[multiple changes]

2017-05-02  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch6.adb (Fully_Conformant_Expressions): Two entity
	references are fully conformant if they are both expansions
	of the discriminant of a protected type, within one of the
	protected operations. One occurrence may be expanded into a
	constant declaration while the other is an input parameter to
	the corresponding generated subprogram.

2017-05-02  Justin Squirek  <squirek@adacore.com>

	* sem_ch3.adb (Check_For_Null_Excluding_Components): Created for
	recursivly searching composite-types for null-excluding access
	types and verifying them.
	(Analyze_Object_Declaration): Add a
	call to Check_Null_Excluding_Components for static verification
	of non-initialized objects.
	* checks.adb, checks.ads (Null_Exclusion_Static_Checks): Added
	a parameter for a composite-type's component and an extra case
	for printing component information.

2017-05-02  Yannick Moy  <moy@adacore.com>

	* sem_ch10.adb (Analyze_Subunit): Take
	configuration pragma into account when restoring appropriate
	pragma for analysis of subunit.

2017-05-02  Justin Squirek  <squirek@adacore.com>

	* s-tasren.adb, s-tasini.adb, s-taprop-linux.adb,
	s-mudido-affinity.adb,, a-exetim-posix.adb, a-direio.adb,
	g-socket.adb, s-taenca.adb, s-fileio.adb: Remove unused use-type
	clauses from the runtime.

From-SVN: r247465

gcc/ada/ChangeLog

+2017-05-02  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_ch6.adb (Fully_Conformant_Expressions): Two entity
+	references are fully conformant if they are both expansions
+	of the discriminant of a protected type, within one of the
+	protected operations. One occurrence may be expanded into a
+	constant declaration while the other is an input parameter to
+	the corresponding generated subprogram.
+
+2017-05-02  Justin Squirek  <squirek@adacore.com>
+
+	* sem_ch3.adb (Check_For_Null_Excluding_Components): Created for
+	recursivly searching composite-types for null-excluding access
+	types and verifying them.
+	(Analyze_Object_Declaration): Add a
+	call to Check_Null_Excluding_Components for static verification
+	of non-initialized objects.
+	* checks.adb, checks.ads (Null_Exclusion_Static_Checks): Added
+	a parameter for a composite-type's component and an extra case
+	for printing component information.
+
+2017-05-02  Yannick Moy  <moy@adacore.com>
+
+	* sem_ch10.adb (Analyze_Subunit): Take
+	configuration pragma into account when restoring appropriate
+	pragma for analysis of subunit.
+
+2017-05-02  Justin Squirek  <squirek@adacore.com>
+
+	* s-tasren.adb, s-tasini.adb, s-taprop-linux.adb,
+	s-mudido-affinity.adb,, a-exetim-posix.adb, a-direio.adb,
+	g-socket.adb, s-taenca.adb, s-fileio.adb: Remove unused use-type
+	clauses from the runtime.
+
 2017-05-02  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* freeze.adb (Check_Component_Storage_Order): Do not treat bit-packed

gcc/ada/a-direio.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1992-2016, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2017, 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- --
@@ -39,12 +39,9 @@ with System;               use System;
 with System.CRTL;
 with System.File_Control_Block;
 with System.File_IO;
-with System.Direct_IO;
 with System.Storage_Elements;
 with Ada.Unchecked_Conversion;
 
-use type System.Direct_IO.Count;
-
 package body Ada.Direct_IO is
 
    Zeroes : constant System.Storage_Elements.Storage_Array :=

gcc/ada/a-exetim-posix.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---         Copyright (C) 2007-2015, Free Software Foundation, Inc.          --
+--         Copyright (C) 2007-2017, 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- --
@@ -164,7 +164,7 @@ package body Ada.Execution_Time is
       SC : out Ada.Real_Time.Seconds_Count;
       TS : out Ada.Real_Time.Time_Span)
    is
-      use type Ada.Real_Time.Time;
+
    begin
       Ada.Real_Time.Split (Ada.Real_Time.Time (T), SC, TS);
    end Split;

gcc/ada/checks.adb

@@ -4037,7 +4037,10 @@ package body Checks is
    -- Null_Exclusion_Static_Checks --
    ----------------------------------
 
