[multiple changes]

2014-07-16  Vadim Godunko  <godunko@adacore.com>

	* a-coinho-shared.adb (Adjust): Create
	copy of internal shared object and element when source container
	is locked.
	(Copy): Likewise.
	(Query_Element): Likewise.
	(Update_Element): Likewise.
	(Constant_Reference): Likewise. Raise Constraint_Error on attempt
	to get reference for empty holder.
	(Reference): Likewise.

2014-07-16  Thomas Quinot  <quinot@adacore.com>

	* exp_ch4.adb (Find_Hook_Context): New subprogram, extracted
	from Process_Transient_Oject.
	* exp_ch4.ads: Ditto.
	* exp_ch9.adb (Build_Class_Wide_Master): Insert the _master
	declaration as an action on the topmost enclosing expression,
	not on a possibly conditional subexpreession.

From-SVN: r212645

gcc/ada/ChangeLog

 2014-07-16  Vadim Godunko  <godunko@adacore.com>
 
+	* a-coinho-shared.adb (Adjust): Create
+	copy of internal shared object and element when source container
+	is locked.
+	(Copy): Likewise.
+	(Query_Element): Likewise.
+	(Update_Element): Likewise.
+	(Constant_Reference): Likewise. Raise Constraint_Error on attempt
+	to get reference for empty holder.
+	(Reference): Likewise.
+
+2014-07-16  Thomas Quinot  <quinot@adacore.com>
+
+	* exp_ch4.adb (Find_Hook_Context): New subprogram, extracted
+	from Process_Transient_Oject.
+	* exp_ch4.ads: Ditto.
+	* exp_ch9.adb (Build_Class_Wide_Master): Insert the _master
+	declaration as an action on the topmost enclosing expression,
+	not on a possibly conditional subexpreession.
+
+2014-07-16  Vadim Godunko  <godunko@adacore.com>
+
 	* a-coinho.adb, a-coinho-shared.adb, a-coinho.ads, a-coinho-shared.ads:
 	Fix parameter mode of Update_Element.
 

gcc/ada/a-coinho-shared.adb

@@ -57,7 +57,20 @@ package body Ada.Containers.Indefinite_Holders is
    overriding procedure Adjust (Container : in out Holder) is
    begin
       if Container.Reference /= null then
-         Reference (Container.Reference);
+         if Container.Busy = 0 then
+            --  Container is not locked, reuse existing internal shared object.
+
+            Reference (Container.Reference);
+         else
+            --  Otherwise, create copy of both internal shared object and
+            --  element.
+
+            Container.Reference :=
+               new Shared_Holder'
+                 (Counter => <>,
+                  Element =>
+                     new Element_Type'(Container.Reference.Element.all));
+         end if;
       end if;
 
       Container.Busy := 0;
@@ -113,16 +126,34 @@ package body Ada.Containers.Indefinite_Holders is
    ------------------------
 
    function Constant_Reference
-     (Container : aliased Holder) return Constant_Reference_Type
-   is
-      Ref : constant Constant_Reference_Type :=
-              (Element => Container.Reference.Element.all'Access,
-               Control => (Controlled with Container'Unrestricted_Access));
-      B   : Natural renames Ref.Control.Container.Busy;
+     (Container : aliased Holder) return Constant_Reference_Type is
    begin
-      Reference (Ref.Control.Container.Reference);
-      B := B + 1;
-      return Ref;
+      if Container.Reference = null then
+         raise Constraint_Error with "container is empty";
+
+      elsif Container.Busy = 0
+        and then not System.Atomic_Counters.Is_One
+                       (Container.Reference.Counter)
+      then
+         --  Container is not locked and internal shared object is used by
+         --  other container, create copy of both internal shared object and
+         --  element.
+
+         Container'Unrestricted_Access.Reference :=
+            new Shared_Holder'
+              (Counter => <>,
+               Element => new Element_Type'(Container.Reference.Element.all));
+      end if;
+
+      declare
+         Ref : constant Constant_Reference_Type :=
+                 (Element => Container.Reference.Element.all'Access,
+                  Control => (Controlled with Container'Unrestricted_Access));
+      begin
+         Reference (Ref.Control.Container.Reference);
+         Ref.Control.Container.Busy := Ref.Control.Container.Busy + 1;
+         return Ref;
+      end;
    end Constant_Reference;
 
    ----------
@@ -133,10 +164,21 @@ package body Ada.Containers.Indefinite_Holders is
    begin
       if Source.Reference = null then
          return (Controlled with null, 0);
-      else
+      elsif Source.Busy = 0 then
+         --  Container is not locked, reuse internal shared object.
+
          Reference (Source.Reference);
 
          return (Controlled with Source.Reference, 0);
+      else
+         --  Otherwise, create copy of both internal shared object and elemet.
+
+         return
+           (Controlled with
+               new Shared_Holder'
+                 (Counter => <>,
+                  Element => new Element_Type'(Source.Reference.Element.all)),
+               0);
       end if;
    end Copy;
 
