Ada: Fix spurious warning for renaming of component of VFA record

This is a regression present on the mainline and all active branches: the
compiler gives a spurious "is not referenced" warning for the renaming of
a component of a Volatile_Full_Access record.

gcc/ada/
	PR ada/107536
	* exp_ch2.adb (Expand_Renaming): Mark the entity as referenced.

gcc/testsuite/
	* gnat.dg/renaming18.adb: New test.

2 files changed, 31 insertions, 1 deletions

diff --git a/gcc/ada/exp_ch2.adb b/gcc/ada/exp_ch2.adb
index 06a276bbc03..6c276bac3c1 100644
--- a/gcc/ada/exp_ch2.adb
+++ b/gcc/ada/exp_ch2.adb
@@ -704,9 +704,15 @@ package body Exp_Ch2 is
       T : constant Entity_Id := Etype (N);
 
    begin
+      --  Mark the entity as referenced since this reference is going away
+
+      Set_Referenced (E);
+
+      --  Now rewrite the reference as a copy of the renamed object
+
       Rewrite (N, New_Copy_Tree (Renamed_Object (E)));
 
-      --  We mark the copy as unanalyzed, so that it is sure to be reanalyzed
+      --  Mark the copy as unanalyzed to make sure that it is reanalyzed
       --  at the top level. This is needed in the packed case since we
       --  specifically avoided expanding packed array references when the
       --  renaming declaration was analyzed.
diff --git a/gcc/testsuite/gnat.dg/renaming18.adb b/gcc/testsuite/gnat.dg/renaming18.adb
new file mode 100644
index 00000000000..a4da04d3d62
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/renaming18.adb
@@ -0,0 +1,24 @@
+-- { dg-do compile }
+-- { dg-options "-gnatwu" }
+
+procedure Renaming18 is
+
+  type T is record
+    Item : Integer;
+  end record;
+
+  A_T : T;
+  Item : Integer renames A_T.Item;
+
+  type VFA_T is record
+    Item : Integer;
+  end record
+  with Volatile_Full_Access;
+
+  A_VFA_T : VFA_T;
+  VFA_Item : Integer renames A_VFA_T.Item; -- { dg-bogus "is not referenced" }
+
+begin
+  Item := 42;
+  VFA_Item := 42;
+end;