diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index fd8318b73f1..60fbf113820 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,10 @@
+2006-09-13  Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR ada/28591
+	* decl.c (components_to_record): Defer emitting debug info for the
+	record type associated with the variant until after we are sure to
+	actually use it.
+
 2006-09-13  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR ada/21952
diff --git a/gcc/ada/decl.c b/gcc/ada/decl.c
index 6a8f23424c5..6d70a159f3d 100644
--- a/gcc/ada/decl.c
+++ b/gcc/ada/decl.c
@@ -5659,10 +5659,12 @@ components_to_record (tree gnu_record_type, Node_Id component_list,
 		= TYPE_SIZE_UNIT (gnu_record_type);
 	    }
 
+	  /* Create the record for the variant.  Note that we defer emitting
+	     debug info for it until after we are sure to actually use it.  */
 	  components_to_record (gnu_variant_type, Component_List (variant),
 				NULL_TREE, packed, definition,
 				&gnu_our_rep_list, !all_rep_and_size, all_rep,
-				false, unchecked_union);
+				true, unchecked_union);
 
 	  gnu_qual = choices_to_gnu (gnu_discriminant,
 				     Discrete_Choices (variant));
@@ -5676,6 +5678,13 @@ components_to_record (tree gnu_record_type, Node_Id component_list,
 	    gnu_field = TYPE_FIELDS (gnu_variant_type);
 	  else
 	    {
+	      /* Emit debug info for the record.  We used to throw away
+		 empty records but we no longer do that because we need
+		 them to generate complete debug info for the variant;
+		 otherwise, the union type definition will be lacking
+		 the fields associated with these empty variants.  */
+	      write_record_type_debug_info (gnu_variant_type);
+
 	      gnu_field = create_field_decl (gnu_inner_name, gnu_variant_type,
 					     gnu_union_type, 0,
 					     (all_rep_and_size
@@ -5695,12 +5704,6 @@ components_to_record (tree gnu_record_type, Node_Id component_list,
 	  gnu_variant_list = gnu_field;
 	}
 
-      /* We used to delete the empty variants from the end. However,
-         we no longer do that because we need them to generate complete
-         debugging information for the variant record.  Otherwise,
-         the union type definition will be missing the fields associated
-         to these empty variants.  */
-
       /* Only make the QUAL_UNION_TYPE if there are any non-empty variants.  */
       if (gnu_variant_list)
 	{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f9de5f24209..ae45deee404 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2006-09-13  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/specs/unchecked_union.ads: New test.
+
 2006-09-13  Richard Sandiford  <richard@codesourcery.com>
 
 	PR rtl-optimization/28982
diff --git a/gcc/testsuite/gnat.dg/specs/unchecked_union.ads b/gcc/testsuite/gnat.dg/specs/unchecked_union.ads
new file mode 100644
index 00000000000..260f781d89d
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/specs/unchecked_union.ads
@@ -0,0 +1,20 @@
+-- PR ada/28591
+-- Reported by Martin Michlmayr <tbm@cyrius.com>
+
+-- { dg-do compile }
+-- { dg-options "-g" }
+
+with Interfaces; use Interfaces;
+
+package Unchecked_Union is
+   type Mode_Type is (Mode_B2);
+
+   type Value_Union (Mode : Mode_Type := Mode_B2) is record
+      case Mode is
+         when Mode_B2 =>
+            B2 : Integer_32;
+      end case;
+   end record;
+   pragma Unchecked_Union (Value_Union);
+
+end Unchecked_Union;