@@ -224,6 +266,19 @@ package body Ada.Containers.Indefinite_Holders is
    begin
       if Container.Reference = null then
          raise Constraint_Error with "container is empty";
+
+      elsif Container.Busy = 0
+        and then not System.Atomic_Counters.Is_One
+                       (Container.Reference.Counter)
+      then
+         --  Container is not locked and internal shared object is used by
+         --  other container, create copy of both internal shared object and
+         --  element.
+
+         Container'Unrestricted_Access.Reference :=
+            new Shared_Holder'
+              (Counter => <>,
+               Element => new Element_Type'(Container.Reference.Element.all));
       end if;
 
       B := B + 1;
@@ -284,15 +339,34 @@ package body Ada.Containers.Indefinite_Holders is
    end Reference;
 
    function Reference
-     (Container : aliased in out Holder) return Reference_Type
-   is
-      Ref : constant Reference_Type :=
-              (Element => Container.Reference.Element.all'Access,
-               Control => (Controlled with Container'Unrestricted_Access));
+     (Container : aliased in out Holder) return Reference_Type is
    begin
-      Reference (Ref.Control.Container.Reference);
-      Container.Busy := Container.Busy + 1;
-      return Ref;
+      if Container.Reference = null then
+         raise Constraint_Error with "container is empty";
+
+      elsif Container.Busy = 0
+        and then not System.Atomic_Counters.Is_One
+                       (Container.Reference.Counter)
+      then
+         --  Container is not locked and internal shared object is used by
+         --  other container, create copy of both internal shared object and
+         --  element.
+
+         Container.Reference :=
+            new Shared_Holder'
+              (Counter => <>,
+               Element => new Element_Type'(Container.Reference.Element.all));
+      end if;
+
+      declare
+         Ref : constant Reference_Type :=
+                 (Element => Container.Reference.Element.all'Access,
+                  Control => (Controlled with Container'Unrestricted_Access));
+      begin
+         Reference (Ref.Control.Container.Reference);
+         Ref.Control.Container.Busy := Ref.Control.Container.Busy + 1;
+         return Ref;
+      end;
    end Reference;
 
    ---------------------
@@ -387,6 +461,19 @@ package body Ada.Containers.Indefinite_Holders is
    begin
       if Container.Reference = null then
          raise Constraint_Error with "container is empty";
+
+      elsif Container.Busy = 0
+        and then not System.Atomic_Counters.Is_One
+                       (Container.Reference.Counter)
+      then
+         --  Container is not locked and internal shared object is used by
+         --  other container, create copy of both internal shared object and
+         --  element.
+
+         Container'Unrestricted_Access.Reference :=
+            new Shared_Holder'
+              (Counter => <>,
+               Element => new Element_Type'(Container.Reference.Element.all));
       end if;
 
       B := B + 1;

gcc/ada/exp_ch4.ads

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---          Copyright (C) 1992-2013, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2014, 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- --
@@ -103,4 +103,11 @@ package Exp_Ch4 is
    --  have special circuitry in Expand_N_Type_Conversion to promote both of
    --  the operands to type Integer.
 
+   function Find_Hook_Context (N : Node_Id) return Node_Id;
+   --  Determine a suitable node on which to attach actions related to N
+   --  that need to be elaborated unconditionally (i.e. in general the topmost
+   --  expression of which N is a subexpression, which may or may not be
+   --  evaluated, for example if N is the right operand of a short circuit
+   --  operator).
+
 end Exp_Ch4;

gcc/ada/exp_ch9.adb

@@ -29,6 +29,7 @@ with Einfo;    use Einfo;
 with Elists;   use Elists;
 with Errout;   use Errout;
 with Exp_Ch3;  use Exp_Ch3;
+with Exp_Ch4;  use Exp_Ch4;
 with Exp_Ch6;  use Exp_Ch6;
 with Exp_Ch11; use Exp_Ch11;
 with Exp_Dbug; use Exp_Dbug;
@@ -1151,7 +1152,6 @@ package body Exp_Ch9 is
       then
          declare
             Master_Decl : Node_Id;
-
          begin
             Set_Has_Master_Entity (Master_Scope);
 
@@ -1169,7 +1169,7 @@ package body Exp_Ch9 is
                   Make_Explicit_Dereference (Loc,
                     New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
 
-            Insert_Action (Related_Node, Master_Decl);
+            Insert_Action (Find_Hook_Context (Related_Node), Master_Decl);
             Analyze (Master_Decl);
 
             --  Mark the containing scope as a task master. Masters associated