ada: Do not generate warning about missing overriding indicator

We were previously generating a warning about a missing overriding
indicator in some cases when a dispatching subprogram is declared.
In at least some (and perhaps all) cases where this warning was generated,
it was incorrect. It was also generated very infrequently. The simple
solution is to stop generating the warning.

gcc/ada/ChangeLog:

	* sem_disp.adb
	(Check_Dispatching_Operation): Delete code to generate
	"missing overriding indicator" warning. Update comments.

diff --git a/gcc/ada/sem_disp.adb b/gcc/ada/sem_disp.adb
index 4881d6f2f8b3d31c7028371e2694d0ee305325e5..d13367659ac264b82385842410e56792100963e9 100644 (file)
--- a/gcc/ada/sem_disp.adb
+++ b/gcc/ada/sem_disp.adb
@@ -80,7 +80,7 @@ package body Sem_Disp is
    --  parameter); otherwise returns empty.
 
    function Find_Hidden_Overridden_Primitive (S : Entity_Id) return Entity_Id;
-   --  [Ada 2012:AI-0125] Find an inherited hidden primitive of the dispatching
+   --  [AI05-0125] Find an inherited hidden primitive of the dispatching
    --  type of S that has the same name of S, a type-conformant profile, an
    --  original corresponding operation O that is a primitive of a visible
    --  ancestor of the dispatching type of S and O is visible at the point of
@@ -91,7 +91,8 @@ package body Sem_Disp is
    --  This routine does not search for non-hidden primitives since they are
    --  covered by the normal Ada 2005 rules. Its name was motivated by an
    --  intermediate version of AI05-0125 where this term was proposed to
-   --  name these entities in the RM.
+   --  name these entities in the RM. FWIW, note that AI05-0125 was
+   --  not approved; it was voted "No Action".
 
    function Is_Inherited_Public_Operation (Op : Entity_Id) return Boolean;
    --  Check whether a primitive operation is inherited from an operation
@@ -1710,9 +1711,8 @@ package body Sem_Disp is
 
       Ovr_Subp := Old_Subp;
 
-      --  [Ada 2012:AI-0125]: Search for inherited hidden primitive that may be
-      --  overridden by Subp. This only applies to source subprograms, and
-      --  their declaration must carry an explicit overriding indicator.
+      --  Search for inherited hidden primitive that may be
+      --  overridden by Subp. This only applies to source subprograms.
 
       if No (Ovr_Subp)
         and then Ada_Version >= Ada_2012
@@ -1721,16 +1721,6 @@ package body Sem_Disp is
           Nkind (Unit_Declaration_Node (Subp)) = N_Subprogram_Declaration
       then
          Ovr_Subp := Find_Hidden_Overridden_Primitive (Subp);
-
-         --  Warn if the proper overriding indicator has not been supplied.
-
-         if Present (Ovr_Subp)
-           and then
-             not Must_Override (Specification (Unit_Declaration_Node (Subp)))
-           and then not In_Instance
-         then
-            Error_Msg_NE ("missing overriding indicator for&??", Subp, Subp);
-         end if;
       end if;
 
       --  Now it should be a correct primitive operation, put it in the list