# HG changeset patch
# User sotaro <sotaro.ikeda.g@gmail.com>
# Date 1518739447 -32400
# Node ID 0a84902451470ab29d1f907e91c4fdd78f4b4a2d
# Parent  f4a15e090391fd173dff320ad69c7e2b97ab0dcf
Bug 1438408 - Shutdown RenderThread if it exists r=nical

diff --git a/gfx/ipc/GPUParent.cpp b/gfx/ipc/GPUParent.cpp
--- a/gfx/ipc/GPUParent.cpp
+++ b/gfx/ipc/GPUParent.cpp
@@ -451,17 +451,19 @@ GPUParent::ActorDestroy(ActorDestroyReas
 
   if (mVsyncBridge) {
     mVsyncBridge->Shutdown();
     mVsyncBridge = nullptr;
   }
   dom::VideoDecoderManagerParent::ShutdownVideoBridge();
   CompositorThreadHolder::Shutdown();
   VRListenerThreadHolder::Shutdown();
-  if (gfxVars::UseWebRender()) {
+  // There is a case that RenderThread exists when gfxVars::UseWebRender() is false.
+  // This could happen when WebRender was fallbacked to compositor.
+  if (wr::RenderThread::Get()) {
     wr::RenderThread::ShutDown();
 
     wr::WebRenderAPI::ShutdownExternalLogHandler();
   }
   Factory::ShutDown();
 #if defined(XP_WIN)
   DeviceManagerDx::Shutdown();
 #endif
diff --git a/gfx/thebes/gfxPlatform.cpp b/gfx/thebes/gfxPlatform.cpp
--- a/gfx/thebes/gfxPlatform.cpp
+++ b/gfx/thebes/gfxPlatform.cpp
@@ -1068,17 +1068,19 @@ gfxPlatform::ShutdownLayersIPC()
         }
     } else if (XRE_IsParentProcess()) {
         gfx::VRManagerChild::ShutDown();
         layers::CompositorManagerChild::Shutdown();
         layers::ImageBridgeChild::ShutDown();
         // This has to happen after shutting down the child protocols.
         layers::CompositorThreadHolder::Shutdown();
         gfx::VRListenerThreadHolder::Shutdown();
-        if (gfxVars::UseWebRender()) {
+        // There is a case that RenderThread exists when gfxVars::UseWebRender() is false.
+        // This could happen when WebRender was fallbacked to compositor.
+        if (wr::RenderThread::Get()) {
           wr::RenderThread::ShutDown();
 
           Preferences::UnregisterCallback(WebRenderDebugPrefChangeCallback, WR_DEBUG_PREF);
         }
 
     } else {
       // TODO: There are other kind of processes and we should make sure gfx
       // stuff is either not created there or shut down properly.