diff --git a/src/devices/cpu/i386/cache.h b/src/devices/cpu/i386/cache.h
index a04f2cacf2e..7dc2e6ad45c 100644
--- a/src/devices/cpu/i386/cache.h
+++ b/src/devices/cpu/i386/cache.h
@@ -8,9 +8,10 @@
 
 /* To test it outside of Mame
 #include <cstdlib>
+#include <cstdint>
 
-typedef unsigned char u8;
-typedef unsigned int u32;
+typedef uint8_t u8;
+typedef uint32_t u32;
 */
 
 enum {