148681 2015-09-01 10:11:12 -0700 Functions with non-simple parameter list should have poisoned arguments.callee and arguments.caller (even outside strict mode) 2020-12-11 22:24:53 -0800 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 217574 P2 Normal --- 1 claude.pache webkit-unassigned ashvayka oldest_to_newest 1122563 0 claude.pache 2015-09-01 10:11:12 -0700 For example: (function (x = 1) { return arguments.callee })() // should throw, even in sloppy mode For reference, see step 22 of: http://www.ecma-international.org/ecma-262/6.0/#sec-functiondeclarationinstantiation In short, the spec recognizes two types of Arguments objects: * mapped Arguments object, used for sloppy-mode simple-parameter-list functions; * unmapped Arguments object with poisoned `callee`/`caller`, used for anything else. 1714236 1 ashvayka 2020-12-11 22:24:53 -0800 `arguments.caller` poisoned getter was removed from the spec: please see note 5 of https://tc39.es/ecma262/#sec-arguments-exotic-objects. `arguments.callee` poisoned getter for sloppy functions with non-simple parameter list was implemented in r268323. ^ test262 case: https://test262.report/browse/built-ins/ThrowTypeError/unique-per-realm-non-simple.js. *** This bug has been marked as a duplicate of bug 217574 ***