2017-10-09 Bob Duff <duff@adacore.com>

	* exp_ch6.adb (Make_Build_In_Place_Call_In_Object_Declaration): Use
	Defining_Identifier (Obj_Decl) in two places, because it might have
	changed.
	* exp_ch6.adb (Make_Build_In_Place_Call_In_Allocator): Deal with cases
	involving 'Input on (not visibly) derived types.

2017-10-09  Hristian Kirtchev  <kirtchev@adacore.com>

	* atree.adb: Add new soft link Rewriting_Proc.
	(Rewrite): Invoke the subprogram attached to the rewriting soft link.
	(Set_Rewriting_Proc): New routine.
	* attree.ads: Add new access-to-subprogram type Rewrite_Proc.
	(Set_Rewriting_Proc): New routine.
	* checks.adb (Install_Primitive_Elaboration_Check): Use 'E' character
	for *E*laboration flag to maintain consistency with other elaboration
	flag generating subprograms.
	* debug.adb: Document the new usage of flag -gnatdL.
	* einfo.adb: Node19 is now used as Receiving_Entry.  Node39 is now used
	as Protected_Subprogram.  Flag148 is now used as
	Is_Elaboration_Checks_OK_Id.  Flag302 is now used as
	Is_Initial_Condition_Procedure.
	(Is_Elaboration_Checks_OK_Id): New routine.
	(Is_Initial_Condition_Procedure): New routine.
	(Protected_Subprogram): New routine.
	(Receiving_Entry): New routine.
	(SPARK_Pragma): Update assertion.
	(SPARK_Pragma_Inherited): Update assertion.
	(Suppress_Elaboration_Warnings): Removed.
	(Set_Is_Elaboration_Checks_OK_Id): New routine.
	(Set_Is_Initial_Condition_Procedure): New routine.
	(Set_Protected_Subprogram): New routine.
	(Set_Receiving_Entry): New routine.
	(Set_SPARK_Pragma): Update assertion.
	(Set_SPARK_Pragma_Inherited): Update assertion.
	(Write_Entity_Flags): Update the output for Flag148 and Flag302.
	(Write_Field19_Name): Add output for Receiving_Entry.
	(Write_Field39_Name): Add output for Protected_Subprogram.
	(Write_Field40_Name): Update the output for SPARK_Pragma.
	* einfo.ads: New attributes Is_Elaboration_Checks_OK_Id,
	Is_Initial_Condition_Procedure, Protected_Subprogram, Receiving_Entry.
	Remove attribute Suppress_Elaboration_Warnings.  Update the stricture
	of various entities.
	(Is_Elaboration_Checks_OK_Id): New routine along with pragma Inline.
	(Is_Initial_Condition_Procedure): New routine along with pragma Inline.
	(Protected_Subprogram): New routine along with pragma Inline.
	(Receiving_Entry): New routine along with pragma Inline.
	(Suppress_Elaboration_Warnings): Removed.
	(Set_Is_Elaboration_Checks_OK_Id): New routine along with pragma
	Inline.
	(Set_Is_Initial_Condition_Procedure): New routine along with pragma
	Inline.
	(Set_Protected_Subprogram): New routine along with pragma Inline.
	(Set_Receiving_Entry): New routine along with pragma Inline.
	(Set_Suppress_Elaboration_Warnings): Removed.
	* exp_ch3.adb (Build_Init_Procedure): Use name _Finalizer to maintain
	consistency with other finalizer generating subprograms.
	(Default_Initialize_Object): Mark the block which wraps the call to
	finalize as being part of initialization.
	* exp_ch7.adb (Expand_N_Package_Declaration): Directly expand pragma
	Initial_Condition.
	(Expand_N_Package_Body): Directly expand pragma Initial_Condition.
	(Next_Suitable_Statement): Update the comment on usage. Skip over call
	markers generated by the ABE mechanism.
	* exp_ch9.adb (Activation_Call_Loc): New routine.
	(Add_Accept): Link the accept procedure to the original entry.
	(Build_Protected_Sub_Specification): Link the protected or unprotected
	version to the original subprogram.
	(Build_Task_Activation_Call): Code cleanup. Use a source location which
	is very close to the "begin" or "end" keywords when generating the
	activation call.
	* exp_prag.adb (Expand_Pragma_Initial_Condition): Reimplemented.
	* exp_spark.adb (Expand_SPARK): Use Expand_SPARK_N_Loop_Statement to
	process loops.
	(Expand_SPARK_N_Loop_Statement): New routine.
	(Expand_SPARK_N_Object_Declaration): Code cleanup. Partially insert the
