diff --git a/openbsc/src/gprs/gprs_gsup_messages.c b/openbsc/src/gprs/gprs_gsup_messages.c
index 8996fe2..9d9b6be 100644
--- a/openbsc/src/gprs/gprs_gsup_messages.c
+++ b/openbsc/src/gprs/gprs_gsup_messages.c
@@ -153,7 +153,7 @@
 
 parse_error:
 	LOGP(DGPRS, LOGL_ERROR,
-	     "GSUP IE type %d, length %d invalid in PDP info\n", iei, value_len);
+	     "GSUP IE type %d, length %zu invalid in PDP info\n", iei, value_len);
 
 	return -1;
 }