function foo(o) { "use strict"; o.f = 42; } noInline(foo); for (var i = 0; i < 100000; ++i) { var o = {}; foo(o); if (o.f != 42) throw "Error: bad result: " + o.f; o = {f:23}; foo(o); if (o.f != 42) throw "Error: bad result: " + o.f; o = {g:12}; foo(o); if (o.f != 42) throw "Error: bad result: " + o.f; } var didThrow; try { var o = {}; Object.freeze(o); foo(o); } catch (e) { didThrow = e; } if (!didThrow || didThrow.toString().indexOf("TypeError:") != 0) throw "Error: didn't throw or threw wrong exception: " + didThrow;