diff --git a/src/structs.h b/src/structs.h
index 5de3a68..97601af 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -364,7 +364,7 @@
 /*
  * structures used in undo.c
  */
-#if SIZEOF_INT > 2
+#if VIM_SIZEOF_INT > 2
 # define ALIGN_LONG	/* longword alignment and use filler byte */
 # define ALIGN_SIZE (sizeof(long))
 #else
@@ -1094,7 +1094,7 @@
 typedef long_u hash_T;		/* Type for hi_hash */
 
 
-#if SIZEOF_INT <= 3		/* use long if int is smaller than 32 bits */
+#if VIM_SIZEOF_INT <= 3		/* use long if int is smaller than 32 bits */
 typedef long	varnumber_T;
 #else
 typedef int	varnumber_T;