* [COMMITTED] ada: Fix detection of components with per-object constraints
@ 2024-05-07 8:00 Marc Poulhiès
0 siblings, 0 replies; only message in thread
From: Marc Poulhiès @ 2024-05-07 8:00 UTC (permalink / raw)
To: gcc-patches; +Cc: Piotr Trojanek
From: Piotr Trojanek <trojanek@adacore.com>
Routine Contains_POC (where POC means "per-object constraint") was
failing to detect expressions of the form "Current_Type'Access", because
it was comparing prefix (typically an N_Identifier) with a scope
(typically an N_Definining_Entity). This was harmless, because these
expressions are detected anyway in Analyze_Access_Attribute, together
with uses of 'Unconstrained_Access and 'Unchecked_Access.
Also, this routine was failing to detect the use of discriminants in
array types with constrained subtype indication, e.g.:
type T (D : Integer) is record
C : array (Integer range 1 .. D);
end record;
It is simpler to just reuse Has_Discriminant_Dependent_Constraint and
leave detection of access attributes to Analyze_Access_Attribute.
gcc/ada/
* sem_attr.adb (Analyze_Access_Attribute): Prevent search from
going too far.
* sem_ch3.adb (Analyze_Component_Declaration): Remove
Contains_POC; reuse Has_Discriminant_Dependent_Constraint.
Tested on x86_64-pc-linux-gnu, committed on master.
---
gcc/ada/sem_attr.adb | 20 +++++++-----
gcc/ada/sem_ch3.adb | 74 ++------------------------------------------
2 files changed, 14 insertions(+), 80 deletions(-)
diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
index c067d882048..c17f67356ef 100644
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -1014,16 +1014,20 @@ package body Sem_Attr is
Q : Node_Id := Parent (N);
begin
- while Present (Q)
- and then Nkind (Q) /= N_Component_Declaration
- loop
+ while Present (Q) loop
+ if Nkind (Q) = N_Component_Declaration then
+ Set_Has_Per_Object_Constraint
+ (Defining_Identifier (Q), True);
+ exit;
+
+ -- Prevent the search from going too far
+
+ elsif Is_Body_Or_Package_Declaration (Q) then
+ exit;
+ end if;
+
Q := Parent (Q);
end loop;
-
- if Present (Q) then
- Set_Has_Per_Object_Constraint
- (Defining_Identifier (Q), True);
- end if;
end;
if Nkind (P) = N_Expanded_Name then
diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb
index 737ea809492..ad9e9317b15 100644
--- a/gcc/ada/sem_ch3.adb
+++ b/gcc/ada/sem_ch3.adb
@@ -1960,71 +1960,11 @@ package body Sem_Ch3 is
T : Entity_Id;
P : Entity_Id;
- function Contains_POC (Constr : Node_Id) return Boolean;
- -- Determines whether a constraint uses the discriminant of a record
- -- type thus becoming a per-object constraint (POC).
-
function Is_Known_Limited (Typ : Entity_Id) return Boolean;
-- Typ is the type of the current component, check whether this type is
-- a limited type. Used to validate declaration against that of
-- enclosing record.
- ------------------
- -- Contains_POC --
- ------------------
-
- function Contains_POC (Constr : Node_Id) return Boolean is
- begin
- -- Prevent cascaded errors
-
- if Error_Posted (Constr) then
- return False;
- end if;
-
- case Nkind (Constr) is
- when N_Attribute_Reference =>
- return Attribute_Name (Constr) = Name_Access
- and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
-
- when N_Discriminant_Association =>
- return Denotes_Discriminant (Expression (Constr));
-
- when N_Identifier =>
- return Denotes_Discriminant (Constr);
-
- when N_Index_Or_Discriminant_Constraint =>
- declare
- IDC : Node_Id;
-
- begin
- IDC := First (Constraints (Constr));
- while Present (IDC) loop
-
- -- One per-object constraint is sufficient
-
- if Contains_POC (IDC) then
- return True;
- end if;
-
- Next (IDC);
- end loop;
-
- return False;
- end;
-
- when N_Range =>
- return Denotes_Discriminant (Low_Bound (Constr))
- or else
- Denotes_Discriminant (High_Bound (Constr));
-
- when N_Range_Constraint =>
- return Denotes_Discriminant (Range_Expression (Constr));
-
- when others =>
- return False;
- end case;
- end Contains_POC;
-
----------------------
-- Is_Known_Limited --
----------------------
@@ -2208,18 +2148,8 @@ package body Sem_Ch3 is
-- The component declaration may have a per-object constraint, set
-- the appropriate flag in the defining identifier of the subtype.
- if Present (Subtype_Indication (Component_Definition (N))) then
- declare
- Sindic : constant Node_Id :=
- Subtype_Indication (Component_Definition (N));
- begin
- if Nkind (Sindic) = N_Subtype_Indication
- and then Present (Constraint (Sindic))
- and then Contains_POC (Constraint (Sindic))
- then
- Set_Has_Per_Object_Constraint (Id);
- end if;
- end;
+ if Has_Discriminant_Dependent_Constraint (Id) then
+ Set_Has_Per_Object_Constraint (Id);
end if;
-- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
--
2.43.2
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2024-05-07 8:00 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-05-07 8:00 [COMMITTED] ada: Fix detection of components with per-object constraints Marc Poulhiès
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).