diff --git a/CHANGELOG b/CHANGELOG
index 72f467ab..45ed3bfd 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -49,6 +49,9 @@ HISTORY
 
  ++ Bugfixes:
 
+  2011-10-28: Simon Goldschmidt
+  * tcp_in.c: fixed bug #34638: Dead code in tcp_receive - pcb->dupacks
+
   2011-10-23: Simon Goldschmidt
   * mem.c: fixed bug #34429: possible memory corruption with
     LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT set to 1
diff --git a/src/core/tcp_in.c b/src/core/tcp_in.c
index 5d56bdbd..fa5a861f 100644
--- a/src/core/tcp_in.c
+++ b/src/core/tcp_in.c
@@ -918,8 +918,9 @@ tcp_receive(struct tcp_pcb *pcb)
             /* Clause 5 */
             if (pcb->lastack == ackno) {
               found_dupack = 1;
-              if (pcb->dupacks + 1 > pcb->dupacks)
+              if ((u8_t)(pcb->dupacks + 1) > pcb->dupacks) {
                 ++pcb->dupacks;
+              }
               if (pcb->dupacks > 3) {
                 /* Inflate the congestion window, but not if it means that
                    the value overflows. */