diff --git a/src/boot/filo.c b/src/boot/filo.c
index 157bec2057..cd14fa13b3 100644
--- a/src/boot/filo.c
+++ b/src/boot/filo.c
@@ -18,7 +18,7 @@
 #define autoboot(mem)
 #endif
 
-#ifndef AUTOBOOT_DELAY
+#if !AUTOBOOT_DELAY
 #define autoboot_delay() 0 /* success */
 #endif
 
diff --git a/src/stream/fs/ext2fs.c b/src/stream/fs/ext2fs.c
index f29fd8aeb1..9cf0bc6500 100644
--- a/src/stream/fs/ext2fs.c
+++ b/src/stream/fs/ext2fs.c
@@ -239,7 +239,7 @@ struct ext2_dir_entry
  * ffz = Find First Zero in word. Undefined if no zero exists,
  * so code should check against ~0UL first..
  */
-#if ARCH == 'i386'
+#ifdef __i386
 static __inline__ unsigned long
 ffz (unsigned long word)
 {
diff --git a/src/stream/fs/fat.c b/src/stream/fs/fat.c
index 540cac370e..01e4e03cc2 100644
--- a/src/stream/fs/fat.c
+++ b/src/stream/fs/fat.c
@@ -54,7 +54,7 @@ struct fat_superblock
 
 #define FAT_CACHE_SIZE 2048
 
-#if ARCH == 'i386'
+#ifdef __i386
 static __inline__ unsigned long
 log2 (unsigned long word)
 {