[gtk+] label: Fix gcc warning

[Benjamin Otte <otte src gnome org>]

commit 64a1f30468dad3016899a2dc28206f4d4792d887
Author: Benjamin Otte <otte redhat com>
Date:   Fri Aug 23 18:24:20 2013 +0200

    label: Fix gcc warning

 gtk/gtklabel.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtklabel.c b/gtk/gtklabel.c
index 0a1b32c..56610b4 100644
--- a/gtk/gtklabel.c
+++ b/gtk/gtklabel.c
@@ -6608,7 +6608,7 @@ gtk_label_set_lines (GtkLabel *label,
 gint
 gtk_label_get_lines (GtkLabel *label)
 {
-  g_return_if_fail (GTK_IS_LABEL (label));
+  g_return_val_if_fail (GTK_IS_LABEL (label), -1);
 
   return label->priv->lines;
 }