michael@0: 
michael@0: var counter = 0;
michael@0: var x = { toString: function() { counter++; } };
michael@0: var y = {};
michael@0: 
michael@0: for (var i = 0; i < 50; i++)
michael@0:   ++y[x];
michael@0: 
michael@0: // :FIXME: bug 672076
michael@0: //assertEq(counter, 50);