opt.ads: Elaboration warnings are now on by default.

2017-11-16  Hristian Kirtchev  <kirtchev@adacore.com>

	* opt.ads: Elaboration warnings are now on by default. Add a comment
	explaining why this is needed.
	* sem_ch9.adb (Analyze_Requeue): Preserve the status of elaboration
	warnings.
	* sem_ch12.adb (Analyze_Package_Instantiation): Preserve the status of
	elaboration warnings.
	(Analyze_Subprogram_Instantiation): Preserve the status of elaboration
	warnings.
	* sem_elab.adb: Update the structure of Call_Attributes and
	Instantiation_Attributes.
	(Build_Call_Marker): Propagate the status of elaboration warnings from
	the call to the marker.
	(Extract_Call_Attributes): Extract the status of elaboration warnings.
	(Extract_Instantiation_Attributes): Extract the status of elaboration
	warnings.
	(Process_Conditional_ABE_Activation_Impl): Elaboration diagnostics are
	now dependent on the status of elaboration warnings.
	(Process_Conditional_ABE_Call_Ada): Elaboration diagnostics are now
	dependent on the status of elaboration warnings.
	(Process_Conditional_ABE_Instantiation_Ada): Elaboration diagnostics
	are now dependent on the status of elaboration warnings.
	(Process_Guaranteed_ABE_Activation_Impl): Remove pragma Unreferenced
	for formal Call_Attrs. Elaboration diagnostics are now dependent on the
	status of elaboration warnings.
	(Process_Guaranteed_ABE_Call): Elaboration diagnostics are now
	dependent on the status of elaboration warnings.
	(Process_Guaranteed_ABE_Instantiation): Elaboration diagnostics are now
	dependent on the status of elaboration warnings.
	* sem_prag.adb (Analyze_Pragma): Remove the unjustified warning
	concerning pragma Elaborate.
	* sem_res.adb (Resolve_Call): Preserve the status of elaboration
	warnings.
	(Resolve_Entry_Call): Propagate flag Is_Elaboration_Warnings_OK_Node
	from the procedure call to the entry call.
	* sem_util.adb (Mark_Elaboration_Attributes): Add formal parameter
	Warnings.
	(Mark_Elaboration_Attributes_Node): Preserve the status of elaboration
	warnings
	* sem_util.ads (Mark_Elaboration_Attributes): Add formal parameter
	Warnings. Update the comment on usage.
	* sinfo.adb (Is_Dispatching_Call): Update to use Flag6.
	(Is_Elaboration_Warnings_OK_Node): New routine.
	(Set_Is_Dispatching_Call): Update to use Flag6.
	(Set_Is_Elaboration_Warnings_OK_Node): New routine.
	* sinfo.ads: Attribute Is_Dispatching_Call now uses Flag6. Add new
	attribute Is_Elaboration_Warnings_OK_Node along with occurrences
	in nodes.
	(Is_Elaboration_Warnings_OK_Node): New routine along with pragma
	Inline.
	(Set_Is_Elaboration_Warnings_OK_Node): New routine along with pragma
	Inline.
	* doc/gnat_ugn/elaboration_order_handling_in_gnat.rst: Update various
	sections to indicate how to suppress elaboration warnings.  Document
	switches -gnatwl and -gnatwL.
	* gnat_ugn.texi: Regenerate.

From-SVN: r254819

13 files changed, 355 insertions, 109 deletions

diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 1f3cf29..26457f1 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,61 @@
+2017-11-16  Hristian Kirtchev  <kirtchev@adacore.com>
+
+	* opt.ads: Elaboration warnings are now on by default. Add a comment
+	explaining why this is needed.
+	* sem_ch9.adb (Analyze_Requeue): Preserve the status of elaboration
+	warnings.
+	* sem_ch12.adb (Analyze_Package_Instantiation): Preserve the status of
+	elaboration warnings.
+	(Analyze_Subprogram_Instantiation): Preserve the status of elaboration
+	warnings.
+	* sem_elab.adb: Update the structure of Call_Attributes and
+	Instantiation_Attributes.
+	(Build_Call_Marker): Propagate the status of elaboration warnings from
+	the call to the marker.
+	(Extract_Call_Attributes): Extract the status of elaboration warnings.
+	(Extract_Instantiation_Attributes): Extract the status of elaboration
+	warnings.
+	(Process_Conditional_ABE_Activation_Impl): Elaboration diagnostics are
+	now dependent on the status of elaboration warnings.
+	(Process_Conditional_ABE_Call_Ada): Elaboration diagnostics are now
+	dependent on the status of elaboration warnings.
+	(Process_Conditional_ABE_Instantiation_Ada): Elaboration diagnostics
+	are now dependent on the status of elaboration warnings.
+	(Process_Guaranteed_ABE_Activation_Impl): Remove pragma Unreferenced
+	for formal Call_Attrs. Elaboration diagnostics are now dependent on the
+	status of elaboration warnings.
+	(Process_Guaranteed_ABE_Call): Elaboration diagnostics are now
+	dependent on the status of elaboration warnings.
+	(Process_Guaranteed_ABE_Instantiation): Elaboration diagnostics are now
+	dependent on the status of elaboration warnings.
+	* sem_prag.adb (Analyze_Pragma): Remove the unjustified warning
+	concerning pragma Elaborate.
+	* sem_res.adb (Resolve_Call): Preserve the status of elaboration
+	warnings.
+	(Resolve_Entry_Call): Propagate flag Is_Elaboration_Warnings_OK_Node
+	from the procedure call to the entry call.
+	* sem_util.adb (Mark_Elaboration_Attributes): Add formal parameter
+	Warnings.
+	(Mark_Elaboration_Attributes_Node): Preserve the status of elaboration
+	warnings
+	* sem_util.ads (Mark_Elaboration_Attributes): Add formal parameter
+	Warnings. Update the comment on usage.
+	* sinfo.adb (Is_Dispatching_Call): Update to use Flag6.
+	(Is_Elaboration_Warnings_OK_Node): New routine.
+	(Set_Is_Dispatching_Call): Update to use Flag6.
+	(Set_Is_Elaboration_Warnings_OK_Node): New routine.
+	* sinfo.ads: Attribute Is_Dispatching_Call now uses Flag6. Add new
+	attribute Is_Elaboration_Warnings_OK_Node along with occurrences
+	in nodes.
+	(Is_Elaboration_Warnings_OK_Node): New routine along with pragma
+	Inline.
+	(Set_Is_Elaboration_Warnings_OK_Node): New routine along with pragma
+	Inline.
+	* doc/gnat_ugn/elaboration_order_handling_in_gnat.rst: Update various
+	sections to indicate how to suppress elaboration warnings.  Document
+	switches -gnatwl and -gnatwL.
+	* gnat_ugn.texi: Regenerate.
+
 2017-11-16  Sylvain Dailler  <dailler@adacore.com>
 
