1 files changed, 5 insertions, 0 deletions
diff --git a/src/corelib/thread/qthreadpool.cpp b/src/corelib/thread/qthreadpool.cpp
index 9185554b1fb..4d7d7a22500 100644
--- a/src/corelib/thread/qthreadpool.cpp
+++ b/src/corelib/thread/qthreadpool.cpp
@@ -194,6 +194,11 @@ bool QThreadPoolPrivate::tryStart(QRunnable *task)
         ++activeThreads;
 
         thread->runnable = task;
+
+        // Ensure that the thread has actually finished, otherwise the following
+        // start() has no effect.
+        thread->wait();
+        Q_ASSERT(thread->isFinished());
         thread->start(threadPriority);
         return true;
     }