diff --git a/src/core/tcp.c b/src/core/tcp.c
index 3fc5b296..f1ed03a3 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -312,14 +312,7 @@ tcp_listen(struct tcp_pcb *pcb)
 #if LWIP_CALLBACK_API
   lpcb->accept = tcp_accept_null;
 #endif /* LWIP_CALLBACK_API */
-/* workaround for compile error: assignment requires modifiable lvalue in TCP_REG */ 
-#if LWIP_TCP_REG_COMPILE_ERROR
-  /* place this pcb at the start the "listening pcbs" list */
-  lpcb->next = tcp_listen_pcbs;
-  tcp_listen_pcbs = lpcb;
-#else
-  TCP_REG((struct tcp_pcb **)&tcp_listen_pcbs, (struct tcp_pcb *)lpcb);
-#endif
+  TCP_REG(&tcp_listen_pcbs, lpcb);
   return (struct tcp_pcb *)lpcb;
 }
 /*-----------------------------------------------------------------------------------*/
diff --git a/src/include/lwip/tcp.h b/src/include/lwip/tcp.h
index 821406c5..7b7aa17c 100644
--- a/src/include/lwip/tcp.h
+++ b/src/include/lwip/tcp.h
@@ -417,6 +417,7 @@ extern struct tcp_pcb *tcp_tmp_pcb;      /* Only used for temporary storage. */
 				tcp_tmp_pcb = tcp_tmp_pcb->next) { \
                                 ASSERT("TCP_REG: already registered\n", tcp_tmp_pcb != npcb); \
                             } \
+							/* TODO: state field doesn't exist in listen pcbs */ \
                             ASSERT("TCP_REG: pcb->state != CLOSED", npcb->state != CLOSED); \
                             npcb->next = *pcbs; \
                             ASSERT("TCP_REG: npcb->next != npcb", npcb->next != npcb); \