sem_ch12.adb (Instantiate_Formal_Subprogram): In the subprogram renaming declaration...

2007-12-06  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch12.adb (Instantiate_Formal_Subprogram): In the subprogram
	renaming declaration, use the Slocs of the formal parameters from the
	declaration of the formal subprogram when creating the formal parameter
	entities in the renaming declaration.
	(Analyze_Formal_Type_Declaration): Change the placement of the error
	message concerning illegal known discriminants. It is now posted on the
	type rather than on the first discriminant. This change ensures early
	error report.
	(Freeze_Subprogram_Body): If the generic subprogram is nested within
	the package body that contains the instance, do not generate an
	out-of-place freeze node for the enclosing package.
	(Collect_Previous_Instantiations): Ignore internal instantiations
	generated for formal packages.
	(Validate_Derived_Type_Instance): Add a check that when a formal
	derived type is Known_To_Have_Preelab_Init then the actual type must
	have preelaborable initialization, and issue an error when this
	condition is violated.

From-SVN: r130851

gcc/ada/sem_ch12.adb

@@ -589,8 +589,8 @@ package body Sem_Ch12 is
    --  is true in the declarative region of the formal package, that is to say
    --  in the enclosing generic or instantiation. For an instantiation, the
    --  parameters of the formal package are made visible in an explicit step.
-   --  Furthermore, if the actual is a visible use_clause, these formals must
-   --  be made potentially use_visible as well. On exit from the enclosing
+   --  Furthermore, if the actual has a visible USE clause, these formals must
+   --  be made potentially use-visible as well. On exit from the enclosing
    --  instantiation, the reverse must be done.
 
    --  For a formal package declared without a box, there are conformance rules
@@ -603,7 +603,7 @@ package body Sem_Ch12 is
    --  formals: the visible and private declarations themselves need not be
    --  created.
 
-   --  In Ada2005, the formal package may be only partially parametrized. In
+   --  In Ada 2005, the formal package may be only partially parametrized. In
    --  that case the visibility step must make visible those actuals whose
    --  corresponding formals were given with a box. A final complication
    --  involves inherited operations from formal derived types, which must be
@@ -1575,18 +1575,15 @@ package body Sem_Ch12 is
       Def : Node_Id)
    is
       Loc   : constant Source_Ptr := Sloc (Def);
-      New_N : Node_Id;
 
    begin
       --  Rewrite as a type declaration of a derived type. This ensures that
       --  the interface list and primitive operations are properly captured.
 
-      New_N :=
+      Rewrite (N,
         Make_Full_Type_Declaration (Loc,
           Defining_Identifier => T,
-           Type_Definition => Def);
-
-      Rewrite (N, New_N);
+          Type_Definition     => Def));
       Analyze (N);
       Set_Is_Generic_Type (T);
    end Analyze_Formal_Derived_Interface_Type;
@@ -1626,9 +1623,9 @@ package body Sem_Ch12 is
              Defining_Identifier => T,
              Discriminant_Specifications =>
                Discriminant_Specifications (Parent (T)),
-              Type_Definition =>
-                Make_Derived_Type_Definition (Loc,
-                  Subtype_Indication => Subtype_Mark (Def)));
+             Type_Definition =>
+               Make_Derived_Type_Definition (Loc,
+                 Subtype_Indication => Subtype_Mark (Def)));
 
          Set_Abstract_Present
            (Type_Definition (New_N), Abstract_Present (Def));
@@ -2482,8 +2479,7 @@ package body Sem_Ch12 is
         and then Nkind (Def) /= N_Formal_Private_Type_Definition
       then
          Error_Msg_N
-           ("discriminants not allowed for this formal type",
-            Defining_Identifier (First (Discriminant_Specifications (N))));
+           ("discriminants not allowed for this formal type", T);
       end if;
 
       --  Enter the new name, and branch to specific routine
@@ -3934,7 +3930,6 @@ package body Sem_Ch12 is
          if Nkind (Parent (N)) = N_Compilation_Unit then
             Set_Body_Required (Parent (N), False);
          end if;
-
       end Analyze_Instance_And_Renamings;
 
