diff --git a/src/boot.c b/src/boot.c
index ace6f88..eb54c76 100644
--- a/src/boot.c
+++ b/src/boot.c
@@ -57,8 +57,9 @@ static struct {
     { 0xff, "5.25\" 320k floppy 2s/40tr/8sec" },
 };
 
-#if defined __alpha || defined __ia64__ || defined __s390x__ || defined __x86_64__ \
- || defined __ppc64__ || defined __bfin__ || defined __MICROBLAZE__
+#if defined __alpha || defined __arm || defined __ia64__ || defined __s390x__ \
+ || defined __x86_64__ || defined __ppc64__ || defined __bfin__ \
+ || defined __MICROBLAZE__
 /* Unaligned fields must first be copied byte-wise */
 #define GET_UNALIGNED_W(f)			\
     ({						\