diff --git a/lib/select.c b/lib/select.c
index e39174f1a5..83484eeeb3 100644
--- a/lib/select.c
+++ b/lib/select.c
@@ -479,7 +479,7 @@ int Curl_select(int nfds,
       SET_SOCKERRNO(EINVAL);
       return -1;
     }
-    timeout_ms = (timeout->tv_sec * 1000) + (timeout->tv_usec / 1000);
+    timeout_ms = (int)(timeout->tv_sec * 1000) + (int)(timeout->tv_usec / 1000);
   }
   else {
     timeout_ms = -1;