-   procedure Null_Exclusion_Static_Checks (N : Node_Id) is
+   procedure Null_Exclusion_Static_Checks
+     (N    : Node_Id;
+      Comp : Node_Id := Empty)
+   is
       Error_Node : Node_Id;
       Expr       : Node_Id;
       Has_Null   : constant Boolean := Has_Null_Exclusion (N);
@@ -4119,11 +4122,27 @@ package body Checks is
          Set_Expression (N, Make_Null (Sloc (N)));
          Set_Etype (Expression (N), Etype (Defining_Identifier (N)));
 
-         Apply_Compile_Time_Constraint_Error
-           (N      => Expression (N),
-            Msg    =>
-              "(Ada 2005) null-excluding objects must be initialized??",
-            Reason => CE_Null_Not_Allowed);
+         if Present (Comp) then
+
+            --  Specialize the error message to indicate that we are dealing
+            --  with an uninitialized composite object that has a defaulted
+            --  null-excluding component.
+
+            Error_Msg_Name_1 := Chars (Defining_Identifier (Comp));
+            Error_Msg_Name_2 := Chars (Defining_Identifier (N));
+
+            Apply_Compile_Time_Constraint_Error
+              (N      => Expression (N),
+               Msg    => "(Ada 2005) null-excluding component % of object % " &
+                           "must be initialized??",
+               Reason => CE_Null_Not_Allowed);
+         else
+            Apply_Compile_Time_Constraint_Error
+              (N      => Expression (N),
+               Msg    =>
+                 "(Ada 2005) null-excluding objects must be initialized??",
+               Reason => CE_Null_Not_Allowed);
+         end if;
       end if;
 
       --  Check that a null-excluding component, formal or object is not being

gcc/ada/checks.ads

@@ -915,8 +915,14 @@ package Checks is
    --  Chars (Related_Id)_FIRST/_LAST. For suggested use of these parameters
    --  see the warning in the body of Sem_Ch3.Process_Range_Expr_In_Decl.
 
-   procedure Null_Exclusion_Static_Checks (N : Node_Id);
+   procedure Null_Exclusion_Static_Checks
+     (N    : Node_Id;
+      Comp : Node_Id := Empty);
    --  Ada 2005 (AI-231): Check bad usages of the null-exclusion issue
+   --
+   --  When a value for Comp is supplied (as in the case of an uninitialized
+   --  null-excluding component within a composite object), a reported error
+   --  will indicate the offending component instead of the object itself.
 
    procedure Remove_Checks (Expr : Node_Id);
    --  Remove all checks from Expr except those that are only executed

gcc/ada/g-socket.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---                     Copyright (C) 2001-2016, AdaCore                     --
+--                     Copyright (C) 2001-2017, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -2633,8 +2633,6 @@ package body GNAT.Sockets is
    ----------------------
 
    function To_Service_Entry (E : Servent_Access) return Service_Entry_Type is
-      use type C.size_t;
-
       Aliases_Count : Natural;
 
    begin

gcc/ada/s-fileio.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---          Copyright (C) 1992-2016, Free Software Foundation, Inc.         --
+--          Copyright (C) 1992-2017, 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- --
@@ -33,7 +33,6 @@ with Ada.Finalization;           use Ada.Finalization;
 with Ada.IO_Exceptions;          use Ada.IO_Exceptions;
 with Ada.Unchecked_Deallocation;
 
-with Interfaces.C;
 with Interfaces.C_Streams;       use Interfaces.C_Streams;
 
 with System.Case_Util;           use System.Case_Util;
@@ -48,7 +47,6 @@ package body System.File_IO is
    package SSL renames System.Soft_Links;
 
    use type CRTL.size_t;
-   use type Interfaces.C.int;
 
