[gcc(refs/users/guojiufu/heads/personal-branch)] [Ada] Avoid "others => <>" association in resolved record aggregates

[Jiu Fu Guo]

https://gcc.gnu.org/g:0c25b7838090b7ff130b74b22b00ab09d59a5dd2

commit 0c25b7838090b7ff130b74b22b00ab09d59a5dd2
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Tue Mar 17 16:58:24 2020 +0100

    [Ada] Avoid "others => <>" association in resolved record aggregates
    
    2020-06-11  Piotr Trojanek  <trojanek@adacore.com>
    
    gcc/ada/
    
            * sem_aggr.adb (Add_Association): Add assertion about the formal
            parameters.
            (Propagate_Discriminants): Always add an explicit component
            association, so that an "others => <>" association is never
            needed.

Diff:
---
 gcc/ada/sem_aggr.adb | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/gcc/ada/sem_aggr.adb b/gcc/ada/sem_aggr.adb
index b80810dffad..a0f878442f4 100644
--- a/gcc/ada/sem_aggr.adb
+++ b/gcc/ada/sem_aggr.adb
@@ -3393,6 +3393,8 @@ package body Sem_Aggr is
          --  If this is a box association the expression is missing, so use the
          --  Sloc of the aggregate itself for the new association.
 
+         pragma Assert (Present (Expr) xor Is_Box_Present);
+
          if Present (Expr) then
             Loc := Sloc (Expr);
          else
@@ -3804,8 +3806,6 @@ package body Sem_Aggr is
       is
          Loc : constant Source_Ptr := Sloc (N);
 
-         Needs_Box : Boolean := False;
-
          procedure Process_Component (Comp : Entity_Id);
          --  Add one component with a box association to the inner aggregate,
          --  and recurse if component is itself composite.
@@ -3834,7 +3834,9 @@ package body Sem_Aggr is
                Build_Constrained_Itype
                  (New_Aggr, T, Component_Associations (New_Aggr));
             else
-               Needs_Box := True;
+               Add_Association
+                 (Comp, Empty, Component_Associations (Aggr),
+                  Is_Box_Present => True);
             end if;
          end Process_Component;
 
@@ -3885,14 +3887,6 @@ package body Sem_Aggr is
                Next_Component (Comp);
             end loop;
          end if;
-
-         if Needs_Box then
-            Append_To (Component_Associations (Aggr),
-              Make_Component_Association (Loc,
-                Choices     => New_List (Make_Others_Choice (Loc)),
-                Expression  => Empty,
-                Box_Present => True));
-         end if;
       end Propagate_Discriminants;
 
       -----------------------