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 // Force recognition of a known-constant.

 var push = Array.prototype.push;

 function f(arr)

 {

   // Push an actual constant to trigger JIT-inlining of the effect of the push.

   push.call(arr, 99);

 }

 function basic(out)

 {

   // Create an array of arrays, to be iterated over for [].push-calling.  We

   // can't just loop on push on a single array with non-writable length because

   // push throws when called on an array with non-writable length.

   var arrs = out.arrs = [];

   for (var i = 0; i < 100; i++)

     arrs.push([]);

   // Use a much-greater capacity than the eventual non-writable length.

   var a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15];

   Object.defineProperty(a, "length", { writable: false, value: 6 });

   arrs.push(a);

   for (var i = 0, sz = arrs.length; i < sz; i++)

   {

     var arr = arrs[i];

     f(arr);

   }

 }

 var obj = {};

 var arrs, a;

 try

 {

   basic(obj);

   throw new Error("didn't throw!");

 }

 catch (e)

 {

   assertEq(e instanceof TypeError, true, "expected TypeError, got " + e);

   arrs = obj.arrs;

   assertEq(arrs.length, 101);

   for (var i = 0; i < 100; i++)

   {

     assertEq(arrs[i].length, 1, "unexpected length for arrs[" + i + "]");

     assertEq(arrs[i][0], 99, "bad element for arrs[" + i + "]");

   }

   a = arrs[100];

   assertEq(a.hasOwnProperty(6), false);

   assertEq(a[6], undefined);

   assertEq(a.length, 6);

 }