diff --git a/src/system/system.h b/src/system/system.h
index 1dfbe3f..0a995ca 100644
--- a/src/system/system.h
+++ b/src/system/system.h
@@ -3,9 +3,9 @@
 
 #ifndef SIZE_TYPE
 #ifdef ARCH_32
-#define SIZE_TYPE unsigned int
-#else
 #define SIZE_TYPE unsigned long
+#else
+#define SIZE_TYPE unsigned long long
 #endif
 #endif