[COMMITTED] ada: Follow-up improvement to implementation of storage models

["Marc Poulhiès" <poulhies@adacore.com>]

From: Eric Botcazou <ebotcazou@adacore.com>

It avoids to recreate an actual subtype for an explicit dereference.

gcc/ada/

	* sem_util.adb (Get_Actual_Subtype): For an explicit dereference,
	return the Actual_Designated_Subtype if it is present.
	(Get_Actual_Subtype_If_Available): Likewise.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/sem_util.adb | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 8bce0229867..ad74de6b6f6 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -10017,6 +10017,14 @@ package body Sem_Util is
       then
          return Actual_Subtype (Entity (N));
 
+      --  Similarly, if we have an explicit dereference, then we get the
+      --  actual subtype from the node itself if one has been built.
+
+      elsif Nkind (N) = N_Explicit_Dereference
+        and then Present (Actual_Designated_Subtype (N))
+      then
+         return Actual_Designated_Subtype (N);
+
       --  Actual subtype of unchecked union is always itself. We never need
       --  the "real" actual subtype. If we did, we couldn't get it anyway
       --  because the discriminant is not available. The restrictions on
@@ -10130,6 +10138,14 @@ package body Sem_Util is
       then
          return Actual_Subtype (Entity (N));
 
+      --  Similarly, if we have an explicit dereference, then we get the
+      --  actual subtype from the node itself if one has been built.
+
+      elsif Nkind (N) = N_Explicit_Dereference
+        and then Present (Actual_Designated_Subtype (N))
+      then
+         return Actual_Designated_Subtype (N);
+
       --  Otherwise the Etype of N is returned unchanged
 
       else
-- 
2.40.0