From 5ab6042c04f65ebab363450acc6503ce4290d5c3 Mon Sep 17 00:00:00 2001
From: reuk <reuk@users.noreply.github.com>
Date: Fri, 10 Jul 2020 20:02:50 +0100
Subject: [PATCH] Convolution:  Fix issue where old convolution engines were
 sometimes used after calling prepare

The startThread/stopThread calls were moved to prevent a thread
sanitizer warning about a race on the vtable of Impl.
---
 .../juce_dsp/frequency/juce_Convolution.cpp   | 24 ++++++++++---------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/modules/juce_dsp/frequency/juce_Convolution.cpp b/modules/juce_dsp/frequency/juce_Convolution.cpp
index 8983676570..050aa91bc3 100644
--- a/modules/juce_dsp/frequency/juce_Convolution.cpp
+++ b/modules/juce_dsp/frequency/juce_Convolution.cpp
@@ -77,14 +77,7 @@ class BackgroundMessageQueue  : private Thread
 public:
     explicit BackgroundMessageQueue (int entries)
         : Thread ("Convolution background loader"), queue (entries)
-    {
-        startThread();
-    }
-
-    ~BackgroundMessageQueue() override
-    {
-        stopThread (-1);
-    }
+    {}
 
     using IncomingCommand = FixedSizeFunction<400, void()>;
 
@@ -93,6 +86,9 @@ public:
     // This function is only safe to call from a single thread at a time.
     bool push (IncomingCommand& command) { return queue.push (command); }
 
+    using Thread::startThread;
+    using Thread::stopThread;
+
 private:
     void run() override
     {
@@ -119,9 +115,14 @@ ConvolutionMessageQueue::ConvolutionMessageQueue()
 
 ConvolutionMessageQueue::ConvolutionMessageQueue (int entries)
     : pimpl (std::make_unique<Impl> (entries))
-{}
+{
+    pimpl->startThread();
+}
 
-ConvolutionMessageQueue::~ConvolutionMessageQueue() noexcept = default;
+ConvolutionMessageQueue::~ConvolutionMessageQueue() noexcept
+{
+    pimpl->stopThread (-1);
+}
 
 ConvolutionMessageQueue::ConvolutionMessageQueue (ConvolutionMessageQueue&&) noexcept = default;
 ConvolutionMessageQueue& ConvolutionMessageQueue::operator= (ConvolutionMessageQueue&&) noexcept = default;
@@ -1016,7 +1017,8 @@ public:
     {
         mixer.prepare (spec);
         engineQueue->prepare (spec);
-        installPendingEngine();
+        currentEngine = engineQueue->getEngine();
+        previousEngine = nullptr;
         jassert (currentEngine != nullptr);
     }