let theglobal = 0; for (theglobal = 0; theglobal < 100000; ++theglobal) ; const foo = (ignored, arg1) => { theglobal = arg1; }; for (let j = 0; j < 10000; ++j) { const obj = { set hello(ignored) {}, [theglobal]: 0 }; foo(obj, 'hello'); }