    ----------------------
    -- Global Variables --

gcc/ada/s-mudido-affinity.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---          Copyright (C) 2011-2015, Free Software Foundation, Inc.         --
+--          Copyright (C) 2011-2017, Free Software Foundation, Inc.         --
 --                                                                          --
 -- GNARL 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- --
@@ -77,8 +77,6 @@ package body System.Multiprocessors.Dispatching_Domains is
    is
       Target : constant ST.Task_Id := Convert_Ids (T);
 
-      use type ST.Dispatching_Domain_Access;
-
    begin
       --  The exception Dispatching_Domain_Error is propagated if T is already
       --  assigned to a Dispatching_Domain other than
@@ -127,7 +125,6 @@ package body System.Multiprocessors.Dispatching_Domains is
 
       use type ST.Dispatching_Domain;
       use type ST.Dispatching_Domain_Access;
-      use type ST.Array_Allocated_Tasks;
       use type ST.Task_Id;
 
       T : ST.Task_Id;
@@ -331,8 +328,6 @@ package body System.Multiprocessors.Dispatching_Domains is
    is
       Target : constant ST.Task_Id := Convert_Ids (T);
 
-      use type ST.Dispatching_Domain_Access;
-
    begin
       --  The exception Dispatching_Domain_Error is propagated if CPU is not
       --  one of the processors of the Dispatching_Domain on which T is

gcc/ada/s-taenca.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---         Copyright (C) 1992-2011, Free Software Foundation, Inc.          --
+--         Copyright (C) 1992-2017, Free Software Foundation, Inc.          --
 --                                                                          --
 -- GNARL 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- --
@@ -533,8 +533,6 @@ package body System.Tasking.Entry_Calls is
       Self_Id  : constant Task_Id := Entry_Call.Self;
       Timedout : Boolean := False;
 
-      use type Ada.Exceptions.Exception_Id;
-
    begin
       --  This procedure waits for the entry call to be served, with a timeout.
       --  It tries to cancel the call if the timeout expires before the call is

gcc/ada/s-taprop-linux.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---         Copyright (C) 1992-2016, Free Software Foundation, Inc.          --
+--         Copyright (C) 1992-2017, Free Software Foundation, Inc.          --
 --                                                                          --
 -- GNARL 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- --
@@ -1525,8 +1525,6 @@ package body System.Task_Primitives.Operations is
       --    's'   Interrupt_State pragma set state to System (use "default"
       --           system handler)
 
-      use type System.Multiprocessors.CPU_Range;
-
    begin
       Environment_Task_Id := Environment_Task;
 

gcc/ada/s-tasini.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                  B o d y                                 --
 --                                                                          --
---         Copyright (C) 1992-2016, Free Software Foundation, Inc.          --
+--         Copyright (C) 1992-2017, Free Software Foundation, Inc.          --
 --                                                                          --
 -- GNARL 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- --
@@ -38,8 +38,6 @@ pragma Polling (Off);
 --  routines in this package, and more to the point, if we try to poll it can
 --  cause infinite loops.
 
-with Ada.Exceptions;
-
 with System.Task_Primitives;
 with System.Task_Primitives.Operations;
 with System.Soft_Links;
@@ -234,7 +232,6 @@ package body System.Tasking.Initialization is
    --  Call only when holding no locks
 
    procedure Do_Pending_Action (Self_ID : Task_Id) is
-      use type Ada.Exceptions.Exception_Id;
 
    begin
       pragma Assert (Self_ID = Self and then Self_ID.Deferral_Level = 0);

gcc/ada/s-tasren.adb

@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---         Copyright (C) 1992-2014, Free Software Foundation, Inc.          --
+--         Copyright (C) 1992-2017, Free Software Foundation, Inc.          --
 --                                                                          --
 -- GNARL 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- --
@@ -547,8 +547,6 @@ package body System.Tasking.Rendezvous is
          Source : Ada.Exceptions.Exception_Occurrence);
       pragma Import (C, Transfer_Occurrence, "__gnat_transfer_occurrence");
 
