diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index a31afe713..429cadefc 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -893,8 +893,9 @@ static GDateTime *
 g_date_time_new_from_timeval (GTimeZone      *tz,
                               const GTimeVal *tv)
 {
-  if ((gint64) tv->tv_sec > G_MAXINT64 - 1 ||
-      !UNIX_TO_INSTANT_IS_VALID ((gint64) tv->tv_sec + 1))
+  gint64 tv_sec = tv->tv_sec;
+
+  if (tv_sec > G_MAXINT64 - 1 || !UNIX_TO_INSTANT_IS_VALID (tv_sec + 1))
     return NULL;
 
   return g_date_time_from_instant (tz, tv->tv_usec +