diff --git a/components/dfs/filesystems/elmfat/dfs_elm.c b/components/dfs/filesystems/elmfat/dfs_elm.c
index d8c38e96ae..80e99a5e94 100644
--- a/components/dfs/filesystems/elmfat/dfs_elm.c
+++ b/components/dfs/filesystems/elmfat/dfs_elm.c
@@ -945,7 +945,7 @@ DWORD get_fattime(void)
 {
     DWORD fat_time = 0;
 
-#ifdef RT_USING_LIBC
+#ifdef RT_USING_RTC
     time_t now;
     struct tm *p_tm;
     struct tm tm_now;