diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b09ca01a88a..01aa9dc59c1 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2007-02-05  Alexandre Oliva  <aoliva@redhat.com>
+
+	PR debug/30189
+	* dwarf2out.c (modified_type_die): Follow DECL_ORIGINAL_TYPE
+	even if cv-qualification is the same.
+
 2007-02-05  Geoffrey Keating  <geoffk@apple.com>
 
 	* config/rs6000/darwin-tramp.asm (__trampoline_setup): Call
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 186c979abb5..d529d8c879d 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -8519,9 +8519,11 @@ modified_type_die (tree type, int is_const_type, int is_volatile_type,
 	  gen_type_die (qualified_type, context_die);
 	  return lookup_type_die (qualified_type);
 	}
-      else if (DECL_ORIGINAL_TYPE (name)
-	       && (is_const_type < TYPE_READONLY (dtype)
-		   || is_volatile_type < TYPE_VOLATILE (dtype)))
+      else if (is_const_type < TYPE_READONLY (dtype)
+	       || is_volatile_type < TYPE_VOLATILE (dtype)
+	       || (is_const_type <= TYPE_READONLY (dtype)
+		   && is_volatile_type <= TYPE_VOLATILE (dtype)
+		   && DECL_ORIGINAL_TYPE (name) != type))
 	/* cv-unqualified version of named type.  Just use the unnamed
 	   type to which it refers.  */
 	return modified_type_die (DECL_ORIGINAL_TYPE (name),
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9723b16106f..abfefcc631f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2007-02-05  Alexandre Oliva  <aoliva@redhat.com>
+
+	PR debug/30189
+	* gcc.dg/pr30189.c: New test.
+
 2007-02-05      Dwarakanath Rajagopal <dwarak.rajagopal@amd.com>
 
         * gcc.dg/i386-cpuid.h: Test whether SSE4A is supported
diff --git a/gcc/testsuite/gcc.dg/pr30189.c b/gcc/testsuite/gcc.dg/pr30189.c
new file mode 100644
index 00000000000..6aa963e7a10
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr30189.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-g -O" } */
+
+extern void foo (void);
+
+static
+void baz (int i)
+{
+  foo ();
+  typedef char A[i];
+  struct { A b; } *x = 0;
+}
+
+void
+bar (i)
+{
+  baz (i);
+}