	call to the Default_Initial_Condition procedure.
	(Expand_SPARK_Op_Ne): Renamed to Expand_SPARK_N_Op_Ne.
	* exp_util.adb (Build_DIC_Procedure_Body): Capture the SPARK_Mode in
	effect.
	(Build_DIC_Procedure_Declaration): Capture the SPARK_Mode in effect.
	(Insert_Actions): Add processing for N_Call_Marker.
	(Kill_Dead_Code): Explicitly kill an elaboration scenario.
	* exp_util.ads (Make_Invariant_Call): Update the comment on usage.
	* frontend.adb: Initialize Sem_Elab. Process all saved top level
	elaboration scenarios for ABE issues.
	* gcc-interface/trans.c (gnat_to_gnu): Add processing for N_Call_Marker
	nodes.
	* lib.adb (Earlier_In_Extended_Unit): New variant.
	* sem.adb (Analyze): Ignore N_Call_Marker nodes.
	(Preanalysis_Active): New routine.
	* sem.ads (Preanalysis_Active): New routine.
	* sem_attr.adb (Analyze_Access_Attribute): Save certain
	elaboration-related attributes. Save the scenario for ABE processing.
	* sem_ch3.adb (Analyze_Object_Declaration): Save the SPARK mode in
	effect. Save certain elaboration-related attributes.
	* sem_ch5.adb (Analyze_Assignment): Save certain elaboration-related
	attributes. Save the scenario for ABE processing.
	* sem_ch6.adb (Analyze_Abstract_Subprogram_Declaration): Save the SPARK
	mode in effect. Save certain elaboration-related attributes.
	(Analyze_Subprogram_Body_Helper): Skip N_Call_Marker nodes when
	locating the first real statement.
	(Analyze_Subprogram_Declaration): Save the SPARK mode in effect. Save
	certain elaboration-related attributes.
	* sem_ch7.adb (Analyze_Package_Declaration): Do not suppress
	elaboration warnings.
	* sem_ch8.adb (Attribute_Renaming): Mark a subprogram body which was
	generated for purposes of wrapping an attribute used as a generic
	actual.
	(Find_Direct_Name): Save certain elaboration-related attributes. Save
	the scenario for ABE processing.
	(Find_Expanded_Name): Save certain elaboration-related attributes. Save
	the scenario for ABE processing.
	* sem_ch9.adb (Analyze_Entry_Declaration): Save certain
	elaboration-related attributes.
	(Analyze_Requeue): Save certain elaboration-related attributes. Save
	the scenario for ABE processing.
	(Analyze_Single_Task_Declaration): Save certain elaboration-related
	attributes.
	(Analyze_Task_Type_Declaration): Save certain elaboration-related
	attributes.
	* sem_ch12.adb (Analyze_Generic_Package_Declaration): Save certain
	elaboration-related attributes.
	(Analyze_Generic_Subprogram_Declaration): Save the SPARK mode in
	effect. Save certain elaboration-related attributes.
	(Analyze_Package_Instantiation): Save certain elaboration-related
	attributes.  Save the scenario for ABE processing. Create completing
	bodies in case the instantiation results in a guaranteed ABE.
	(Analyze_Subprogram_Instantiation): Save certain elaboration-related
	attributes Save the scenario for ABE processing. Create a completing
	body in case the instantiation results in a guaranteed ABE.
	(Provide_Completing_Bodies): New routine.
	* sem_elab.ads: Brand new implementation.
	* sem_prag.adb (Analyze_Pragma, cases Elaborate, Elaborate_All,
	Elaborate_Body): Do not suppress elaboration warnings.
	* sem_res.adb (Make_Call_Into_Operator): Set the parent field of the
	operator.
	(Resolve_Call): Save certain elaboration-related attributes. Save the
	scenario for ABE processing.
	(Resolve_Entity_Name): Do not perform any ABE processing here.
	(Resolve_Entry_Call): Inherit certain attributes from the original call.
	* sem_util.adb (Begin_Keyword_Location): New routine.
	(Defining_Entity): Update the parameter profile. Add processing for
	concurrent subunits that are rewritten as null statements.
	(End_Keyword_Location): New routine.
	(Find_Enclosing_Scope): New routine.
	(In_Instance_Visible_Part): Code cleanup.
	(In_Subtree): Update the parameter profile. Add new version.
