diff --git a/core/SAL/bochs/BochsConfig.hpp b/core/SAL/bochs/BochsConfig.hpp
index 3481a7b0..549388e1 100644
--- a/core/SAL/bochs/BochsConfig.hpp
+++ b/core/SAL/bochs/BochsConfig.hpp
@@ -13,10 +13,11 @@ namespace sal
 typedef bx_address guest_address_t; //!< the guest memory address type
 typedef Bit8u*     host_address_t;  //!< the host memory address type
 #if BX_SUPPORT_X86_64
-  typedef Bit64u register_data_t;   //!< register data type (64 bit)
+  typedef Bit64u   register_data_t; //!< register data type (64 bit)
 #else
-  typedef Bit32u register_data_t;   //!< register data type (32 bit)
+  typedef Bit32u   register_data_t; //!< register data type (32 bit)
 #endif
+typedef int        timer_t;         //!< type of timer IDs
 
 };
 
diff --git a/core/SAL/ovp/OVPConfig.hpp b/core/SAL/ovp/OVPConfig.hpp
index 91ec5eef..d641b7d8 100644
--- a/core/SAL/ovp/OVPConfig.hpp
+++ b/core/SAL/ovp/OVPConfig.hpp
@@ -1,16 +1,16 @@
 #ifndef __OVP_CONFIG_HPP__
   #define __OVP_CONFIG_HPP__
 
-
 // Type definitions and configuration settings for
 // the OVP simulator.
  
 namespace sal
 {
 
-typedef uint32_t guest_address_t; //!< the guest memory address type
-typedef uint8_t*     host_address_t;  //!< the host memory address type
-typedef uint32_t register_data_t;   //!< register data type (32 bit)
+typedef uint32_t guest_address_t;  //!< the guest memory address type
+typedef uint8_t* host_address_t;   //!< the host memory address type
+typedef uint32_t register_data_t;  //!< register data type (32 bit)
+typedef int      timer_t;          //!< type of timer IDs
 
 };