 	* sem_util.adb (Get_Enum_Lit_From_Pos): Add a condition for Pos
diff --git a/gcc/ada/doc/gnat_ugn/elaboration_order_handling_in_gnat.rst b/gcc/ada/doc/gnat_ugn/elaboration_order_handling_in_gnat.rst
index c45d3fc..57acf53 100644
--- a/gcc/ada/doc/gnat_ugn/elaboration_order_handling_in_gnat.rst
+++ b/gcc/ada/doc/gnat_ugn/elaboration_order_handling_in_gnat.rst
@@ -690,8 +690,8 @@ dispatching calls and a particular kind of ABE referred to as *guaranteed ABE*.
 Note that GNAT emits warnings rather than hard errors whenever it encounters an
 elaboration problem. This is because the elaboration model in effect may be too
 conservative, or a particular scenario may not be elaborated or executed due to
-data and control flow. The warnings can be suppressed with compiler switch
-:switch:`-gnatws`.
+data and control flow. The warnings can be suppressed selectively with ``pragma
+Warnigns (Off)`` or globally with compiler switch :switch:`-gnatwL`.
 
 .. _Dynamic_Elaboration_Model_in_GNAT:
 
@@ -764,8 +764,8 @@ run-time checks based on the nature of the target.
 
   The static model performs extensive diagnostics on scenarios which elaborate
   or execute internal targets. The warnings resulting from these diagnostics
-  are enabled by default, but can be suppressed using compiler switch
-  :switch:`-gnatws`.
+  are enabled by default, but can be suppressed selectively with ``pragma
+  Warnings (Off)`` or globally with compiler switch :switch:`-gnatwL`.
 
   ::
 
@@ -1648,6 +1648,47 @@ the elaboration order chosen by the binder.
   In the example above, the elaboration of declaration ``Ptr`` is assigned
   ``Func'Access`` before the body of ``Func`` has been elaborated.
 
+.. index:: -gnatwl  (gnat)
+
+:switch:`-gnatwl`
+  Turn on warnings for elaboration problems
+
+  When this switch is in effect, GNAT emits diagnostics in the form of warnings
+  concerning various elaboration problems. The warnings are enabled by default.
+  The switch is provided in case all warnings are suppressed, but elaboration
+  warnings are still desired.
+
+:switch:`-gnatwL`
+  Turn off warnings for elaboration problems
+
+  When this switch is in effect, GNAT no longer emits any diagnostics in the
+  form of warnings. Selective suppression of elaboration problems is possible
+  using ``pragma Warnings (Off)``.
+
+  ::
+
+     1. package body Selective_Suppression is
+     2.    function ABE return Integer;
+     3.
+     4.    Val_1 : constant Integer := ABE;
+                                       |
+        >>> warning: cannot call "ABE" before body seen
+        >>> warning: Program_Error will be raised at run time
+
+     5.
+     6.    pragma Warnings (Off);
+     7.    Val_2 : constant Integer := ABE;
+     8.    pragma Warnings (On);
+     9.
+    10.    function ABE return Integer is
+    11.    begin
+    12.       ...
+    13.    end ABE;
+    14. end Selective_Suppression;
+
+  Note that suppressing elaboration warnings does not eliminate run-time
+  checks. The example above will still fail at runtime with an ABE.
+
 .. _Summary_of_Procedures_for_Elaboration_Control:
 
 Summary of Procedures for Elaboration Control
diff --git a/gcc/ada/gnat_ugn.texi b/gcc/ada/gnat_ugn.texi
index 05fdf4c..43ef245 100644
--- a/gcc/ada/gnat_ugn.texi
+++ b/gcc/ada/gnat_ugn.texi
@@ -21,7 +21,7 @@
 
 @copying
 @quotation
-GNAT User's Guide for Native Platforms , Nov 09, 2017
+GNAT User's Guide for Native Platforms , Nov 16, 2017
 
 AdaCore
 
@@ -27897,8 +27897,8 @@ three models:
 Note that GNAT emits warnings rather than hard errors whenever it encounters an
 elaboration problem. This is because the elaboration model in effect may be too
 conservative, or a particular scenario may not be elaborated or executed due to
-data and control flow. The warnings can be suppressed with compiler switch
-@code{-gnatws}.
+data and control flow. The warnings can be suppressed selectively with @code{pragma
+Warnigns (Off)} or globally with compiler switch @code{-gnatwL}.
 
