michael@0: // This test case failed a WIP patch. See https://bugzilla.mozilla.org/show_bug.cgi?id=504587#c68
michael@0: 
michael@0: function B() {}
michael@0: B.prototype.x = 1;
michael@0: var d = new B;
michael@0: 
michael@0: var names = ['z', 'z', 'z', 'z', 'z', 'z', 'z', 'x'];
michael@0: for (var i = 0; i < names.length; i++) {
michael@0:     x = d.x;  // guard on shapeOf(d)
michael@0:     d[names[i]] = 2;  // unpredicted shape change
michael@0:     y = d.x;  // guard here is elided
michael@0: }
michael@0: assertEq(y, 2);  // Assertion failed: got 1, expected 2