diff --git a/common/uvm32_target.h b/common/uvm32_target.h
index 52277d1..7b1ec8a 100644
--- a/common/uvm32_target.h
+++ b/common/uvm32_target.h
@@ -7,10 +7,10 @@ typedef unsigned long long uint64_t;
 typedef unsigned long uint32_t;
 typedef unsigned short uint16_t;
 typedef unsigned char uint8_t;
-typedef long long int64_t;
-typedef long int32_t;
-typedef short int16_t;
-typedef char int8_t;
+typedef signed long long int64_t;
+typedef signed long int32_t;
+typedef signed short int16_t;
+typedef signed char int8_t;
 
 // <stdbool>
 typedef unsigned char bool;