 @node Dynamic Elaboration Model in GNAT,Static Elaboration Model in GNAT,Common Elaboration-model Traits,Elaboration Order Handling in GNAT
 @anchor{gnat_ugn/elaboration_order_handling_in_gnat dynamic-elaboration-model-in-gnat}@anchor{23e}@anchor{gnat_ugn/elaboration_order_handling_in_gnat id8}@anchor{23f}
@@ -27975,8 +27975,8 @@ run-time checks based on the nature of the target.
 
 The static model performs extensive diagnostics on scenarios which elaborate
 or execute internal targets. The warnings resulting from these diagnostics
-are enabled by default, but can be suppressed using compiler switch
-@code{-gnatws}.
+are enabled by default, but can be suppressed selectively with @code{pragma
+Warnings (Off)} or globally with compiler switch @code{-gnatwL}.
 
 @example
  1. package body Static_Model is
@@ -28959,6 +28959,53 @@ In the example above, the elaboration of declaration @code{Ptr} is assigned
 @code{Func'Access} before the body of @code{Func} has been elaborated.
 @end table
 
+@geindex -gnatwl (gnat)
+
+
+@table @asis
+
+@item @code{-gnatwl}
+
+Turn on warnings for elaboration problems
+
+When this switch is in effect, GNAT emits diagnostics in the form of warnings
+concerning various elaboration problems. The warnings are enabled by default.
+The switch is provided in case all warnings are suppressed, but elaboration
+warnings are still desired.
+
+@item @code{-gnatwL}
+
+Turn off warnings for elaboration problems
+
+When this switch is in effect, GNAT no longer emits any diagnostics in the
+form of warnings. Selective suppression of elaboration problems is possible
+using @code{pragma Warnings (Off)}.
+
+@example
+ 1. package body Selective_Suppression is
+ 2.    function ABE return Integer;
+ 3.
+ 4.    Val_1 : constant Integer := ABE;
+                                   |
+    >>> warning: cannot call "ABE" before body seen
+    >>> warning: Program_Error will be raised at run time
+
+ 5.
+ 6.    pragma Warnings (Off);
+ 7.    Val_2 : constant Integer := ABE;
+ 8.    pragma Warnings (On);
+ 9.
+10.    function ABE return Integer is
+11.    begin
+12.       ...
+13.    end ABE;
+14. end Selective_Suppression;
+@end example
+
+Note that suppressing elaboration warnings does not eliminate run-time
+checks. The example above will still fail at runtime with an ABE.
+@end table
+
 @node Summary of Procedures for Elaboration Control,Inspecting the Chosen Elaboration Order,Elaboration-related Compiler Switches,Elaboration Order Handling in GNAT
 @anchor{gnat_ugn/elaboration_order_handling_in_gnat summary-of-procedures-for-elaboration-control}@anchor{24e}@anchor{gnat_ugn/elaboration_order_handling_in_gnat id16}@anchor{24f}
 @section Summary of Procedures for Elaboration Control
diff --git a/gcc/ada/opt.ads b/gcc/ada/opt.ads
index 94ed953..86a5c35 100644
--- a/gcc/ada/opt.ads
+++ b/gcc/ada/opt.ads
@@ -553,9 +553,13 @@ package Opt is
    --  GNAT
    --  Set to True to output info messages for static elabmodel (-gnatel)
 
-   Elab_Warnings : Boolean := False;
+   Elab_Warnings : Boolean := True;
    --  GNAT
-   --  Set to True to generate elaboration warnings (-gnatwl)
+   --  Set to True to generate elaboration warnings (-gnatwl). The warnings are
+   --  enabled by default because they carry the same importance as errors. The
+   --  compiler cannot emit actual errors because elaboration diagnostics need
+   --  dataflow analysis, which is not available. This behavior parallels that
+   --  of the old ABE mechanism.
 
    Error_Msg_Line_Length : Nat := 0;
    --  GNAT
diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
index 23f9ca7..afa58f4 100644
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -3943,10 +3943,11 @@ package body Sem_Ch12 is
       --  resolution, and expansion are over.
 
       Mark_Elaboration_Attributes
-        (N_Id   => N,
-         Checks => True,
-         Level  => True,
-         Modes  => True);
+        (N_Id     => N,
+         Checks   => True,
+         Level    => True,
+         Modes    => True,
+         Warnings => True);
 
       Check_SPARK_05_Restriction ("generic is not allowed", N);
 
@@ -5393,10 +5394,11 @@ package body Sem_Ch12 is
       --  resolution, and expansion are over.
 
       Mark_Elaboration_Attributes
-        (N_Id   => N,
-         Checks => True,
-         Level  => True,
-         Modes  => True);
+        (N_Id     => N,
+         Checks   => True,
+         Level    => True,
+         Modes    => True,
+         Warnings => True);
 
       Check_SPARK_05_Restriction ("generic is not allowed", N);
 
diff --git a/gcc/ada/sem_ch9.adb b/gcc/ada/sem_ch9.adb
index 7667422..e163135 100644
--- a/gcc/ada/sem_ch9.adb
+++ b/gcc/ada/sem_ch9.adb
@@ -2295,9 +2295,10 @@ package body Sem_Ch9 is
       --  resolution, and expansion are over.
 