	(Is_Preelaborable_Aggregate): New routine.
	(Is_Preelaborable_Construct): New routine.
	(Mark_Elaboration_Attributes): New routine.
	(Scope_Within): Update the parameter profile.
	(Scope_Within_Or_Same): Update the parameter profile.
	* sem_util.ads (Begin_Keyword_Location): New routine.
	(Defining_Entity): Update the parameter profile and the comment on
	usage.
	(End_Keyword_Location): New routine.
	(Find_Enclosing_Scope): New routine.
	(In_Instance_Visible_Part): Update the parameter profile.
	(In_Subtree): Update the parameter profile. Add new version.
	(Is_Preelaborable_Aggregate): New routine.
	(Is_Preelaborable_Construct): New routine.
	(Mark_Elaboration_Attributes): New routine.
	(Scope_Within): Update the parameter profile and the comment on usage.
	(Scope_Within_Or_Same): Update the parameter profile and the comment on
	usage.
	* sem_warn.adb (Check_Infinite_Loop_Warning): Use Has_Condition_Actions
	to determine whether a loop has meaningful condition actions.
	(Has_Condition_Actions): New routine.
	* sinfo.adb (ABE_Is_Certain): Removed.
	(Is_Declaration_Level_Node): New routine.
	(Is_Dispatching_Call): New routine.
	(Is_Elaboration_Checks_OK_Node): New routine.
	(Is_Initialization_Block): New routine.
	(Is_Known_Guaranteed_ABE): New routine.
	(Is_Recorded_Scenario): New routine.
	(Is_Source_Call): New routine.
	(Is_SPARK_Mode_On_Node): New routine.
	(No_Elaboration_Check): Removed.
	(Target): New routine.
	(Was_Attribute_Reference): New routine.
	(Set_ABE_Is_Certain): Removed.
	(Set_Is_Declaration_Level_Node): New routine.
	(Set_Is_Dispatching_Call): New routine.
	(Set_Is_Elaboration_Checks_OK_Node): New routine.
	(Set_Is_Initialization_Block): New routine.
	(Set_Is_Known_Guaranteed_ABE): New routine.
	(Set_Is_Recorded_Scenario): New routine.
	(Set_Is_Source_Call): New routine.
	(Set_Is_SPARK_Mode_On_Node): New routine.
	(Set_No_Elaboration_Check): Removed.
	(Set_Target): New routine.
	(Set_Was_Attribute_Reference): New routine.
	* sinfo.ads: Remove attribute ABE_Is_Certain.  Attribute
	Do_Discriminant_Check now utilizes Flag3.  Attribute
	No_Side_Effect_Removal now utilizes Flag17.  Add new node
	N_Call_Marker.  Update the structure of various nodes.
	(ABE_Is_Certain): Removed along with pragma Inline.
	(Is_Declaration_Level_Node): New routine along with pragma Inline.
	(Is_Dispatching_Call): New routine along with pragma Inline.
	(Is_Elaboration_Checks_OK_Node): New routine along with pragma Inline.
	(Is_Initialization_Block): New routine along with pragma Inline.
	(Is_Known_Guaranteed_ABE): New routine along with pragma Inline.
	(Is_Recorded_Scenario): New routine along with pragma Inline.
	(Is_Source_Call): New routine along with pragma Inline.
	(Is_SPARK_Mode_On_Node): New routine along with pragma Inline.
	(No_Elaboration_Check): Removed along with pragma Inline.
	(Target): New routine along with pragma Inline.
	(Was_Attribute_Reference): New routine along with pragma Inline.
	(Set_ABE_Is_Certain): Removed along with pragma Inline.
	(Set_Is_Declaration_Level_Node): New routine along with pragma Inline.
	(Set_Is_Dispatching_Call): New routine along with pragma Inline.
	(Set_Is_Elaboration_Checks_OK_Node): New routine along with pragma
	Inline.
	(Set_Is_Initialization_Block): New routine along with pragma Inline.
	(Set_Is_Known_Guaranteed_ABE): New routine along with pragma Inline.
	(Set_Is_Recorded_Scenario): New routine along with pragma Inline.
	(Set_Is_Source_Call): New routine along with pragma Inline.
	(Set_Is_SPARK_Mode_On_Node): New routine along with pragma Inline.
	(Set_No_Elaboration_Check): Removed along with pragma Inline.
	(Set_Target): New routine along with pragma Inline.
	(Set_Was_Attribute_Reference): New routine along with pragma Inline.
	* sprint.adb (Sprint_Node_Actual): Add an entry for N_Call_Marker.




