diff --git a/openbox/client.c b/openbox/client.c
index 2e432dbe..f3b4bdac 100644
--- a/openbox/client.c
+++ b/openbox/client.c
@@ -2930,10 +2930,11 @@ void client_try_configure(ObClient *self, gint *x, gint *y, gint *w, gint *h,
 
     /* cap any X windows at the size of an unsigned short */
     *w = MIN(*w,
-             G_MAXUSHORT - self->frame->size.left - self->frame->size.right);
+             (gint)G_MAXUSHORT
+             - self->frame->size.left - self->frame->size.right);
     *h = MIN(*h,
-             G_MAXUSHORT - self->frame->size.top - self->frame->size.bottom);
-
+             (gint)G_MAXUSHORT
+             - self->frame->size.top - self->frame->size.bottom);
 
     /* gets the frame's position */
     frame_client_gravity(self->frame, x, y);