       Mark_Elaboration_Attributes
-        (N_Id   => N,
-         Checks => True,
-         Modes  => True);
+        (N_Id     => N,
+         Checks   => True,
+         Modes    => True,
+         Warnings => True);
 
       Tasking_Used := True;
       Check_SPARK_05_Restriction ("requeue statement is not allowed", N);
diff --git a/gcc/ada/sem_elab.adb b/gcc/ada/sem_elab.adb
index 1f85494..b34523f 100644
--- a/gcc/ada/sem_elab.adb
+++ b/gcc/ada/sem_elab.adb
@@ -444,15 +444,6 @@ package body Sem_Elab is
    --
    --           The complimentary switch for -gnatel.
    --
-   --  -gnatwl  turn on warnings for elaboration problems
-   --
-   --           The ABE mechanism produces warnings on detected ABEs along with
-   --           traceback showing the graph of the ABE.
-   --
-   --  -gnatwL  turn off warnings for elaboration problems
-   --
-   --           The complimentary switch for -gnatwl.
-   --
    --  -gnatw.f turn on warnings for suspicious Subp'Access
    --
    --           The ABE mechanism treats '[Unrestricted_]Access of an entry,
@@ -462,6 +453,15 @@ package body Sem_Elab is
    --  -gnatw.F turn off warnings for suspicious Subp'Access
    --
    --           The complimentary switch for -gnatw.f.
+   --
+   --  -gnatwl  turn on warnings for elaboration problems
+   --
+   --           The ABE mechanism produces warnings on detected ABEs along with
+   --           traceback showing the graph of the ABE.
+   --
+   --  -gnatwL  turn off warnings for elaboration problems
+   --
+   --           The complimentary switch for -gnatwl.
 
    ---------------------------
    -- Adding a new scenario --
@@ -567,6 +567,9 @@ package body Sem_Elab is
       Elab_Checks_OK : Boolean;
       --  This flag is set when the call has elaboration checks enabled
 
+      Elab_Warnings_OK : Boolean;
+      --  This flag is set when the call has elaboration warnings elabled
+
       From_Source : Boolean;
       --  This flag is set when the call comes from source
 
@@ -622,6 +625,10 @@ package body Sem_Elab is
       --  This flag is set when the instantiation has elaboration checks
       --  enabled.
 
+      Elab_Warnings_OK : Boolean;
+      --  This flag is set when the instantiation has elaboration warnings
+      --  enabled.
+
       Ghost_Mode_Ignore : Boolean;
       --  This flag is set when the instantiation appears in a region subject
       --  to pragma Ghost with policy ignore, or starts one such region.
@@ -1519,7 +1526,7 @@ package body Sem_Elab is
       In_Partial_Fin : Boolean;
       In_Task_Body   : Boolean);
    --  Perform common conditional ABE checks and diagnostics for call Call
-   --  which activates task Obj_Id ignoring the Ada or SPARK rules. CAll_Attrs
+   --  which activates task Obj_Id ignoring the Ada or SPARK rules. Call_Attrs
    --  are the attributes of the activation call. Task_Attrs are the attributes
    --  of the task type. The flags should be set when the processing was
    --  initiated as follows:
@@ -1657,11 +1664,11 @@ package body Sem_Elab is
       In_Partial_Fin : Boolean;
       In_Task_Body   : Boolean);
    --  Perform common guaranteed ABE checks and diagnostics for call Call which
-   --  activates task Obj_Id ignoring the Ada or SPARK rules. Task_Attrs are
-   --  the attributes of the task type. The following parameters are provided
-   --  for compatibility and are unused.
+   --  activates task Obj_Id ignoring the Ada or SPARK rules. Call_Attrs are
+   --  the attributes of the activation call. Task_Attrs are the attributes of
+   --  the task type. The following parameters are provided for compatibility
+   --  and are not used.
    --
-   --    Call_Attrs
    --    In_Init_Cond
    --    In_Partial_Fin
    --    In_Task_Body
@@ -2057,13 +2064,16 @@ package body Sem_Elab is
 
       --  Inherit the attributes of the original call
 
-      Set_Target                        (Marker, Target_Id);
-      Set_Is_Elaboration_Checks_OK_Node (Marker, Call_Attrs.Elab_Checks_OK);
-      Set_Is_Declaration_Level_Node     (Marker, Call_Attrs.In_Declarations);
-      Set_Is_Dispatching_Call           (Marker, Call_Attrs.Is_Dispatching);
-      Set_Is_Ignored_Ghost_Node         (Marker, Call_Attrs.Ghost_Mode_Ignore);
-      Set_Is_Source_Call                (Marker, Call_Attrs.From_Source);
-      Set_Is_SPARK_Mode_On_Node         (Marker, Call_Attrs.SPARK_Mode_On);
+      Set_Target                    (Marker, Target_Id);
+      Set_Is_Declaration_Level_Node (Marker, Call_Attrs.In_Declarations);
+      Set_Is_Dispatching_Call       (Marker, Call_Attrs.Is_Dispatching);
+      Set_Is_Elaboration_Checks_OK_Node
+                                    (Marker, Call_Attrs.Elab_Checks_OK);
+      Set_Is_Elaboration_Warnings_OK_Node
+                                    (Marker, Call_Attrs.Elab_Warnings_OK);
+      Set_Is_Ignored_Ghost_Node     (Marker, Call_Attrs.Ghost_Mode_Ignore);
+      Set_Is_Source_Call            (Marker, Call_Attrs.From_Source);
+      Set_Is_SPARK_Mode_On_Node     (Marker, Call_Attrs.SPARK_Mode_On);
 
       --  The marker is inserted prior to the original call. This placement has
       --  several desirable effects:
@@ -3567,6 +3577,7 @@ package body Sem_Elab is
       --  Set all attributes
 
