diff --git a/include/osmocore/msgb.h b/include/osmocore/msgb.h
index 5a88ac6..9b58e33 100644
--- a/include/osmocore/msgb.h
+++ b/include/osmocore/msgb.h
@@ -109,7 +109,7 @@
 static inline unsigned char *msgb_put(struct msgb *msgb, unsigned int len)
 {
 	unsigned char *tmp = msgb->tail;
-	if (msgb_tailroom(msgb) < len)
+	if (msgb_tailroom(msgb) < (int) len)
 		MSGB_ABORT(msgb, "Not enough tailroom msgb_push (%u < %u)\n",
 			   msgb_tailroom(msgb), len);
 	msgb->tail += len;
@@ -159,7 +159,7 @@
 }
 static inline unsigned char *msgb_push(struct msgb *msgb, unsigned int len)
 {
-	if (msgb_headroom(msgb) < len)
+	if (msgb_headroom(msgb) < (int) len)
 		MSGB_ABORT(msgb, "Not enough headroom msgb_push (%u < %u)\n",
 			   msgb_headroom(msgb), len);
 	msgb->data -= len;