git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@253559 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 88 insertions, 39 deletions

diff --git a/gcc/ada/sem_util.ads b/gcc/ada/sem_util.ads
index 30c35cb1591..2ebd54f3989 100644
--- a/gcc/ada/sem_util.ads
+++ b/gcc/ada/sem_util.ads
@@ -202,6 +202,10 @@ package Sem_Util is
    --  given, and the reference N is not in the same extended source unit as
    --  the declaration of T.
 
+   function Begin_Keyword_Location (N : Node_Id) return Source_Ptr;
+   --  Given block statement, entry body, package body, subprogram body, or
+   --  task body N, return the closest source location to the "begin" keyword.
+
    function Build_Actual_Subtype
      (T : Entity_Id;
       N : Node_Or_Entity_Id) return Node_Id;
@@ -547,8 +551,9 @@ package Sem_Util is
    --  instead of 0).
 
    function Defining_Entity
-     (N               : Node_Id;
-      Empty_On_Errors : Boolean := False) return Entity_Id;
+     (N                  : Node_Id;
+      Empty_On_Errors    : Boolean := False;
+      Concurrent_Subunit : Boolean := False) return Entity_Id;
    --  Given a declaration N, returns the associated defining entity. If the
    --  declaration has a specification, the entity is obtained from the
    --  specification. If the declaration has a defining unit name, then the
@@ -572,6 +577,9 @@ package Sem_Util is
    --
    --  The former semantics is appropriate for the back end; the latter
    --  semantics is appropriate for the front end.
+   --
+   --  Set flag Concurrent_Subunit to handle rewritings of concurrent bodies
+   --  which act as subunits. Such bodies are generally rewritten as null.
 
    function Denotes_Discriminant
      (N                : Node_Id;
@@ -685,6 +693,12 @@ package Sem_Util is
    --  Utility function to return the Ada entity of the subprogram enclosing
    --  the entity E, if any. Returns Empty if no enclosing subprogram.
 
+   function End_Keyword_Location (N : Node_Id) return Source_Ptr;
+   --  Given block statement, entry body, package body, package declaration,
+   --  protected body, [single] protected type declaration, subprogram body,
+   --  task body, or [single] task type declaration N, return the closest
+   --  source location of the "end" keyword.
+
    procedure Ensure_Freeze_Node (E : Entity_Id);
    --  Make sure a freeze node is allocated for entity E. If necessary, build
    --  and initialize a new freeze node and set Has_Delayed_Freeze True for E.
@@ -740,12 +754,6 @@ package Sem_Util is
    --  Call is set to the node for the corresponding call. If the node N is not
    --  an actual parameter then Formal and Call are set to Empty.
 
-   function Find_Specific_Type (CW : Entity_Id) return Entity_Id;
-   --  Find specific type of a class-wide type, and handle the case of an
-   --  incomplete type coming either from a limited_with clause or from an
-   --  incomplete type declaration. If resulting type is private return its
-   --  full view.
-
    function Find_Body_Discriminal
      (Spec_Discriminant : Entity_Id) return Entity_Id;
    --  Given a discriminant of the record type that implements a task or
@@ -762,9 +770,12 @@ package Sem_Util is
    --  discriminant at the same position in this new type.
 