       Attrs.Elab_Checks_OK    := Is_Elaboration_Checks_OK_Node (Call);
+      Attrs.Elab_Warnings_OK  := Is_Elaboration_Warnings_OK_Node (Call);
       Attrs.From_Source       := From_Source;
       Attrs.Ghost_Mode_Ignore := Is_Ignored_Ghost_Node (Call);
       Attrs.In_Declarations   := In_Declarations;
@@ -3653,8 +3664,8 @@ package body Sem_Elab is
       Attrs    : out Instantiation_Attributes)
    is
    begin
-      Inst     := Original_Node (Exp_Inst);
-      Inst_Id  := Defining_Entity (Inst);
+      Inst    := Original_Node (Exp_Inst);
+      Inst_Id := Defining_Entity (Inst);
 
       --  Traverse a possible chain of renamings to obtain the original generic
       --  being instantiatied.
@@ -3664,6 +3675,7 @@ package body Sem_Elab is
       --  Set all attributes
 
       Attrs.Elab_Checks_OK    := Is_Elaboration_Checks_OK_Node (Inst);
+      Attrs.Elab_Warnings_OK  := Is_Elaboration_Warnings_OK_Node (Inst);
       Attrs.Ghost_Mode_Ignore := Is_Ignored_Ghost_Node (Inst);
       Attrs.In_Declarations   := Is_Declaration_Level_Node (Inst);
       Attrs.SPARK_Mode_On     := Is_SPARK_Mode_On_Node (Inst);
@@ -8679,7 +8691,9 @@ package body Sem_Elab is
             --  this order diagnostics appear jumbled and result in unwanted
             --  noise.
 
-            elsif Static_Elaboration_Checks then
+            elsif Static_Elaboration_Checks
+              and then Call_Attrs.Elab_Warnings_OK
+            then
                Error_Msg_Sloc := Sloc (Call);
                Error_Msg_N
                  ("??task & will be activated # before elaboration of its "
@@ -9068,7 +9082,9 @@ package body Sem_Elab is
             --  this order diagnostics appear jumbled and result in unwanted
             --  noise.
 
-            elsif Static_Elaboration_Checks then
+            elsif Static_Elaboration_Checks
+              and then Call_Attrs.Elab_Warnings_OK
+            then
                Error_Msg_NE
                  ("??cannot call & before body seen", Call, Target_Id);
                Error_Msg_N ("\Program_Error may be raised at run time", Call);
@@ -9500,7 +9516,9 @@ package body Sem_Elab is
             --  this order diagnostics appear jumbled and result in unwanted
             --  noise.
 
-            elsif Static_Elaboration_Checks then
+            elsif Static_Elaboration_Checks
+              and then Inst_Attrs.Elab_Warnings_OK
+            then
                Error_Msg_NE
                  ("??cannot instantiate & before body seen", Inst, Gen_Id);
                Error_Msg_N ("\Program_Error may be raised at run time", Inst);
@@ -9668,10 +9686,6 @@ package body Sem_Elab is
         and then not Is_Initialized (Var_Decl)
         and then not Has_Pragma_Elaborate_Body (Spec_Id)
       then
-         --  Generate an implicit Elaborate_Body in the spec
-
-         Set_Elaborate_Body_Desirable (Spec_Id);
-
          Error_Msg_NE
            ("??variable & can be accessed by clients before this "
             & "initialization", Asmt, Var_Id);
@@ -9681,6 +9695,10 @@ package body Sem_Elab is
             & "initialization", Asmt, Spec_Id);
 
          Output_Active_Scenarios (Asmt);
+
+         --  Generate an implicit Elaborate_Body in the spec
+
+         Set_Elaborate_Body_Desirable (Spec_Id);
       end if;
    end Process_Conditional_ABE_Variable_Assignment_Ada;
 
@@ -9905,7 +9923,6 @@ package body Sem_Elab is
       In_Partial_Fin : Boolean;
       In_Task_Body   : Boolean)
    is
-      pragma Unreferenced (Call_Attrs);
       pragma Unreferenced (In_Init_Cond);
       pragma Unreferenced (In_Partial_Fin);
       pragma Unreferenced (In_Task_Body);
@@ -10017,11 +10034,13 @@ package body Sem_Elab is
                Target_Decl => Task_Attrs.Task_Decl,
                Target_Body => Task_Attrs.Body_Decl)
       then
-         Error_Msg_Sloc := Sloc (Call);
-         Error_Msg_N
-           ("??task & will be activated # before elaboration of its body",
-            Obj_Id);
-         Error_Msg_N ("\Program_Error will be raised at run time", Obj_Id);
+         if Call_Attrs.Elab_Warnings_OK then
+            Error_Msg_Sloc := Sloc (Call);
+            Error_Msg_N
+              ("??task & will be activated # before elaboration of its body",
+               Obj_Id);
+            Error_Msg_N ("\Program_Error will be raised at run time", Obj_Id);
+         end if;
 
          --  Mark the activation call as a guaranteed ABE
 
@@ -10130,8 +10149,10 @@ package body Sem_Elab is
                Target_Decl => Target_Attrs.Spec_Decl,
                Target_Body => Target_Attrs.Body_Decl)
       then
-         Error_Msg_NE ("??cannot call & before body seen", Call, Target_Id);
-         Error_Msg_N ("\Program_Error will be raised at run time", Call);
+         if Call_Attrs.Elab_Warnings_OK then
+            Error_Msg_NE ("??cannot call & before body seen", Call, Target_Id);
+            Error_Msg_N ("\Program_Error will be raised at run time", Call);
+         end if;
 
