Bug 241382

Description:
html5lib/generated/run-tests19-data.html

Is flaky crash on macOS-AppleSilicon-Big-Sur-Debug-WK2-Tests-EWS in https://ews-build.s3-us-west-2.amazonaws.com/macOS-AppleSilicon-Big-Sur-Debug-WK2-Tests-EWS/460048-32498/results.html

History:
This does not appear in https://results.webkit.org/?suite=layout-tests&test=html5lib%2Fgenerated%2Frun-tests19-data.html&platform=ios&platform=mac&limit=50000

The first instance I can find is https://ews-build.webkit.org/#/builders/60/builds/32363

Crash Log:
No crash log found

stderr:
ASSERTION FAILED: !lookupForWriting(Extractor::extract(entry)).second
/Volumes/Data/worker/macOS-AppleSilicon-Big-Sur-Debug-Build-EWS/build/WebKitBuild/Debug/usr/local/include/wtf/HashTable.h(1054) : WTF::HashTable::ValueType *WTF::HashTable<WebCore::TextRun, WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>, WTF::KeyValuePairKeyExtractor<WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>>, WTF::DefaultHash<WebCore::TextRun>, WTF::HashMap<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>::KeyValuePairTraits, WTF::HashTraits<WebCore::TextRun>>::reinsert(WTF::HashTable::ValueType &&) [Key = WebCore::TextRun, Value = WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>, Extractor = WTF::KeyValuePairKeyExtractor<WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>>, HashFunctions = WTF::DefaultHash<WebCore::TextRun>, Traits = WTF::HashMap<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry>>::KeyValuePairTraits, KeyTraits = WTF::HashTraits<WebCore::TextRun>]
1   0x141fc8674 WTFCrash
2   0x11c0c6fe0 WebCore::JSHTMLHeadElement::createPrototype(JSC::VM&, WebCore::JSDOMGlobalObject&)
3   0x120788320 WTF::HashTable<WebCore::TextRun, WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::KeyValuePairKeyExtractor<WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> > >, WTF::DefaultHash<WebCore::TextRun>, WTF::HashMap<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter>, WTF::DefaultHash<WebCore::TextRun>, WTF::HashTraits<WebCore::TextRun>, WTF::HashTraits<WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::HashTableTraits>::KeyValuePairTraits, WTF::HashTraits<WebCore::TextRun> >::reinsert(WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >&&)
4   0x120787fac WTF::HashTable<WebCore::TextRun, WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::KeyValuePairKeyExtractor<WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> > >, WTF::DefaultHash<WebCore::TextRun>, WTF::HashMap<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter>, WTF::DefaultHash<WebCore::TextRun>, WTF::HashTraits<WebCore::TextRun>, WTF::HashTraits<WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::HashTableTraits>::KeyValuePairTraits, WTF::HashTraits<WebCore::TextRun> >::rehash(unsigned int, WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >*)
5   0x120787918 WTF::HashTable<WebCore::TextRun, WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::KeyValuePairKeyExtractor<WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> > >, WTF::DefaultHash<WebCore::TextRun>, WTF::HashMap<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter>, WTF::DefaultHash<WebCore::TextRun>, WTF::HashTraits<WebCore::TextRun>, WTF::HashTraits<WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >, WTF::HashTableTraits>::KeyValuePairTraits, WTF::HashTraits<WebCore::TextRun> >::expand(WTF::KeyValuePair<WebCore::TextRun, WTF::WeakPtr<WebCore::GlyphDisplayListCache::Entry, WTF::EmptyCounter> >*)