WTF?

Seen in a Safari crash report today:

Thread 0 Crashed: Dispatch queue: com.apple.main-thread 0 com.apple.WebCore 0x00007fff849031b1 bool WTF::HashTable WTF::PassRefPtr (*)(WebCore::SharedBuffer*)>, WTF::PairFirstExtractor WTF::PassRefPtr (*)(WebCore::SharedBuffer*)> >, WebCore::CaseFoldingHash, WTF::PairHashTraits, WTF::HashTraits (*)(WebCore::SharedBuffer*)> >, WTF::HashTraits >::contains WTF::IdentityHashTranslator WTF::PassRefPtr (*)

WTF, indeed.