          --  Mark the call as a guarnateed ABE
 
@@ -10253,9 +10274,11 @@ package body Sem_Elab is
                Target_Decl => Gen_Attrs.Spec_Decl,
                Target_Body => Gen_Attrs.Body_Decl)
       then
-         Error_Msg_NE
-           ("??cannot instantiate & before body seen", Inst, Gen_Id);
-         Error_Msg_N ("\Program_Error will be raised at run time", Inst);
+         if Inst_Attrs.Elab_Warnings_OK then
+            Error_Msg_NE
+              ("??cannot instantiate & before body seen", Inst, Gen_Id);
+            Error_Msg_N ("\Program_Error will be raised at run time", Inst);
+         end if;
 
          --  Mark the instantiation as a guarantee ABE. This automatically
          --  suppresses the instantiation of the generic body.
diff --git a/gcc/ada/sem_prag.adb b/gcc/ada/sem_prag.adb
index 219ccf5..17ce6ac 100644
--- a/gcc/ada/sem_prag.adb
+++ b/gcc/ada/sem_prag.adb
@@ -15021,24 +15021,6 @@ package body Sem_Prag is
 
                Next (Arg);
             end loop Outer;
-
-            --  Give a warning if operating in static mode with one of the
-            --  gnatwl/-gnatwE (elaboration warnings enabled) switches set.
-
-            if Elab_Warnings
-              and not Dynamic_Elaboration_Checks
-
-              --  pragma Elaborate not allowed in SPARK mode anyway. We
-              --  already complained about it, no point in generating any
-              --  further complaint.
-
-              and SPARK_Mode /= On
-            then
-               Error_Msg_N
-                 ("?l?use of pragma Elaborate may not be safe", N);
-               Error_Msg_N
-                 ("?l?use pragma Elaborate_All instead if possible", N);
-            end if;
          end Elaborate;
 
          -------------------
diff --git a/gcc/ada/sem_res.adb b/gcc/ada/sem_res.adb
index 84f19a7..4348793 100644
--- a/gcc/ada/sem_res.adb
+++ b/gcc/ada/sem_res.adb
@@ -5830,9 +5830,10 @@ package body Sem_Res is
       --  resolution, and expansion are over.
 
       Mark_Elaboration_Attributes
-        (N_Id   => N,
-         Checks => True,
-         Modes  => True);
+        (N_Id     => N,
+         Checks   => True,
+         Modes    => True,
+         Warnings => True);
 
       --  The context imposes a unique interpretation with type Typ on a
       --  procedure or function call. Find the entity of the subprogram that
@@ -7833,6 +7834,9 @@ package body Sem_Res is
             Set_Is_Elaboration_Checks_OK_Node
               (Entry_Call, Is_Elaboration_Checks_OK_Node (N));
 
+            Set_Is_Elaboration_Warnings_OK_Node
+              (Entry_Call, Is_Elaboration_Warnings_OK_Node (N));
+
             Set_Is_SPARK_Mode_On_Node
               (Entry_Call, Is_SPARK_Mode_On_Node (N));
 
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 576a759..f582113 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -17827,10 +17827,11 @@ package body Sem_Util is
    ---------------------------------
 
    procedure Mark_Elaboration_Attributes
-     (N_Id   : Node_Or_Entity_Id;
-      Checks : Boolean := False;
-      Level  : Boolean := False;
-      Modes  : Boolean := False)
+     (N_Id     : Node_Or_Entity_Id;
+      Checks   : Boolean := False;
+      Level    : Boolean := False;
+      Modes    : Boolean := False;
+      Warnings : Boolean := False)
    is
       function Elaboration_Checks_OK
         (Target_Id  : Entity_Id;
@@ -18013,6 +18014,13 @@ package body Sem_Util is
                Set_Is_SPARK_Mode_On_Node (N);
             end if;
          end if;
+
+         --  Mark the status of elaboration warnings in effect. Do not reset
+         --  the status in case the node is reanalyzed with warnings off.
+
+         if Warnings and then not Is_Elaboration_Warnings_OK_Node (N) then
+            Set_Is_Elaboration_Warnings_OK_Node (N, Elab_Warnings);
+         end if;
       end Mark_Elaboration_Attributes_Node;
 
    --  Start of processing for Mark_Elaboration_Attributes
diff --git a/gcc/ada/sem_util.ads b/gcc/ada/sem_util.ads
index a12b260..c2d67f8 100644
--- a/gcc/ada/sem_util.ads
+++ b/gcc/ada/sem_util.ads
@@ -2087,16 +2087,19 @@ package Sem_Util is
    --  cleaned up during resolution.
 
    procedure Mark_Elaboration_Attributes
-     (N_Id   : Node_Or_Entity_Id;
-      Checks : Boolean := False;
-      Level  : Boolean := False;
-      Modes  : Boolean := False);
+     (N_Id     : Node_Or_Entity_Id;
+      Checks   : Boolean := False;
+      Level    : Boolean := False;
+      Modes    : Boolean := False;
+      Warnings : Boolean := False);
    --  Preserve relevant elaboration-related properties of the context in
-   --  arbitrary entity or node N_Id. When flag Checks is set, the routine
-   --  saves the status of Elaboration_Check. When flag Level is set, the
-   --  routine captures the declaration level of N_Id if applicable. When
-   --  flag Modes is set, the routine saves the Ghost and SPARK modes in
-   --  effect if applicable.
+   --  arbitrary entity or node N_Id. The flags control the properties as
+   --  follows:
+   --
+   --    Checks   - Save the status of Elaboration_Check
+   --    Level    - Save the declaration level of N_Id (if appicable)
+   --    Modes    - Save the Ghost and SPARK modes in effect (if applicable)
+   --    Warnings - Save the status of Elab_Warnings
 
