From 19e1dcff23fd925240d40c2cf0ed555a6388d244 Mon Sep 17 00:00:00 2001
From: Emmanuele Bassi <ebassi@gnome.org>
Date: Wed, 25 May 2011 16:49:09 +0100
Subject: [PATCH] framebuffer: Bail out if the viewport has negative size

---
 cogl/cogl-framebuffer.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/cogl/cogl-framebuffer.c b/cogl/cogl-framebuffer.c
index 9dc0fbc6f..efe010e4c 100644
--- a/cogl/cogl-framebuffer.c
+++ b/cogl/cogl-framebuffer.c
@@ -1413,6 +1413,10 @@ _cogl_framebuffer_flush_state (CoglFramebuffer *draw_buffer,
     {
       float gl_viewport_y;
 
+      if (draw_buffer->viewport_width < 0
+          || draw_buffer->viewport_height < 0)
+        return;
+
       /* Convert the Cogl viewport y offset to an OpenGL viewport y offset
        * NB: OpenGL defines its window and viewport origins to be bottom
        * left, while Cogl defines them to be top left.