diff --git a/features/storage/filesystem/fat/FATFileSystem.cpp b/features/storage/filesystem/fat/FATFileSystem.cpp
index 81d142c8b0..90229131f2 100644
--- a/features/storage/filesystem/fat/FATFileSystem.cpp
+++ b/features/storage/filesystem/fat/FATFileSystem.cpp
@@ -280,9 +280,8 @@ extern "C" DRESULT disk_ioctl(BYTE pdrv, BYTE cmd, void *buff)
 
 // Filesystem implementation (See FATFilySystem.h)
 FATFileSystem::FATFileSystem(const char *name, BlockDevice *bd)
-    : FileSystem(name), _id(-1)
+    : FileSystem(name), _fs(), _id(-1)
 {
-    _fs = { 0 };
     if (bd) {
         mount(bd);
     }