    function Find_Enclosing_Iterator_Loop (Id : Entity_Id) return Entity_Id;
-   --  Given an arbitrary entity, try to find the nearest enclosing iterator
-   --  loop. If such a loop is found, return the entity of its identifier (the
-   --  E_Loop scope), otherwise return Empty.
+   --  Find the nearest iterator loop which encloses arbitrary entity Id. If
+   --  such a loop exists, return the entity of its identifier (E_Loop scope),
+   --  otherwise return Empty.
+
+   function Find_Enclosing_Scope (N : Node_Id) return Entity_Id;
+   --  Find the nearest scope which encloses arbitrary node N
 
    function Find_Loop_In_Conditional_Block (N : Node_Id) return Node_Id;
    --  Find the nested loop statement in a conditional block. Loops subject to
@@ -868,6 +879,12 @@ package Sem_Util is
    --  If the state space is that of a package, Pack_Id denotes its entity,
    --  otherwise Pack_Id is Empty.
 
+   function Find_Specific_Type (CW : Entity_Id) return Entity_Id;
+   --  Find specific type of a class-wide type, and handle the case of an
+   --  incomplete type coming either from a limited_with clause or from an
+   --  incomplete type declaration. If resulting type is private return its
+   --  full view.
+
    function Find_Static_Alternative (N : Node_Id) return Node_Id;
    --  N is a case statement whose expression is a compile-time value.
    --  Determine the alternative chosen, so that the code of non-selected
@@ -1134,8 +1151,7 @@ package Sem_Util is
    --  subprogram or entry and returns it, or if no subprogram can be found,
    --  returns Empty.
 
-   function Get_Task_Body_Procedure (E : Entity_Id) return Node_Id;
-   pragma Inline (Get_Task_Body_Procedure);
+   function Get_Task_Body_Procedure (E : Entity_Id) return Entity_Id;
    --  Given an entity for a task type or subtype, retrieves the
    --  Task_Body_Procedure field from the corresponding task type declaration.
 
@@ -1259,14 +1275,14 @@ package Sem_Util is
    --  as expressed in pragma Refined_State. This function does not take into
    --  account the visible refinement region of abstract state Id.
 
-   function Has_Null_Body (Proc_Id : Entity_Id) return Boolean;
-   --  Determine whether the body of procedure Proc_Id contains a sole
-   --  null statement, possibly followed by an optional return. Used to
-   --  optimize useless calls to assertion checks.
+   function Has_Non_Trivial_Precondition (Subp : Entity_Id) return Boolean;
+   --  Determine whether subprogram Subp has a class-wide precondition that is
+   --  not statically True.
 
-      function Has_Non_Trivial_Precondition (P : Entity_Id) return Boolean;
-      --  True if subprogram has a class-wide precondition that is not
-      --  statically True.
+   function Has_Null_Body (Proc_Id : Entity_Id) return Boolean;
+   --  Determine whether the body of procedure Proc_Id contains a sole null
+   --  statement, possibly followed by an optional return. Used to optimize
+   --  useless calls to assertion checks.
 
    function Has_Null_Exclusion (N : Node_Id) return Boolean;
    --  Determine whether node N has a null exclusion
@@ -1357,9 +1373,10 @@ package Sem_Util is
    --  Returns True if current scope is with the private part or the body of
    --  an instance. Other semantic checks are suppressed in this context.
 
-   function In_Instance_Visible_Part return Boolean;
-   --  Returns True if current scope is within the visible part of a package
-   --  instance, where several additional semantic checks apply.
+   function In_Instance_Visible_Part
+     (Id : Entity_Id := Current_Scope) return Boolean;
+   --  Returns True if arbitrary entity Id is within the visible part of a
+   --  package instance, where several additional semantic checks apply.
 
    function In_Package_Body return Boolean;
    --  Returns True if current scope is within a package body
@@ -1382,9 +1399,17 @@ package Sem_Util is
    --  appearing anywhere within such a construct (that is it does not need
    --  to be directly within).
 
-   function In_Subtree (Root : Node_Id; N : Node_Id) return Boolean;
+   function In_Subtree (N : Node_Id; Root : Node_Id) return Boolean;
    --  Determine whether node N is within the subtree rooted at Root
 
+   function In_Subtree
+     (N     : Node_Id;
+      Root1 : Node_Id;
+      Root2 : Node_Id) return Boolean;
+   --  Determine whether node N is within the subtree rooted at Root1 or Root2.
+   --  This version is more efficient than calling the single root version of
+   --  Is_Subtree twice.
+
    function In_Visible_Part (Scope_Id : Entity_Id) return Boolean;
    --  Determine whether a declaration occurs within the visible part of a
    --  package specification. The package must be on the scope stack, and the
@@ -1765,6 +1790,14 @@ package Sem_Util is
    --  persistent. A private type is potentially persistent if the full type
    --  is potentially persistent.
 
