--- a/usr/iscsi/iscsid.c
+++ b/usr/iscsi/iscsid.c
@@ -1074,7 +1074,7 @@ void iscsi_rsp_set_residual(struct iscsi_cmd_rsp *rsp, struct scsi_cmd *scmd)
 struct iscsi_sense_data {
 	uint16_t length;
 	uint8_t  data[0];
-} __packed;
+} __attribute__((__packed__));
 
 static int iscsi_cmd_rsp_build(struct iscsi_task *task)
 {
--- a/usr/iscsi/iser.c
+++ b/usr/iscsi/iser.c
@@ -92,7 +92,7 @@ char *iser_portal_addr;
 struct iscsi_sense_data {
 	uint16_t length;
 	uint8_t data[0];
-} __packed;
+} __attribute__((__packed__));
 
 static size_t buf_pool_sz_mb = DEFAULT_POOL_SIZE_MB;
 static int cq_vector = -1;