diff --git a/CommonLibs/Timeval.cpp b/CommonLibs/Timeval.cpp
index 47eebc4..50ce05d 100644
--- a/CommonLibs/Timeval.cpp
+++ b/CommonLibs/Timeval.cpp
@@ -71,8 +71,8 @@
 long Timeval::delta(const Timeval& other) const
 {
 	// 2^31 milliseconds is just over 4 years.
-	long deltaS = other.sec() - sec();
-	long deltaUs = other.usec() - usec();
+	int32_t deltaS = other.sec() - sec();
+	int32_t deltaUs = other.usec() - usec();
 	return 1000*deltaS + deltaUs/1000;
 }