diff --git a/utils/src/format.h b/utils/src/format.h
index 6251c8f8..6c37816d 100644
--- a/utils/src/format.h
+++ b/utils/src/format.h
@@ -212,8 +212,8 @@ struct scoutfs_segment_item {
 	__u8 nr_links;
 	__le32 skip_links[0];
 	/*
-	 * u8 key_bytes[key_len]
-	 * u8 val_bytes[val_len]
+	 * __u8 key_bytes[key_len]
+	 * __u8 val_bytes[val_len]
 	 */
 } __packed;
 
diff --git a/utils/src/ioctl.h b/utils/src/ioctl.h
index b8e8aa40..c1e7f6f9 100644
--- a/utils/src/ioctl.h
+++ b/utils/src/ioctl.h
@@ -114,7 +114,7 @@ struct scoutfs_ioctl_ino_path {
 } __packed;
 
 #define SCOUTFS_IOC_INO_PATH_CURSOR_BYTES \
-	(sizeof(u64) + SCOUTFS_NAME_LEN + 1)
+	(sizeof(__u64) + SCOUTFS_NAME_LEN + 1)
 
 /* Get a single path from the root to the given inode number */
 #define SCOUTFS_IOC_INO_PATH _IOW(SCOUTFS_IOCTL_MAGIC, 2, \