diff --git a/include/PR/os_internal.h b/include/PR/os_internal.h
index f8368d8eff..d24be55059 100644
--- a/include/PR/os_internal.h
+++ b/include/PR/os_internal.h
@@ -13,8 +13,8 @@ typedef struct __osHwInt {
 #else
 
 /* __osHwInt struct member offsets */
-#define HWINT_CALLBACK 0x00
-#define HWINT_SP       0x04
+#define HWINT_CALLBACK 0x0
+#define HWINT_SP       0x4
 
 /* __osHwInt struct size */
 #define HWINT_SIZE     0x8