    function Matching_Static_Array_Bounds
      (L_Typ : Node_Id;
diff --git a/gcc/ada/sinfo.adb b/gcc/ada/sinfo.adb
index 06f62c5..afb3ece 100644
--- a/gcc/ada/sinfo.adb
+++ b/gcc/ada/sinfo.adb
@@ -1886,7 +1886,7 @@ package body Sinfo is
    begin
       pragma Assert (False
         or else NT (N).Nkind = N_Call_Marker);
-      return Flag3 (N);
+      return Flag6 (N);
    end Is_Dispatching_Call;
 
    function Is_Dynamic_Coextension
@@ -1933,6 +1933,21 @@ package body Sinfo is
       return Flag9 (N);
    end Is_Elaboration_Code;
 
+   function Is_Elaboration_Warnings_OK_Node
+      (N : Node_Id) return Boolean is
+   begin
+      pragma Assert (False
+        or else NT (N).Nkind = N_Call_Marker
+        or else NT (N).Nkind = N_Entry_Call_Statement
+        or else NT (N).Nkind = N_Function_Call
+        or else NT (N).Nkind = N_Function_Instantiation
+        or else NT (N).Nkind = N_Package_Instantiation
+        or else NT (N).Nkind = N_Procedure_Call_Statement
+        or else NT (N).Nkind = N_Procedure_Instantiation
+        or else NT (N).Nkind = N_Requeue_Statement);
+      return Flag3 (N);
+   end Is_Elaboration_Warnings_OK_Node;
+
    function Is_Elsif
       (N : Node_Id) return Boolean is
    begin
@@ -5322,7 +5337,7 @@ package body Sinfo is
    begin
       pragma Assert (False
         or else NT (N).Nkind = N_Call_Marker);
-      Set_Flag3 (N, Val);
+      Set_Flag6 (N, Val);
    end Set_Is_Dispatching_Call;
 
    procedure Set_Is_Dynamic_Coextension
@@ -5369,6 +5384,21 @@ package body Sinfo is
       Set_Flag9 (N, Val);
    end Set_Is_Elaboration_Code;
 
+   procedure Set_Is_Elaboration_Warnings_OK_Node
+      (N : Node_Id; Val : Boolean := True) is
+   begin
+      pragma Assert (False
+        or else NT (N).Nkind = N_Call_Marker
+        or else NT (N).Nkind = N_Entry_Call_Statement
+        or else NT (N).Nkind = N_Function_Call
+        or else NT (N).Nkind = N_Function_Instantiation
+        or else NT (N).Nkind = N_Package_Instantiation
+        or else NT (N).Nkind = N_Procedure_Call_Statement
+        or else NT (N).Nkind = N_Procedure_Instantiation
+        or else NT (N).Nkind = N_Requeue_Statement);
+      Set_Flag3 (N, Val);
+   end Set_Is_Elaboration_Warnings_OK_Node;
+
    procedure Set_Is_Elsif
       (N : Node_Id; Val : Boolean := True) is
    begin
diff --git a/gcc/ada/sinfo.ads b/gcc/ada/sinfo.ads
index f14d2d1..278b456 100644
--- a/gcc/ada/sinfo.ads
+++ b/gcc/ada/sinfo.ads
@@ -1709,7 +1709,7 @@ package Sinfo is
    --    If this flag is set, the aspect or policy is not analyzed for semantic
    --    correctness, so any expressions etc will not be marked as analyzed.
 
-   --  Is_Dispatching_Call (Flag3-Sem)
+   --  Is_Dispatching_Call (Flag6-Sem)
    --    Present in call marker nodes. Set when the related call which prompted
    --    the creation of the marker is dispatching.
 
@@ -1724,12 +1724,23 @@ package Sinfo is
    --    a use clause is "used" in the current source.
 
    --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
-   --    Present in nodes which represent an elaboration scenario. Those are
-   --    assignment statement, attribute reference, call marker, entry call
-   --    statement, expanded name, function call, identifier, instantiation,
-   --    procedure call statement, and requeue statement nodes. Set when the
-   --    node appears within a context which allows for the generation of
-   --    run-time ABE checks. This flag detemines whether the ABE Processing
+   --    Present in the following nodes:
+   --
+   --      assignment statement
+   --      attribute reference
+   --      call marker
+   --      entry call statement
+   --      expanded name
+   --      function call
+   --      function instantiation
+   --      identifier
+   --      package instantiation
+   --      procedure call statement
+   --      procedure instantiation
+   --      requeue statement
+   --
+   --    Set when the node appears within a context which allows the generation
+   --    of run-time ABE checks. This flag detemines whether the ABE Processing
    --    phase generates conditional ABE checks and guaranteed ABE failures.
 
    --  Is_Elaboration_Code (Flag9-Sem)
@@ -1737,6 +1748,22 @@ package Sinfo is
    --    the elaboration flag of a package or subprogram when the corresponding
    --    body is successfully elaborated.
 