+   function Is_Preelaborable_Aggregate (Aggr : Node_Id) return Boolean;
+   --  Determine whether aggregate Aggr violates the restrictions of
+   --  preelaborable constructs as defined in ARM 10.2.1(5-9).
+
+   function Is_Preelaborable_Construct (N : Node_Id) return Boolean;
+   --  Determine whether arbitrary node N violates the restrictions of
+   --  preelaborable constructs as defined in ARM 10.2.1(5-9).
+
    function Is_Protected_Self_Reference (N : Node_Id) return Boolean;
    --  Return True if node N denotes a protected type name which represents
    --  the current instance of a protected object according to RM 9.4(21/2).
@@ -2028,6 +2061,24 @@ package Sem_Util is
    --  statement in Statements (HSS) that has Comes_From_Source set. If no
    --  such statement exists, Empty is returned.
 
+   procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id);
+   --  Given a node which designates the context of analysis and an origin in
+   --  the tree, traverse from Root_Nod and mark all allocators as either
+   --  dynamic or static depending on Context_Nod. Any incorrect marking is
+   --  cleaned up during resolution.
+
+   procedure Mark_Elaboration_Attributes
+     (N_Id   : Node_Or_Entity_Id;
+      Checks : Boolean := False;
+      Level  : Boolean := False;
+      Modes  : 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.
+
    function Matching_Static_Array_Bounds
      (L_Typ : Node_Id;
       R_Typ : Node_Id) return Boolean;
@@ -2035,12 +2086,6 @@ package Sem_Util is
    --  same number of dimensions, and the same static bounds for each index
    --  position.
 
-   procedure Mark_Coextensions (Context_Nod : Node_Id; Root_Nod : Node_Id);
-   --  Given a node which designates the context of analysis and an origin in
-   --  the tree, traverse from Root_Nod and mark all allocators as either
-   --  dynamic or static depending on Context_Nod. Any incorrect marking is
-   --  cleaned up during resolution.
-
    function May_Be_Lvalue (N : Node_Id) return Boolean;
    --  Determines if N could be an lvalue (e.g. an assignment left hand side).
    --  An lvalue is defined as any expression which appears in a context where
@@ -2460,15 +2505,19 @@ package Sem_Util is
    --  this is the case, and False if no scalar parts are present (meaning that
    --  the result of Valid_Scalars applied to T is always vacuously True).
 
-   function Scope_Within_Or_Same (Scope1, Scope2 : Entity_Id) return Boolean;
-   --  Determines if the entity Scope1 is the same as Scope2, or if it is
-   --  inside it, where both entities represent scopes. Note that scopes
-   --  are only partially ordered, so Scope_Within_Or_Same (A,B) and
-   --  Scope_Within_Or_Same (B,A) can both be False for a given pair A,B.
-
-   function Scope_Within (Scope1, Scope2 : Entity_Id) return Boolean;
-   --  Like Scope_Within_Or_Same, except that this function returns
-   --  False in the case where Scope1 and Scope2 are the same scope.
+   function Scope_Within
+     (Inner : Entity_Id;
+      Outer : Entity_Id) return Boolean;
+   --  Determine whether scope Inner appears within scope Outer. Note that
+   --  scopes are partially ordered, so Scope_Within (A, B) and Scope_Within
+   --  (B, A) may both return False.
+
+   function Scope_Within_Or_Same
+     (Inner : Entity_Id;
+      Outer : Entity_Id) return Boolean;
+   --  Determine whether scope Inner appears within scope Outer or both renote
+   --  the same scope. Note that scopes are partially ordered, so Scope_Within
+   --  (A, B) and Scope_Within (B, A) may both return False.
 
    procedure Set_Convention (E : Entity_Id; Val : Convention_Id);
    --  Same as Basic_Set_Convention, but with an extra check for access types.