JavaScriptCore - GetterSetter Type Confusion During DFG Compilation

The following JavaScript program, found by Fuzzilli and slightly modified, crashes JavaScriptCore built from HEAD and the current stable release /System/Library/Frameworks/JavaScriptCore.framework/Resources/jsc: let notAGetterSetter = whatever: 42; function v2v5 const v10 = Object; if v5 const v1...