160992 2016-08-18 20:53:36 -0700 Wrong error message for a program that calls a function with arguments that do a getByVal off of undefined 2016-10-13 20:24:00 -0700 1 1 1 Unclassified WebKit JavaScriptCore WebKit Local Build Unspecified Unspecified RESOLVED DUPLICATE 163426 P2 Normal --- 1 saam webkit-unassigned benjamin fpizlo ggaren gskachkov jfbastien joepeck keith_miller mark.lam msaboff oliver sukolsak ticaiolima ysuzuki oldest_to_newest 1221316 0 saam 2016-08-18 20:53:36 -0700 We print the wrong error message in this program: ``` function foo() { let additions = [ [10, 20], //[{}, Symbol()] [{}, {}] ]; let addedAdditions = []; let allItems = []; let map = new Map; map.set('foo', 'bar'); map.set(20, {}); //let item; for (let item of map) { if (item[0] === 20) { map.delete(20); map.set(30, 40); } print(JSON.stringify(item)); let addition = additions.pop(); addedAdditions.push(addition); allItems.push(item); print(addition); map.set(addition[0], addition[1]); } } foo(); ``` We print: Exception: TypeError: undefined is not an object (evaluating 'map.set') even though it's "addition[0]" where the undefined load is happening. 1240085 1 joepeck 2016-10-13 20:24:00 -0700 This is fixed by bug 163426! *** This bug has been marked as a duplicate of bug 163426 ***