diff --git a/libitm/ChangeLog b/libitm/ChangeLog
index 8efaef5f3297..ad07098d3268 100644
--- a/libitm/ChangeLog
+++ b/libitm/ChangeLog
@@ -1,3 +1,9 @@
+2012-01-14  Torvald Riegel  <triegel@redhat.com>
+
+	* local.cc (GTM::gtm_undolog::rollback): Truncate undo log after
+	rolling back.
+	* containers.h (GTM::vector::set_size): New.
+
 2012-01-14  Torvald Riegel  <triegel@redhat.com>
 
 	PR libitm/51855
diff --git a/libitm/containers.h b/libitm/containers.h
index 394b6f2508ec..36905659da29 100644
--- a/libitm/containers.h
+++ b/libitm/containers.h
@@ -92,6 +92,7 @@ class vector
   size_t size() const { return m_size; }
   size_t capacity() const { return this->capacity; }
 
+  void set_size (size_t size) { m_size = size; }
   void clear() { m_size = 0; }
 
   iterator push() {
diff --git a/libitm/local.cc b/libitm/local.cc
index 5645a12bab89..d0d96cea625a 100644
--- a/libitm/local.cc
+++ b/libitm/local.cc
@@ -61,6 +61,7 @@ gtm_undolog::rollback (gtm_thread* tx, size_t until_size)
           if (likely(ptr > top || (uint8_t*)ptr + len <= bot))
             __builtin_memcpy (ptr, &undolog[i], len);
 	}
+      undolog.set_size(until_size);
     }
 }