-      use type STPE.Protection_Entries_Access;
-
    begin
       --  The deferral level is critical here, since we want to raise an
       --  exception or allow abort to take place, if there is an exception or

gcc/ada/sem_ch10.adb

@@ -2288,10 +2288,10 @@ package body Sem_Ch10 is
          Pop_Scope;
       end Remove_Scope;
 
-      Saved_SM  : constant SPARK_Mode_Type := SPARK_Mode;
-      Saved_SMP : constant Node_Id         := SPARK_Mode_Pragma;
+      Saved_SM  : SPARK_Mode_Type := SPARK_Mode;
+      Saved_SMP : Node_Id         := SPARK_Mode_Pragma;
       --  Save the SPARK mode-related data to restore on exit. Removing
-      --  eclosing scopes and contexts to provide a clean environment for the
+      --  enclosing scopes and contexts to provide a clean environment for the
       --  context of the subunit will eliminate any previously set SPARK_Mode.
 
    --  Start of processing for Analyze_Subunit
@@ -2351,6 +2351,15 @@ package body Sem_Ch10 is
 
          Analyze_Subunit_Context;
 
+         --  Take into account the effect of any SPARK_Mode configuration
+         --  pragma, which takes precedence over a different value of
+         --  SPARK_Mode inherited from the context of the stub.
+
+         if SPARK_Mode /= None then
+            Saved_SM  := SPARK_Mode;
+            Saved_SMP := SPARK_Mode_Pragma;
+         end if;
+
          Re_Install_Parents (Lib_Unit, Par_Unit);
          Set_Is_Immediately_Visible (Par_Unit);
 
@@ -2392,7 +2401,8 @@ package body Sem_Ch10 is
       Generate_Parent_References (Unit (N), Par_Unit);
 
       --  Reinstall the SPARK_Mode which was in effect prior to any scope and
-      --  context manipulations.
+      --  context manipulations, taking into account a possible SPARK_Mode
+      --  configuration pragma if present.
 
       Install_SPARK_Mode (Saved_SM, Saved_SMP);
 

gcc/ada/sem_ch3.adb

@@ -3588,6 +3588,13 @@ package body Sem_Ch3 is
 
       Prev_Entity : Entity_Id := Empty;
 
+      procedure Check_For_Null_Excluding_Components
+        (Obj_Typ  : Entity_Id;
+         Obj_Decl : Node_Id);
+      --  Recursively verify that each null-excluding component of an object
+      --  declaration's type has explicit initialization, and generate
+      --  compile-time warnings for each one that does not.
+
       function Count_Tasks (T : Entity_Id) return Uint;
       --  This function is called when a non-generic library level object of a
       --  task type is declared. Its function is to count the static number of
@@ -3607,6 +3614,100 @@ package body Sem_Ch3 is
 
       --  Any other relevant delayed aspects on object declarations ???
 
