diff --git a/src/core/tcp.c b/src/core/tcp.c
index 91f1c641..4f26df42 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -91,7 +91,7 @@ struct tcp_pcb *tcp_tw_pcbs;
 #define NUM_TCP_PCB_LISTS               4
 #define NUM_TCP_PCB_LISTS_NO_TIME_WAIT  3
 /** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
-struct tcp_pcb **tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
+struct tcp_pcb ** const tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
   &tcp_active_pcbs, &tcp_tw_pcbs};
 
 /** Only used for temporary storage. */