qedit: Return E_POINTER from Timeline_QueryInterface if ppv is NULL.

dlls/qedit/tests/timeline.c

@@ -29,7 +29,7 @@ static void test_timeline(void)
     HRESULT hr;
     IAMTimeline *timeline = NULL;
     IAMTimeline *timeline2 = (IAMTimeline *)0xdeadbeef;
-    IAMTimelineObj *obj;
+    IAMTimelineObj *obj = (IAMTimelineObj *)0xdeadbeef;
     IAMTimelineObj obj_iface;
     TIMELINE_MAJOR_TYPE type;
 
@@ -37,6 +37,13 @@ static void test_timeline(void)
     ok(hr == S_OK || broken(hr == REGDB_E_CLASSNOTREG), "CoCreateInstance failed: %08x\n", hr);
     if (!timeline) return;
 
+    hr = IAMTimeline_QueryInterface(timeline, &IID_IAMTimelineObj, NULL);
+    ok(hr == E_POINTER, "Expected E_POINTER got %08x\n", hr);
+
+    hr = IAMTimeline_QueryInterface(timeline, &IID_IAMTimelineObj, (void **)&obj);
+    ok(hr == E_NOINTERFACE, "Expected E_NOINTERFACE got %08x\n", hr);
+    ok(!obj, "Expected NULL got %p\n", obj);
+
     hr = IAMTimeline_CreateEmptyNode(timeline, NULL, 0);
     ok(hr == E_POINTER, "Expected E_POINTER got %08x\n", hr);
 

dlls/qedit/timeline.c

@@ -70,6 +70,9 @@ static HRESULT WINAPI Timeline_QueryInterface(IUnknown *iface, REFIID riid, void
 
     TRACE("(%p)->(%s %p)\n", This, debugstr_guid(riid), ppv);
 
+    if (!ppv)
+        return E_POINTER;
+
     *ppv = NULL;
     if (IsEqualIID(riid, &IID_IUnknown))
         *ppv = &This->IUnknown_inner;