+      -----------------------------------------
+      -- Check_For_Null_Excluding_Components --
+      -----------------------------------------
+
+      procedure Check_For_Null_Excluding_Components
+        (Obj_Typ  : Entity_Id;
+         Obj_Decl : Node_Id)
+      is
+
+         procedure Check_Component
+           (Comp_Typ  : Entity_Id;
+            Comp_Decl : Node_Id := Empty);
+         --  Perform compile-time null-exclusion checks on a given component
+         --  and all of its subcomponents, if any.
+
+         ---------------------
+         -- Check_Component --
+         ---------------------
+
+         procedure Check_Component
+           (Comp_Typ  : Entity_Id;
+            Comp_Decl : Node_Id := Empty)
+         is
+            Comp : Entity_Id;
+            T    : Entity_Id;
+
+         begin
+            --  Return without further checking if the component has explicit
+            --  initialization or does not come from source.
+
+            if Present (Comp_Decl) then
+               if not Comes_From_Source (Comp_Decl)
+                 or else Present (Expression (Comp_Decl))
+               then
+                  return;
+               end if;
+            end if;
+
+            if Is_Incomplete_Or_Private_Type (Comp_Typ)
+              and then Present (Full_View (Comp_Typ))
+            then
+               T := Full_View (Comp_Typ);
+            else
+               T := Comp_Typ;
+            end if;
+
+            --  Verify a component of a null-excluding access type
+
+            if Is_Access_Type (T)
+              and then Can_Never_Be_Null (T)
+            then
+               Null_Exclusion_Static_Checks (Obj_Decl, Comp_Decl);
+
+            --  Check array type components
+
+            elsif Is_Array_Type (T) then
+               --  There is no suitable component when the object is of an
+               --  array type. However, a namable component may appear at some
+               --  point during the recursive inspection, but not at the top
+               --  level.
+
+               if Comp_Decl = Obj_Decl then
+                  Check_Component (Component_Type (T));
+               else
+                  Check_Component (Component_Type (T), Comp_Decl);
+               end if;
+
+            --  If T allows named components, then iterate through them,
+            --  recursively verifying all subcomponents.
+
+            --  NOTE: Due to the complexities involved with checking components
+            --  of nontrivial types with discriminants (variant records and
+            --  the like), no static checking is performed on them. ???
+
+            elsif (Is_Concurrent_Type (T)
+                    or else Is_Incomplete_Or_Private_Type (T)
+                    or else Is_Record_Type (T))
+               and then not Has_Discriminants (T)
+            then
+               Comp := First_Component (T);
+               while Present (Comp) loop
+                  Check_Component (Etype (Comp), Parent (Comp));
+
+                  Comp := Next_Component (Comp);
+               end loop;
+            end if;
+         end Check_Component;
+
+      --  Start processing for Check_For_Null_Excluding_Components
+
+      begin
+         Check_Component (Obj_Typ, Obj_Decl);
+      end Check_For_Null_Excluding_Components;
+
       -----------------
       -- Count_Tasks --
       -----------------
@@ -3808,25 +3909,34 @@ package body Sem_Ch3 is
       --  Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
       --  out some static checks.
 
-      if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
-
+      if Ada_Version >= Ada_2005 then
          --  In case of aggregates we must also take care of the correct
          --  initialization of nested aggregates bug this is done at the
          --  point of the analysis of the aggregate (see sem_aggr.adb) ???
 
-         if Present (Expression (N))
-           and then Nkind (Expression (N)) = N_Aggregate
-         then
-            null;
+         if Can_Never_Be_Null (T) then
+
+            if Present (Expression (N))
+              and then Nkind (Expression (N)) = N_Aggregate
+            then
+               null;
+
+            else
+               declare
+                  Save_Typ : constant Entity_Id := Etype (Id);
+               begin
+                  Set_Etype (Id, T); --  Temp. decoration for static checks
+                  Null_Exclusion_Static_Checks (N);
+                  Set_Etype (Id, Save_Typ);
+               end;
+            end if;
+
+         --  We might be dealing with an object of a composite type containing
+         --  null-excluding components without an aggregate, so we must verify
+         --  that such components have default initialization.
 
          else
-            declare
-               Save_Typ : constant Entity_Id := Etype (Id);
-            begin
-               Set_Etype (Id, T); --  Temp. decoration for static checks
-               Null_Exclusion_Static_Checks (N);
-               Set_Etype (Id, Save_Typ);
-            end;
+            Check_For_Null_Excluding_Components (T, N);
          end if;
       end if;
 

gcc/ada/sem_ch6.adb

@@ -8770,6 +8770,16 @@ package body Sem_Ch6 is
                         and then Ekind (Entity (E1)) = E_Discriminant
                         and then Ekind (Entity (E2)) = E_In_Parameter)
 
+             --  The discriminant of a protected type is transformed into
+             --  a local constant and then into a parameter of a protected
+             --  operation.
+
+             or else (Ekind (Entity (E1)) = E_Constant
+                 and then Ekind (Entity (E2)) = E_In_Parameter
+                 and then Present (Discriminal_Link (Entity (E1)))
+                 and then Discriminal_Link (Entity (E1)) =
+                          Discriminal_Link (Entity (E2)))
+
              --  AI12-050: The loop variables of quantified expressions
              --  match if they have the same identifier, even though they
              --  are different entities.