diff --git a/src/core/pbuf.c b/src/core/pbuf.c
index 6047738..af63e60 100644
--- a/src/core/pbuf.c
+++ b/src/core/pbuf.c
@@ -1119,7 +1119,8 @@
 struct pbuf*
 pbuf_skip(struct pbuf* in, u16_t in_offset, u16_t* out_offset)
 {
-  return LWIP_CONST_CAST(struct pbuf*, pbuf_skip_const(in, in_offset, out_offset));
+  const struct pbuf* out = pbuf_skip_const(in, in_offset, out_offset);
+  return LWIP_CONST_CAST(struct pbuf*, out);
 }
 
 /**