diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 393c378..defdd74 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -589,7 +589,9 @@ static dir_entry *get_dentfromdir(fsdata *mydata, int startsect,
 				  char *filename, dir_entry *retdent,
 				  int dols)
 {
+#ifdef CONFIG_SUPPORT_VFAT
 	__u16 prevcksum = 0xffff;
+#endif
 	__u32 curclust = START(retdent);
 	int files = 0, dirs = 0;
 
@@ -828,7 +830,9 @@ do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 	fsdata datablock;
 	fsdata *mydata = &datablock;
 	dir_entry *dentptr = NULL;
+#ifdef CONFIG_SUPPORT_VFAT
 	__u16 prevcksum = 0xffff;
+#endif
 	char *subname = "";
 	__u32 cursect;
 	int idx, isdir = 0;
@@ -944,7 +948,9 @@ do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 
 		for (i = 0; i < DIRENTSPERBLOCK; i++) {
 			char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+#ifdef CONFIG_SUPPORT_VFAT
 			__u8 csum;
+#endif
 
 			l_name[0] = '\0';
 			if (dentptr->name[0] == DELETED_FLAG) {
@@ -952,7 +958,9 @@ do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 				continue;
 			}
 
+#ifdef CONFIG_SUPPORT_VFAT
 			csum = mkcksum(dentptr->name, dentptr->ext);
+#endif
 			if (dentptr->attr & ATTR_VOLUME) {
 #ifdef CONFIG_SUPPORT_VFAT
 				if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&