Merge remote-tracking branch 'origin/4.7' into qt-master-from-4.7

Conflicts:
	src/opengl/gl2paintengineex/qpaintengineex_opengl2.cpp
	src/opengl/gl2paintengineex/qtextureglyphcache_gl.cpp
	src/opengl/gl2paintengineex/qtextureglyphcache_gl_p.h

1 files changed, 38 insertions, 0 deletions

diff --git a/tests/auto/qmutex/tst_qmutex.cpp b/tests/auto/qmutex/tst_qmutex.cpp
index 3c4c7674de..ea983cbd10 100644
--- a/tests/auto/qmutex/tst_qmutex.cpp
+++ b/tests/auto/qmutex/tst_qmutex.cpp
@@ -67,6 +67,7 @@ private slots:
     void lock_unlock_locked_tryLock();
     void stressTest();
     void tryLockRace();
+    void qtbug16115_trylock();
 };
 
 static const int iterations = 100;
@@ -464,5 +465,42 @@ void tst_QMutex::tryLockRace()
     TryLockRaceThread::mutex.unlock();
 }
 
+static volatile int qtbug16115_trylock_counter;
+
+void tst_QMutex::qtbug16115_trylock()
+{
+    //Used to deadlock on unix
+    struct TrylockThread : QThread {
+        TrylockThread(QMutex &mut) : mut(mut) {}
+        QMutex &mut;
+        void run() {
+            for (int i = 0; i < 1000000; ++i) {
+                if (mut.tryLock(0)) {
+                    Q_ASSERT((++qtbug16115_trylock_counter) == 1);
+                    Q_ASSERT((--qtbug16115_trylock_counter) == 0);
+                    mut.unlock();
+                }
+            }
+        }
+    };
+    QMutex mut;
+    TrylockThread t1(mut);
+    TrylockThread t2(mut);
+    TrylockThread t3(mut);
+    t1.start();
+    t2.start();
+    t3.start();
+
+    for (int i = 0; i < 1000000; ++i) {
+        mut.lock();
+        Q_ASSERT((++qtbug16115_trylock_counter) == 1);
+        Q_ASSERT((--qtbug16115_trylock_counter) == 0);
+        mut.unlock();
+    }
+    t1.wait();
+    t2.wait();
+    t3.wait();
+}
+
 QTEST_MAIN(tst_QMutex)
 #include "tst_qmutex.moc"