diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 7bf0cc11fb..8c1fd30b71 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2012-04-25  Tom Tromey  <tromey@redhat.com>
+
+	* gdb.threads/linux-dp.exp: Unset 'seen' before 'array set'.
+
 2012-04-18  Siddhesh Poyarekar  <siddhesh@redhat.com>
 	    Jan Kratochvil  <jan.kratochvil@redhat.com>
 
diff --git a/gdb/testsuite/gdb.threads/linux-dp.exp b/gdb/testsuite/gdb.threads/linux-dp.exp
index d7fa1259d5..d74cded8ce 100644
--- a/gdb/testsuite/gdb.threads/linux-dp.exp
+++ b/gdb/testsuite/gdb.threads/linux-dp.exp
@@ -339,8 +339,8 @@ proc check_philosopher_stack {thread seen_name} {
 }
 
 set any_interesting 0
+catch {unset seen}
 array set seen {}
-unset seen
 for {set i 1} {$i <= $nthreads} {incr i} {
     if [check_philosopher_stack $i seen] {
 	set any_interesting 1