From d6e452ea08df935e886a3b4db63799f2a95f22de Mon Sep 17 00:00:00 2001
From: James Turner <zakalawe@mac.com>
Date: Thu, 29 Jul 2021 15:21:39 +0100
Subject: [PATCH] Fix a ref-count loop in Paticles manager

---
 simgear/scene/model/particles.cxx | 8 ++++++++
 simgear/scene/model/particles.hxx | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/simgear/scene/model/particles.cxx b/simgear/scene/model/particles.cxx
index 8dee9e7f..0c7b774f 100644
--- a/simgear/scene/model/particles.cxx
+++ b/simgear/scene/model/particles.cxx
@@ -516,6 +516,14 @@ void Particles::setupStaticColorComponent(float r1, float g1, float b1, float a1
     staticColorComponents[7] = a2;
 }
 
+ParticlesGlobalManager::~ParticlesGlobalManager()
+{
+    // break a ref-counting cycle
+    if (d->_commonRoot) {
+        d->_commonRoot->removeUpdateCallback(d.get());
+    }
+}
+
 void ParticlesGlobalManager::setWindVector(const osg::Vec3& wind)
 {
     std::lock_guard<std::mutex> g(d->_lock);
diff --git a/simgear/scene/model/particles.hxx b/simgear/scene/model/particles.hxx
index b5af333f..f99ba832 100644
--- a/simgear/scene/model/particles.hxx
+++ b/simgear/scene/model/particles.hxx
@@ -150,7 +150,7 @@ protected:
 class ParticlesGlobalManager
 {
 public:
-    ~ParticlesGlobalManager() = default;
+    ~ParticlesGlobalManager();
 
     static ParticlesGlobalManager* instance();
     static void clear();