quartz: Avoid releasing NULL objects

[Chris Robinson]

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From 3f2fb28d816d7f8ba0a0e1e5882c336ac894e9b5 Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat at gmail.com>
Date: Wed, 4 Apr 2007 09:21:58 -0700
Subject: [PATCH] quartz: Avoid releasing NULL objects

---
 dlls/quartz/filtergraph.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/dlls/quartz/filtergraph.c b/dlls/quartz/filtergraph.c
index 8f87870..51ea94a 100644
--- a/dlls/quartz/filtergraph.c
+++ b/dlls/quartz/filtergraph.c
@@ -274,7 +274,10 @@ static ULONG Filtergraph_Release(IFilterGraphImpl *This) {
             IBaseFilter_Release(This->ppFiltersInGraph[i]);
         }
         for (i = 0; i < This->nItfCacheEntries; i++)
-            IUnknown_Release(This->ItfCacheEntries[i].iface);
+        {
+            if (This->ItfCacheEntries[i].iface)
+                IUnknown_Release(This->ItfCacheEntries[i].iface);
+        }
 	IFilterMapper2_Release(This->pFilterMapper2);
 	CloseHandle(This->hEventCompletion);
 	EventsQueue_Destroy(&This->evqueue);
-- 
1.4.4.4