diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index fa4ab8834e..da246a0587 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2010-05-21  Pierre Muller  <muller@ics.u-strasbg.fr>
+
+	* windows-nat.c (display_selector): Call GetLastError to give better
+	failure explanation.
+
 2010-05-24  Pedro Alves  <pedro@codesourcery.com>
 
 	* config.in: Regenerate.
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 5966b882b6..0ec393f889 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1032,7 +1032,11 @@ display_selector (HANDLE thread, DWORD sel)
     }
   else
     {
-      printf_filtered ("Invalid selector 0x%lx.\n",sel);
+      DWORD err = GetLastError ();
+      if (err == ERROR_NOT_SUPPORTED)
+	printf_filtered ("Function not supported\n");
+      else
+	printf_filtered ("Invalid selector 0x%lx.\n",sel);
       return 0;
     }
 }