    --  Start of processing for Analyze_Subprogram_Instantiation
@@ -6430,9 +6425,26 @@ package body Sem_Ch12 is
          --  Freeze package that encloses instance, and place node after
          --  package that encloses generic. If enclosing package is already
          --  frozen we have to assume it is at the proper place. This may be
-         --  a potential ABE that requires dynamic checking.
+         --  a potential ABE that requires dynamic checking. Do not add a
+         --  freeze node if the package that encloses the generic is inside
+         --  the body that encloses the instance, because the freeze node
+         --  would be in the wrong scope. Additional contortions needed if
+         --  the bodies are within a subunit.
+
+         declare
+            Enclosing_Body : Node_Id;
+
+         begin
+            if Nkind (Enc_I) = N_Package_Body_Stub then
+               Enclosing_Body := Proper_Body (Unit (Library_Unit (Enc_I)));
+            else
+               Enclosing_Body := Enc_I;
+            end if;
 
-         Insert_After_Last_Decl (Enc_G, Package_Freeze_Node (Enc_I));
+            if Parent (List_Containing (Enc_G)) /= Enclosing_Body then
+               Insert_After_Last_Decl (Enc_G, Package_Freeze_Node (Enc_I));
+            end if;
+         end;
 
          --  Freeze enclosing subunit before instance
 
@@ -6887,7 +6899,7 @@ package body Sem_Ch12 is
       --  stub in the current compilation, not the subunit itself.
 
       if Nkind (Parent (Gen_Body)) = N_Subunit then
-         Orig_Body :=  Corresponding_Stub (Parent (Gen_Body));
+         Orig_Body := Corresponding_Stub (Parent (Gen_Body));
       else
          Orig_Body := Gen_Body;
       end if;
@@ -7856,7 +7868,7 @@ package body Sem_Ch12 is
             F := First (Parameter_Specifications (New_Spec));
             while Present (F) loop
                Set_Defining_Identifier (F,
-                  Make_Defining_Identifier (Loc,
+                  Make_Defining_Identifier (Sloc (F),
                     Chars => Chars (Defining_Identifier (F))));
                Next (F);
             end loop;
@@ -9299,6 +9311,17 @@ package body Sem_Ch12 is
             Ancestor := Get_Instance_Of (Etype (Base_Type (A_Gen_T)));
          end if;
 
+         --  If the formal derived type has pragma Preelaborable_Initialization
+         --  then the actual type must have preelaborable initialization.
+
+         if Known_To_Have_Preelab_Init (A_Gen_T)
+           and then not Has_Preelaborable_Initialization (Act_T)
+         then
+            Error_Msg_NE
+              ("actual for & must have preelaborable initialization",
+               Actual, Gen_T);
+         end if;
+
          --  Ada 2005 (AI-251)
 
          if Ada_Version >= Ada_05
@@ -10194,12 +10217,12 @@ package body Sem_Ch12 is
       Previous_Instances : constant Elist_Id := New_Elmt_List;
 
       procedure Collect_Previous_Instances (Decls : List_Id);
-      --  Collect all instantiations in the given list of declarations,
-      --  that precedes the generic that we need to load. If the bodies
-      --  of these instantiations are available, we must analyze them,
-      --  to ensure that the public symbols generated are the same when
-      --  the unit is compiled to generate code, and when it is compiled
-      --  in the context of the unit that needs a particular nested instance.
+      --  Collect all instantiations in the given list of declarations, that
+      --  precede the generic that we need to load. If the bodies of these
+      --  instantiations are available, we must analyze them, to ensure that
+      --  the public symbols generated are the same when the unit is compiled
+      --  to generate code, and when it is compiled in the context of a unit
+      --  that needs a particular nested instance.
 
       --------------------------------
       -- Collect_Previous_Instances --
@@ -10214,7 +10237,17 @@ package body Sem_Ch12 is
             if Sloc (Decl) >= Sloc (Inst_Node) then
                return;
 
-            elsif Nkind (Decl) = N_Package_Instantiation then
+            --  If Decl is an instantiation, then record it as requiring
+            --  instantiation of the corresponding body, except if it is an
+            --  abbreviated instantiation generated internally for conformance
+            --  checking purposes only for the case of a formal package
+            --  declared without a box (see Instantiate_Formal_Package). Such
+            --  an instantiation does not generate any code (the actual code
+            --  comes from actual) and thus does not need to be analyzed here.
+
+            elsif Nkind (Decl) = N_Package_Instantiation
+              and then not Is_Internal (Defining_Entity (Decl))
+            then
                Append_Elmt (Decl, Previous_Instances);
 
             elsif Nkind (Decl) = N_Package_Declaration then
@@ -10342,7 +10375,7 @@ package body Sem_Ch12 is
                   end loop;
 
                   --  Collect previous instantiations in the unit that
-                  --  contains the desired generic,
+                  --  contains the desired generic.
 
                   if Nkind (Parent (True_Parent)) /= N_Compilation_Unit
                     and then not Body_Optional