+   --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
+   --    Present in the following nodes:
+   --
+   --      call marker
+   --      entry call statement
+   --      function call
+   --      function instantiation
+   --      package instantiation
+   --      procedure call statement
+   --      procedure instantiation
+   --      requeue statement
+   --
+   --    Set when the node appears within a context where elaboration warnings
+   --    are enabled. This flag determines whether the ABE processing phase
+   --    generates diagnostics on various elaboration issues.
+
    --  Is_Entry_Barrier_Function (Flag8-Sem)
    --    This flag is set on N_Subprogram_Declaration and N_Subprogram_Body
    --    nodes which emulate the barrier function of a protected entry body.
@@ -5487,6 +5514,7 @@ package Sinfo is
       --  Controlling_Argument (Node1-Sem) (set to Empty if not dispatching)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Do_Tag_Check (Flag13-Sem)
       --  plus fields for expression
 
@@ -5517,6 +5545,7 @@ package Sinfo is
       --  Controlling_Argument (Node1-Sem) (set to Empty if not dispatching)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Is_Expanded_Build_In_Place_Call (Flag11-Sem)
       --  Do_Tag_Check (Flag13-Sem)
       --  No_Side_Effect_Removal (Flag17-Sem)
@@ -6230,6 +6259,7 @@ package Sinfo is
       --  First_Named_Actual (Node4-Sem)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
 
       ------------------------------
       -- 9.5.4  Requeue Statement --
@@ -6247,6 +6277,7 @@ package Sinfo is
       --  Abort_Present (Flag15)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
 
       --------------------------
       -- 9.6  Delay Statement --
@@ -7044,6 +7075,7 @@ package Sinfo is
       --  Instance_Spec (Node5-Sem)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Is_Declaration_Level_Node (Flag5-Sem)
       --  Is_Known_Guaranteed_ABE (Flag18-Sem)
 
@@ -7057,6 +7089,7 @@ package Sinfo is
       --  Instance_Spec (Node5-Sem)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Is_Declaration_Level_Node (Flag5-Sem)
       --  Must_Override (Flag14) set if overriding indicator present
       --  Must_Not_Override (Flag15) set if not_overriding indicator present
@@ -7072,6 +7105,7 @@ package Sinfo is
       --  Instance_Spec (Node5-Sem)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Is_Declaration_Level_Node (Flag5-Sem)
       --  Must_Override (Flag14) set if overriding indicator present
       --  Must_Not_Override (Flag15) set if not_overriding indicator present
@@ -7827,9 +7861,10 @@ package Sinfo is
       --  Target (Node1-Sem)
       --  Is_Elaboration_Checks_OK_Node (Flag1-Sem)
       --  Is_SPARK_Mode_On_Node (Flag2-Sem)
-      --  Is_Dispatching_Call (Flag3-Sem)
+      --  Is_Elaboration_Warnings_OK_Node (Flag3-Sem)
       --  Is_Source_Call (Flag4-Sem)
       --  Is_Declaration_Level_Node (Flag5-Sem)
+      --  Is_Dispatching_Call (Flag6-Sem)
       --  Is_Known_Guaranteed_ABE (Flag18-Sem)
 
       ------------------------
@@ -9699,7 +9734,7 @@ package Sinfo is
      (N : Node_Id) return Boolean;    -- Flag15
 
    function Is_Dispatching_Call
-     (N : Node_Id) return Boolean;    -- Flag3
+     (N : Node_Id) return Boolean;    -- Flag6
 
    function Is_Dynamic_Coextension
      (N : Node_Id) return Boolean;    -- Flag18
@@ -9713,6 +9748,9 @@ package Sinfo is
    function Is_Elaboration_Code
      (N : Node_Id) return Boolean;    -- Flag9
 
+   function Is_Elaboration_Warnings_OK_Node
+     (N : Node_Id) return Boolean;    -- Flag3
+
    function Is_Elsif
      (N : Node_Id) return Boolean;    -- Flag13
 
@@ -10794,7 +10832,7 @@ package Sinfo is
      (N : Node_Id; Val : Boolean := True);    -- Flag15
 
    procedure Set_Is_Dispatching_Call
-     (N : Node_Id; Val : Boolean := True);    -- Flag3
+     (N : Node_Id; Val : Boolean := True);    -- Flag6
 
    procedure Set_Is_Dynamic_Coextension
      (N : Node_Id; Val : Boolean := True);    -- Flag18
@@ -10808,6 +10846,9 @@ package Sinfo is
    procedure Set_Is_Elaboration_Code
      (N : Node_Id; Val : Boolean := True);    -- Flag9
 
+   procedure Set_Is_Elaboration_Warnings_OK_Node
+     (N : Node_Id; Val : Boolean := True);    -- Flag3
+
    procedure Set_Is_Elsif
      (N : Node_Id; Val : Boolean := True);    -- Flag13
 
@@ -13340,6 +13381,7 @@ package Sinfo is
    pragma Inline (Is_Effective_Use_Clause);
    pragma Inline (Is_Elaboration_Checks_OK_Node);
    pragma Inline (Is_Elaboration_Code);
+   pragma Inline (Is_Elaboration_Warnings_OK_Node);
    pragma Inline (Is_Elsif);
    pragma Inline (Is_Entry_Barrier_Function);
    pragma Inline (Is_Expanded_Build_In_Place_Call);
@@ -13700,6 +13742,7 @@ package Sinfo is
    pragma Inline (Set_Is_Effective_Use_Clause);
    pragma Inline (Set_Is_Elaboration_Checks_OK_Node);
    pragma Inline (Set_Is_Elaboration_Code);
+   pragma Inline (Set_Is_Elaboration_Warnings_OK_Node);
    pragma Inline (Set_Is_Elsif);
    pragma Inline (Set_Is_Entry_Barrier_Function);
    pragma Inline (Set_Is_Expanded_Build_In_Place_Call);