From aa2e03e6ff1138e168b47a2f155d5d099b050d95 Mon Sep 17 00:00:00 2001
From: Thomas Tuegel <ttuegel@gmail.com>
Date: Mon, 25 Jan 2016 06:31:06 -0600
Subject: [PATCH] qt55.qtbase: upstream patch for backing store issue

The included patch from upstream fixes the issue described here:
https://bugreports.qt.io/browse/QTBUG-48321
The backing store of certain widgets was being improperly invalidated,
leading to display bugs in, e.g. VLC.

This patch is included in Qt 5.6, so we should remove it when we
upgrade.
---
 pkgs/development/libraries/qt-5/5.5/qtbase/default.nix | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/pkgs/development/libraries/qt-5/5.5/qtbase/default.nix b/pkgs/development/libraries/qt-5/5.5/qtbase/default.nix
index 24e5ccb36f37..e6927ffb9ca4 100644
--- a/pkgs/development/libraries/qt-5/5.5/qtbase/default.nix
+++ b/pkgs/development/libraries/qt-5/5.5/qtbase/default.nix
@@ -26,6 +26,12 @@
 let
   inherit (srcs.qt5) version;
   system-x86_64 = lib.elem stdenv.system lib.platforms.x86_64;
+
+  dontInvalidateBacking = fetchurl {
+    url = "https://codereview.qt-project.org/gitweb?p=qt/qtbase.git;a=patch;h=0f68f8920573cdce1729a285a92ac8582df32841;hp=24c50f8dcf7fa61ac3c3d4d6295c259a104a2b8c";
+    name = "qtbug-48321-dont-invalidate-backing-store.patch";
+    sha256 = "07vnndmvri73psz0nrs2hg0zw2i4b1k1igy2al6kwjbp7d5xpglr";
+  };
 in
 
 stdenv.mkDerivation {
@@ -49,6 +55,10 @@ stdenv.mkDerivation {
 
   postPatch =
     ''
+      cd qtbase
+      patch -p1 <${dontInvalidateBacking}
+      cd ..
+
       substituteInPlace configure --replace /bin/pwd pwd
       substituteInPlace qtbase/configure --replace /bin/pwd pwd
       substituteInPlace qtbase/src/corelib/global/global.pri --replace /bin/ls ${coreutils}/bin/ls