-- which is the current instance type can only be applied when the type
-- is limited.
+ procedure Check_Suspicious_Modulus (Utype : Entity_Id);
+ -- Give warning for modulus of 8, 16, 32, or 64 given as an explicit
+ -- integer literal without an explicit corresponding size clause. The
+ -- caller has checked that Utype is a modular integer type.
+
function After_Last_Declaration return Boolean;
-- If Loc is a freeze_entity that appears after the last declaration
-- in the scope, inhibit error messages on late completion.
end if;
end Check_Current_Instance;
+ ------------------------------
+ -- Check_Suspicious_Modulus --
+ ------------------------------
+
+ procedure Check_Suspicious_Modulus (Utype : Entity_Id) is
+ Decl : constant Node_Id := Declaration_Node (Underlying_Type (Utype));
+
+ begin
+ if Nkind (Decl) = N_Full_Type_Declaration then
+ declare
+ Tdef : constant Node_Id := Type_Definition (Decl);
+ begin
+ if Nkind (Tdef) = N_Modular_Type_Definition then
+ declare
+ Modulus : constant Node_Id :=
+ Original_Node (Expression (Tdef));
+ begin
+ if Nkind (Modulus) = N_Integer_Literal then
+ declare
+ Modv : constant Uint := Intval (Modulus);
+ Sizv : constant Uint := RM_Size (Utype);
+
+ begin
+ -- First case, modulus and size are the same. This
+ -- happens if you have something like mod 32, with
+ -- an explicit size of 32, this is for sure a case
+ -- where the warning is given, since it is seems
+ -- very unlikely that someone would want e.g. a
+ -- five bit type stored in 32 bits. It is much
+ -- more likely they wanted a 32-bit type.
+
+ if Modv = Sizv then
+ null;
+
+ -- Second case, the modulus is 32 or 64 and no
+ -- size clause is present. This is a less clear
+ -- case for giving the warning, but in the case
+ -- of 32/64 (5-bit or 6-bit types) these seem rare
+ -- enough that it is a likely error (and in any
+ -- case using 2**5 or 2**6 in these cases seems
+ -- clearer. We don't include 8 or 16 here, simply
+ -- because in practice 3-bit and 4-bit types are
+ -- more common and too many false positives if
+ -- we warn in these cases.
+
+ elsif not Has_Size_Clause (Utype)
+ and then (Modv = Uint_32 or else Modv = Uint_64)
+ then
+ null;
+
+ -- No warning needed
+
+ else
+ return;
+ end if;
+
+ -- If we fall through, give warning
+
+ Error_Msg_Uint_1 := Modv;
+ Error_Msg_N
+ ("?2 '*'*^' may have been intended here",
+ Modulus);
+ end;
+ end if;
+ end;
+ end if;
+ end;
+ end if;
+ end Check_Suspicious_Modulus;
+
------------------------
-- Freeze_Record_Type --
------------------------
elsif Is_Integer_Type (E) then
Adjust_Esize_For_Alignment (E);
+ if Is_Modular_Integer_Type (E) then
+ Check_Suspicious_Modulus (E);
+ end if;
+
elsif Is_Access_Type (E) then
-- Check restriction for standard storage pool