When detecting overlapping actuals we were only examining the type of
the first formal parameter, so that errors and warnings were depending
on the order of parameters.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* sem_warn.adb (Warn_On_Overlapping_Actuals): Examine types of
both formal parameters; refactor a complex detection of
by-reference types.diff --git a/gcc/ada/sem_warn.adb b/gcc/ada/sem_warn.adb
--- a/gcc/ada/sem_warn.adb
+++ b/gcc/ada/sem_warn.adb
@@ -3669,6 +3669,9 @@ package body Sem_Warn is
---------------------------------
procedure Warn_On_Overlapping_Actuals (Subp : Entity_Id; N : Node_Id) is
+ function Explicitly_By_Reference (Formal_Id : Entity_Id) return Boolean;
+ -- Returns True iff the type of Formal_Id is explicitly by-reference
+
function Refer_Same_Object
(Act1 : Node_Id;
Act2 : Node_Id) return Boolean;
@@ -3680,6 +3683,24 @@ package body Sem_Warn is
-- object_name is known to refer to the same object as the other name
-- (RM 6.4.1(6.11/3))
+ -----------------------------
+ -- Explicitly_By_Reference --
+ -----------------------------
+
+ function Explicitly_By_Reference
+ (Formal_Id : Entity_Id)
+ return Boolean
+ is
+ Typ : constant Entity_Id := Underlying_Type (Etype (Formal_Id));
+ begin
+ if Present (Typ) then
+ return Is_By_Reference_Type (Typ)
+ or else Convention (Typ) = Convention_Ada_Pass_By_Reference;
+ else
+ return False;
+ end if;
+ end Explicitly_By_Reference;
+
-----------------------
-- Refer_Same_Object --
-----------------------
@@ -3792,17 +3813,13 @@ package body Sem_Warn is
then
null;
- -- If type is explicitly not by-copy, assume that
- -- aliasing is intended.
+ -- If type is explicitly by-reference, then it is not
+ -- covered by the legality rule, which only applies to
+ -- elementary types. Actually, the aliasing is most
+ -- likely intended, so don't emit a warning either.
- elsif
- Present (Underlying_Type (Etype (Form1)))
- and then
- (Is_By_Reference_Type
- (Underlying_Type (Etype (Form1)))
- or else
- Convention (Underlying_Type (Etype (Form1))) =
- Convention_Ada_Pass_By_Reference)
+ elsif Explicitly_By_Reference (Form1)
+ or else Explicitly_By_Reference (Form2)
then
null;
@@ -3810,7 +3827,9 @@ package body Sem_Warn is
-- arrays and record types if switch is set.
elsif Ada_Version >= Ada_2012
- and then not Is_Elementary_Type (Etype (Form1))
+ and then not (Is_Elementary_Type (Etype (Form1))
+ and then
+ Is_Elementary_Type (Etype (Form2)))
and then not Warn_On_Overlap
then
null;
