[gtk/1069-thread-1-glade-received-signal-sigfpe-arithmetic-exception] GtkBox: do not divide by zero on gtk_box_size_allocate_with_center()

[Juan Pablo Ugarte <jpu src gnome org>]

commit 87aed887befdbc537dfadf8d55c775a6bfdd3262
Author: Juan Pablo Ugarte <ugarte endlessm com>
Date:   Sat May 12 11:06:37 2018 -0300

    GtkBox: do not divide by zero on gtk_box_size_allocate_with_center()
    
    https://gitlab.gnome.org/GNOME/gtk/issues/1069

 gtk/gtkbox.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkbox.c b/gtk/gtkbox.c
index 1e9f18d5bd..e97cb1b1f7 100644
--- a/gtk/gtkbox.c
+++ b/gtk/gtkbox.c
@@ -928,8 +928,8 @@ gtk_box_size_allocate_with_center (GtkWidget           *widget,
 
   if (priv->homogeneous)
     {
-      extra[0] = ((box_size - center_size) / 2 - nvis[0] * priv->spacing) / nvis[0];
-      extra[1] = ((box_size - center_size) / 2 - nvis[1] * priv->spacing) / nvis[1];
+      extra[0] = nvis[0] ? ((box_size - center_size) / 2 - nvis[0] * priv->spacing) / nvis[0] : 0;
+      extra[1] = nvis[1] ? ((box_size - center_size) / 2 - nvis[1] * priv->spacing) / nvis[1] : 0;
       extra[0] = MIN (extra[0], extra[1]);
       n_extra_widgets[0] = 0;
     }