diff --git a/include/osmocom/gsm/tlv.h b/include/osmocom/gsm/tlv.h
index 8caddae..4a9bd27 100644
--- a/include/osmocom/gsm/tlv.h
+++ b/include/osmocom/gsm/tlv.h
@@ -68,9 +68,9 @@
 	uint16_t ret;
 
 	if (len <= TVLV_MAX_ONEBYTE)
-		return TLV_GROSS_LEN(len);
+		ret = TLV_GROSS_LEN(len);
 	else
-		return TL16V_GROSS_LEN(len);
+		ret = TL16V_GROSS_LEN(len);
 
 	if (tag > TVLV_MAX_ONEBYTE)
 		ret += 1;