diff -Nru mathgl-2.3.3/debian/changelog mathgl-2.3.3/debian/changelog
--- mathgl-2.3.3/debian/changelog	2015-10-05 18:53:57.000000000 +0000
+++ mathgl-2.3.3/debian/changelog	2015-11-28 12:20:26.000000000 +0000
@@ -1,3 +1,9 @@
+mathgl (2.3.3-3+rpi1) stretch-staging; urgency=medium
+
+  * Add #include <QObject> to json/Backend.hpp to fix build failure.
+
+ -- Peter Michael Green <plugwash@raspbian.org>  Sat, 28 Nov 2015 12:01:04 +0000
+
 mathgl (2.3.3-3) unstable; urgency=medium
 
   * Disable need for C++11 support (Closes: #800460)
diff -Nru mathgl-2.3.3/debian/patches/qobject-include.patch mathgl-2.3.3/debian/patches/qobject-include.patch
--- mathgl-2.3.3/debian/patches/qobject-include.patch	1970-01-01 00:00:00.000000000 +0000
+++ mathgl-2.3.3/debian/patches/qobject-include.patch	2015-11-28 12:21:10.000000000 +0000
@@ -0,0 +1,27 @@
+Description:  Add #include <QObject> to json/Backend.hpp to fix build failure.
+Author: Peter Michael Green <plugwash@raspbian.org>
+
+---
+The information above should follow the Patch Tagging Guidelines, please
+checkout http://dep.debian.net/deps/dep3/ to learn about the format. Here
+are templates for supplementary fields that you might want to add:
+
+Origin: <vendor|upstream|other>, <url of original patch>
+Bug: <url in upstream bugtracker>
+Bug-Debian: https://bugs.debian.org/<bugnumber>
+Bug-Ubuntu: https://launchpad.net/bugs/<bugnumber>
+Forwarded: <no|not-needed|url proving that it has been forwarded>
+Reviewed-By: <name and email of someone who approved the patch>
+Last-Update: <YYYY-MM-DD>
+
+Index: mathgl-2.3.3/json/Backend.hpp
+===================================================================
+--- mathgl-2.3.3.orig/json/Backend.hpp
++++ mathgl-2.3.3/json/Backend.hpp
+@@ -1,5 +1,6 @@
+ #pragma once
+ 
++#include <QObject>
+ #include <QStringList>
+ 
+ class Backend : public QObject
diff -Nru mathgl-2.3.3/debian/patches/series mathgl-2.3.3/debian/patches/series
--- mathgl-2.3.3/debian/patches/series	2015-09-05 19:08:44.000000000 +0000
+++ mathgl-2.3.3/debian/patches/series	2015-11-28 12:20:55.000000000 +0000
@@ -1,3 +1,4 @@
 CMakeLists.patch
 udav.patch
 utils.patch
+qobject-include.patch