LayoutTest inspector/codemirror/prettyprinting-javascript.html is a flaky timeout https://build.webkit.org/builders/Apple%20Yosemite%20Debug%20WK2%20(Tests)/builds/13653 https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=inspector%2Fcodemirror%2Fprettyprinting-javascript.html
Marked as flaky on mac debug in https://trac.webkit.org/r203521
<rdar://problem/27479225>
The bot claims this was a JavaScriptCore ASSERTION: > 13:32:56.245 15300 worker/0 inspector/codemirror/prettyprinting-javascript.html output stderr lines: > 13:32:56.245 15300 ASSERTION FAILED: The Compare should have been eliminated, it is known to be always false. > 13:32:56.245 15300 !masqueradesAsUndefinedWatchpointIsStillValid() || !isKnownCell(operand.node()) > 13:32:56.245 15300 /Volumes/Data/slave/yosemite-debug/build/Source/JavaScriptCore/dfg/DFGSpeculativeJIT64.cpp(219) : void JSC::DFG::SpeculativeJIT::nonSpeculativeNonPeepholeCompareNullOrUndefined(JSC::DFG::Edge) > 13:32:56.245 15300 1 0x1088a4e70 WTFCrash > 13:32:56.245 15300 2 0x107f741e9 JSC::DFG::SpeculativeJIT::nonSpeculativeNonPeepholeCompareNullOrUndefined(JSC::DFG::Edge) > 13:32:56.245 15300 3 0x107f2b471 JSC::DFG::SpeculativeJIT::compare(JSC::DFG::Node*, JSC::MacroAssemblerX86Common::RelationalCondition, JSC::MacroAssemblerX86Common::DoubleCondition, unsigned long (*)(JSC::ExecState*, long long, long long)) > 13:32:56.245 15300 4 0x107f81207 JSC::DFG::SpeculativeJIT::compile(JSC::DFG::Node*) > 13:32:56.245 15300 5 0x107f1883c JSC::DFG::SpeculativeJIT::compileCurrentBlock() > 13:32:56.246 15300 6 0x107f19016 JSC::DFG::SpeculativeJIT::compile() > 13:32:56.246 15300 7 0x107de71e7 JSC::DFG::JITCompiler::compileBody() > 13:32:56.246 15300 8 0x107deac60 JSC::DFG::JITCompiler::compileFunction() > 13:32:56.246 15300 9 0x107ed7a4b JSC::DFG::Plan::compileInThreadImpl(JSC::DFG::LongLivedState&) > 13:32:56.246 15300 10 0x107ed65c2 JSC::DFG::Plan::compileInThread(JSC::DFG::LongLivedState&, JSC::DFG::ThreadData*) > 13:32:56.246 15300 11 0x108011686 JSC::DFG::Worklist::runThread(JSC::DFG::ThreadData*) > 13:32:56.246 15300 12 0x10800f394 JSC::DFG::Worklist::threadFunction(void*) > 13:32:56.246 15300 13 0x108917e49 WTF::createThread(void (*)(void*), void*, char const*)::$_0::operator()() const > 13:32:56.246 15300 14 0x108917e1d void std::__1::__invoke_void_return_wrapper<void>::__call<WTF::createThread(void (*)(void*), void*, char const*)::$_0&>(WTF::createThread(void (*)(void*), void*, char const*)::$_0&&&) > 13:32:56.246 15300 15 0x108917dbc std::__1::__function::__func<WTF::createThread(void (*)(void*), void*, char const*)::$_0, std::__1::allocator<WTF::createThread(void (*)(void*), void*, char const*)::$_0>, void ()>::operator()() > 13:32:56.246 15300 16 0x107f409aa std::__1::function<void ()>::operator()() const > 13:32:56.246 15300 17 0x108916a1e WTF::threadEntryPoint(void*) > 13:32:56.246 15300 18 0x1089184c1 WTF::wtfThreadEntryPoint(void*) > 13:32:56.246 15300 19 0x7fff8d03105a _pthread_body > 13:32:56.246 15300 20 0x7fff8d030fd7 _pthread_body > 13:32:56.246 15300 21 0x7fff8d02e3ed thread_start And it references the Crash Log: <https://build.webkit.org/results/Apple%20Yosemite%20Debug%20WK2%20(Tests)/r203519%20(13653)/com.apple.WebKit.WebContent-crash-log.txt> > Process: com.apple.WebKit.WebContent.Development [18641] > Crashed Thread: 13 DFG Worklist Worker Thread > > Exception Type: EXC_BAD_ACCESS (SIGSEGV) > Exception Codes: KERN_INVALID_ADDRESS at 0x00000000bbadbeef > > Thread 13 Crashed:: DFG Worklist Worker Thread > 0 com.apple.JavaScriptCore 0x00000001088a4e77 WTFCrash + 39 > 1 com.apple.JavaScriptCore 0x0000000107f741e9 JSC::DFG::SpeculativeJIT::nonSpeculativeNonPeepholeCompareNullOrUndefined(JSC::DFG::Edge) + 137 > 2 com.apple.JavaScriptCore 0x0000000107f2b471 JSC::DFG::SpeculativeJIT::compare(JSC::DFG::Node*, JSC::MacroAssemblerX86Common::RelationalCondition, JSC::MacroAssemblerX86Common::DoubleCondition, unsigned long (*)(JSC::ExecState*, long long, long long)) + 929 > 3 com.apple.JavaScriptCore 0x0000000107f81207 JSC::DFG::SpeculativeJIT::compile(JSC::DFG::Node*) + 10279 > 4 com.apple.JavaScriptCore 0x0000000107f1883c JSC::DFG::SpeculativeJIT::compileCurrentBlock() + 1628 > 5 com.apple.JavaScriptCore 0x0000000107f19016 JSC::DFG::SpeculativeJIT::compile() + 182 > 6 com.apple.JavaScriptCore 0x0000000107de71e7 JSC::DFG::JITCompiler::compileBody() + 55 > 7 com.apple.JavaScriptCore 0x0000000107deac60 JSC::DFG::JITCompiler::compileFunction() + 1424 > 8 com.apple.JavaScriptCore 0x0000000107ed7a4b JSC::DFG::Plan::compileInThreadImpl(JSC::DFG::LongLivedState&) + 3867 > 9 com.apple.JavaScriptCore 0x0000000107ed65c2 JSC::DFG::Plan::compileInThread(JSC::DFG::LongLivedState&, JSC::DFG::ThreadData*) + 386 > 10 com.apple.JavaScriptCore 0x0000000108011686 JSC::DFG::Worklist::runThread(JSC::DFG::ThreadData*) + 806 > 11 com.apple.JavaScriptCore 0x000000010800f394 JSC::DFG::Worklist::threadFunction(void*) + 36 > 12 com.apple.JavaScriptCore 0x0000000108917e49 WTF::createThread(void (*)(void*), void*, char const*)::$_0::operator()() const + 25 > 13 com.apple.JavaScriptCore 0x0000000108917e1d void std::__1::__invoke_void_return_wrapper<void>::__call<WTF::createThread(void (*)(void*), void*, char const*)::$_0&>(WTF::createThread(void (*)(void*), void*, char const*)::$_0&&&) + 45 > 14 com.apple.JavaScriptCore 0x0000000108917dbc std::__1::__function::__func<WTF::createThread(void (*)(void*), void*, char const*)::$_0, std::__1::allocator<WTF::createThread(void (*)(void*), void*, char const*)::$_0>, void ()>::operator()() + 44 > 15 com.apple.JavaScriptCore 0x0000000107f409aa std::__1::function<void ()>::operator()() const + 26 > 16 com.apple.JavaScriptCore 0x0000000108916a1e WTF::threadEntryPoint(void*) + 158 > 17 com.apple.JavaScriptCore 0x00000001089184c1 WTF::wtfThreadEntryPoint(void*) + 289 > 18 libsystem_pthread.dylib 0x00007fff8d03105a _pthread_body + 131 > 19 libsystem_pthread.dylib 0x00007fff8d030fd7 _pthread_start + 176 > 20 libsystem_pthread.dylib 0x00007fff8d02e3ed thread_start + 13