@@ -21,12 +21,12 @@
 #import "OFSecureData.h"
 
 #import "OFHashAlreadyCalculatedException.h"
 #import "OFOutOfRangeException.h"
 
-#define DIGEST_SIZE 20
-#define BLOCK_SIZE 64
+static const size_t digestSize = 20;
+static const size_t blockSize = 64;
 
 OF_DIRECT_MEMBERS
 @interface OFSHA1Hash ()
 - (void)of_resetState;
 @end
@@ -99,16 +99,16 @@
 @synthesize calculated = _calculated;
 @synthesize allowsSwappableMemory = _allowsSwappableMemory;
 
 + (size_t)digestSize
 {
-	return DIGEST_SIZE;
+	return digestSize;
 }
 
 + (size_t)blockSize
 {
-	return BLOCK_SIZE;
+	return blockSize;
 }
 
 + (instancetype)hashWithAllowsSwappableMemory: (bool)allowsSwappableMemory
 {
 	return [[[self alloc] initWithAllowsSwappableMemory:
@@ -152,16 +152,16 @@
 	[super dealloc];
 }
 
 - (size_t)digestSize
 {
-	return DIGEST_SIZE;
+	return digestSize;
 }
 
 - (size_t)blockSize
 {
-	return BLOCK_SIZE;
+	return blockSize;
 }
 
 - (id)copy
 {
 	OFSHA1Hash *copy = [[OFSHA1Hash alloc] of_init];