences of attribute
	references where the prefix must be a simple name.

	* sem_attr.ads, sem_attr.adb: Remove "with" and "use" clauses for
	Namet. Add new arrays Attribute_Name_Modifies_Prefix and
	Attribute_Requires_Simple_Name_Prefix.
	(Name_Modifies_Prefix): Body of new function.
	(Requires_Simple_Name_Prefix): Body of new function.
	(Resolve_Attribute, case Access): Improve error message for case of
	mismatched conventions.
	(Analyze_Attribute, case 'Tag): The prefix the attribute cannot be of an
	incomplete type.
	(Analyze_Attribute, case 'Access): If the type of the prefix is a
	constrained subtype for a nominal unconstrained type, use its base type
	to check for conformance with the context.
	(Resolve_Attribute): Remove test of the access type being associated
	with a return statement from condition for performing accessibility
	checks on access attributes, since this case is now captured by
	Is_Local_Anonymous_Access.
	(Analyze_Access_Attribute): Set Address_Taken on entity
	(Analyze_Attribute, case Address): Set Address_Taken on entity
	(OK_Self_Reference): Traverse tree to locate enclosing aggregate when
	validating an access attribute whose prefix is a current instance.
	(Resolve_Attribute): In case of attributes 'Code_Address and 'Address
	applied to dispatching operations, if freezing is required then we set
	the attribute Has_Delayed_Freeze in the prefix's entity.
	(Check_Local_Access): Set flag Suppress_Value_Tracking_On_Call in
	current scope if access of local subprogram taken
	(Analyze_Access_Attribute): Check legality of self-reference even if the
	expression comes from source, as when a single component association in
	an aggregate has a box association.
	(Resolve_Attribute, case 'Access): Do not apply accessibility checks to
	the prefix if it is a protected operation and the attribute is
	Unrestricted_Access.
	(Resolve_Attribute, case 'Access): Set the Etype of the attribute
	reference to the base type of the context, to force a constraint check
	when the context is an access subtype with an explicit constraint.
	(Analyze_Attribute, case 'Class): If the prefix is an interface and the
	node is rewritten as an interface conversion. leave unanalyzed after
	resolution, to ensure that type checking against the context will take
	place.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@125395 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 15 insertions, 1 deletions

diff --git a/gcc/ada/sem_attr.ads b/gcc/ada/sem_attr.ads
index c80852aa7d9..6e15eaf720d 100644
--- a/gcc/ada/sem_attr.ads
+++ b/gcc/ada/sem_attr.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---          Copyright (C) 1992-2006, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2007, Free Software Foundation, Inc.         --
 --                                                                          --
 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
 -- terms of the  GNU General Public License as published  by the Free Soft- --
@@ -32,6 +32,7 @@
 --  This spec also documents all GNAT implementation defined pragmas
 
 with Exp_Tss; use Exp_Tss;
+with Namet;   use Namet;
 with Snames;  use Snames;
 with Types;   use Types;
 
@@ -541,6 +542,19 @@ package Sem_Attr is
    --  in appropriate contexts (i.e. in subtype marks, or as prefixes for
    --  other attributes).
 
+   function Name_Modifies_Prefix (Nam : Name_Id) return Boolean;
+   --  Determine whether the name of an attribute reference modifies the
+   --  contents of its prefix. "Read" is such an attribute.
+
+   function Requires_Simple_Name_Prefix (Nam : Name_Id) return Boolean;
+   --  Determine whether the name of an attribute reference requires a simple
+   --  name rather than a value as its prefix. Such prefixes do not need to be
+   --  optimized. For instance in the following example:
+   --     I : constant Integer := 5;
+   --     S : constant Integer := I'Size;
+   --  "Size" requires a simple name prefix since "5'Size" does not make
+   --  sense.
+
    procedure Resolve_Attribute (N : Node_Id; Typ : Entity_Id);
    --  Performs type resolution of attribute. If the attribute yields a
    --  universal value, mark its type as that of the context. On the other