The following layout test fails on Windows (in Debug mode) due to an assertion: accessibility/aria-combobox.html The crash trace is: WTF.dll!WTFCrash() Line 321 C++ > DumpRenderTree.dll!AccessibilityUIElement::showMenu() Line 736 C++ DumpRenderTree.dll!showMenuCallback(const OpaqueJSContext * context, OpaqueJSValue * function, OpaqueJSValue * thisObject, unsigned int argumentCount, const OpaqueJSValue * const * arguments, const OpaqueJSValue * * exception) Line 650 C++ JavaScriptCore.dll!JSC::APICallbackFunction::call<JSC::JSCallbackFunction>(JSC::ExecState * exec) Line 61 C++ JavaScriptCore.dll!JSC::LLInt::handleHostCall(JSC::ExecState * execCallee, JSC::Instruction * pc, JSC::JSValue callee, JSC::CodeSpecializationKind kind) Line 1051 C++ JavaScriptCore.dll!JSC::LLInt::setUpCall(JSC::ExecState * execCallee, JSC::Instruction * pc, JSC::CodeSpecializationKind kind, JSC::JSValue calleeAsValue, JSC::LLIntCallLinkInfo * callLinkInfo) Line 1097 C++ JavaScriptCore.dll!JSC::LLInt::genericCall(JSC::ExecState * exec, JSC::Instruction * pc, JSC::CodeSpecializationKind kind) Line 1159 C++ JavaScriptCore.dll!llint_slow_path_call(JSC::ExecState * exec, JSC::Instruction * pc) Line 1165 C++ JavaScriptCore.dll!llint_entry() Line 7201 Unknown JavaScriptCore.dll!vmEntryToJavaScript() Line 110 Unknown JavaScriptCore.dll!JSC::JITCode::execute(JSC::VM * vm, JSC::ProtoCallFrame * protoCallFrame) Line 77 C++ JavaScriptCore.dll!JSC::Interpreter::execute(JSC::ProgramExecutable * program, JSC::ExecState * callFrame, JSC::JSObject * thisObj) Line 914 C++ JavaScriptCore.dll!JSC::evaluate(JSC::ExecState * exec, const JSC::SourceCode & source, JSC::JSValue thisValue, JSC::JSValue * returnedException) Line 83 C++ WebKit.dll!WebCore::JSMainThreadExecState::evaluate(JSC::ExecState * exec, const JSC::SourceCode & source, JSC::JSValue thisValue, JSC::JSValue * exception) Line 62 C++ WebKit.dll!WebCore::ScriptController::evaluateInWorld(const WebCore::ScriptSourceCode & sourceCode, WebCore::DOMWrapperWorld & world) Line 151 C++ WebKit.dll!WebCore::ScriptController::evaluate(const WebCore::ScriptSourceCode & sourceCode) Line 167 C++ WebKit.dll!WebCore::ScriptElement::executeScript(const WebCore::ScriptSourceCode & sourceCode) Line 301 C++ WebKit.dll!WebCore::ScriptElement::prepareScript(const WTF::TextPosition & scriptStartPosition, WebCore::ScriptElement::LegacyTypeSupport supportLegacyTypes) Line 237 C++ WebKit.dll!WebCore::HTMLScriptRunner::runScript(WebCore::Element * script, const WTF::TextPosition & scriptStartPosition) Line 304 C++ WebKit.dll!WebCore::HTMLScriptRunner::execute(WTF::PassRefPtr<WebCore::Element> scriptElement, const WTF::TextPosition & scriptStartPosition) Line 177 C++ WebKit.dll!WebCore::HTMLDocumentParser::runScriptsForPausedTreeBuilder() Line 197 C++ WebKit.dll!WebCore::HTMLDocumentParser::canTakeNextToken(WebCore::HTMLDocumentParser::SynchronousMode mode, WebCore::PumpSession & session) Line 214 C++ WebKit.dll!WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode mode) Line 259 C++ WebKit.dll!WebCore::HTMLDocumentParser::pumpTokenizerIfPossible(WebCore::HTMLDocumentParser::SynchronousMode mode) Line 167 C++ WebKit.dll!WebCore::HTMLDocumentParser::resumeParsingAfterScriptExecution() Line 497 C++ WebKit.dll!WebCore::HTMLDocumentParser::notifyFinished(WebCore::CachedResource * cachedResource) Line 537 C++ WebKit.dll!WebCore::CachedResource::checkNotify() Line 296 C++ WebKit.dll!WebCore::CachedResource::finishLoading(WebCore::SharedBuffer * __formal) Line 313 C++ WebKit.dll!WebCore::CachedScript::finishLoading(WebCore::SharedBuffer * data) Line 87 C++ WebKit.dll!WebCore::SubresourceLoader::didFinishLoading(double finishTime) Line 366 C++ WebKit.dll!WebCore::ResourceLoader::didFinishLoading(WebCore::ResourceHandle * __formal, double finishTime) Line 503 C++ WebKit.dll!WebCore::SynchronousResourceHandleCFURLConnectionDelegate::didFinishLoading() Line 181 C++ WebKit.dll!WebCore::ResourceHandleCFURLConnectionDelegate::didFinishLoadingCallback(_CFURLConnection * __formal, const void * clientInfo) Line 88 C++ CFNetwork.dll!URLConnectionClient::_clientDidFinishLoading(URLConnectionClient::ClientConnectionEventQueue * preQ) Line 1739 C++ CFNetwork.dll!URLConnectionClient::ClientConnectionEventQueue::processAllEventsAndConsumePayload(XConnectionEventInfo<enum XClientEvent,XClientEventParams> * e, long count) Line 2256 C++ CFNetwork.dll!XConnectionEventQueue<enum XClientEvent,XClientEventParams>::processAllEvents() Line 231 C++ CFNetwork.dll!URLConnectionClient::processEvents() Line 362 C++ CFNetwork.dll!URLConnectionWndProc(HWND__ * hWnd, unsigned int message, unsigned int wParam, long lParam) Line 109 C++ [External Code] DumpRenderTree.dll!runTest(const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & inputLine) Line 1141 C++ DumpRenderTree.dll!main(int argc, const char * * argv) Line 1484 C++ DumpRenderTree.dll!dllLauncherEntryPoint(int argc, const char * * argv) Line 1514 C++ DumpRenderTree.exe!main(int argc, const char * * argv) Line 239 C++ [External Code] The failing assertion is: void AccessibilityUIElement::showMenu() { if (!m_element) return; ASSERT(hasPopup()); m_element->accDoDefaultAction(self()); }