[gcc r13-3780] ada: Reject limited objects in array and record delta aggregates

[Marc Poulhi?s <dkm@gcc.gnu.org>]

https://gcc.gnu.org/g:79e02673e97d1a359ca1fc2dc3f6d51d0debe7d8

commit r13-3780-g79e02673e97d1a359ca1fc2dc3f6d51d0debe7d8
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Thu Oct 14 23:31:21 2021 +0200

    ada: Reject limited objects in array and record delta aggregates
    
    For array delta aggregates the base expression cannot be limited; for
    record delta aggregates the base expression can only be limited if it is
    a newly constructed object.
    
    gcc/ada/
    
            * sem_aggr.adb (Resolve_Delta_Aggregate): Implement rules related
            to limited objects appearing as the base expression.

Diff:
---
 gcc/ada/sem_aggr.adb | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/gcc/ada/sem_aggr.adb b/gcc/ada/sem_aggr.adb
index 383f18f7301..4da05dd7317 100644
--- a/gcc/ada/sem_aggr.adb
+++ b/gcc/ada/sem_aggr.adb
@@ -3421,6 +3421,18 @@ package body Sem_Aggr is
       Analyze_And_Resolve (Base, Typ);
 
       if Is_Array_Type (Typ) then
+         --  For an array_delta_aggregate, the base_expression and each
+         --  expression in every array_component_association shall be of a
+         --  nonlimited type; RM 4.3.4(13/5). However, to prevent repeated
+         --  errors we only check the base expression and not array component
+         --  associations.
+
+         if Is_Limited_Type (Etype (Base)) then
+            Error_Msg_N
+              ("array delta aggregate shall be of a nonlimited type", Base);
+            Explain_Limited_Type (Etype (Base), Base);
+         end if;
+
          Resolve_Delta_Array_Aggregate (N, Typ);
       else
 
@@ -3432,6 +3444,11 @@ package body Sem_Aggr is
               ("delta aggregates for record types must use (), not '[']", N);
          end if;
 
+         --  The base_expression of a record_delta_aggregate can be of a
+         --  limited type only if it is newly constructed; RM 7.5(2.1/5).
+
+         Check_Expr_OK_In_Limited_Aggregate (Base);
+
          Resolve_Delta_Record_Aggregate (N, Typ);
       end if;