ufuzz failure

[alexlamsl]

// original code
// (beautified)
var _calls_ = 10, a = 100, b = 10, c = 0;

function f0() {
    {
        var expr1 = [];
        for (const key1 of expr1) {
            c = 1 + c;
            var yield = expr1[key1];
            var a = 0 === 1 ? a : b, NaN = ((c = c + 1) + void function() {
                c = c + 1;
            }() || 0).toString()[b = a];
        }
    }
    c = c + 1;
}

export var await = f0(typeof f0 == "function" && --_calls_ >= 0 && f0(!((await && (await[c = 1 + c, 
(23..toString() == Infinity) % ("number" * {}), ([ , 0 ][1], 4) + "function" * 24..toString()] %= "number" !== Infinity)) * ([] ^ 23..toString()) !== (this >>> "undefined" ^ -1 - "b")), 38..toString(), /[abc4]/.test(((await = await = b--) || b || 5).toString())));

console.log(null, a, b, c, Infinity, NaN, undefined);

// uglified code
// (beautified)
var o, n = 10, f = 0;

function f0() {
    for (const o of []) {
        f = 1 + f, o, f += 1, f += 1;
    }
    f += 1;
}

o = f0(f0(o && (o[f = 1 + f, NaN] %= !0), ((o = n--) || n || 5).toString())), console.log(null, 100, 10, f, Infinity, NaN, void 0);

export {
    o as await
};

original result:
null 100 9 2 Infinity NaN undefined

uglified result:
null 100 10 2 Infinity NaN undefined

// reduced test case (output will differ)

// (beautified)
var b = 0;

function f0() {
    var expr1 = [];
    for (const key1 of expr1) {
        var a = b, NaN = b = a;
    }
}

f0 && f0((b-- || b).toString());

console.log(b);
// output: -1
// 
// minify: 0
// 
// options: {
//   "compress": {
//     "hoist_vars": true,
//     "keep_infinity": true,
//     "passes": 1000000,
//     "unsafe": true
//   },
//   "keep_fargs": true,
//   "keep_fnames": true,
//   "toplevel": true,
//   "mangle": {
//     "v8": true
//   },
//   "output": {
//     "v8": true
//   },
//   "validate": true
// }

minify(options):
{
  "compress": {
    "hoist_vars": true,
    "keep_infinity": true,
    "passes": 1000000,
    "unsafe": true
  },
  "keep_fargs": true,
  "keep_fnames": true,
  "toplevel": true,
  "mangle": {
    "v8": true
  },
  "output": {
    "v8": true
  }
}

Suspicious compress options:
  collapse_vars
  conditionals
  evaluate
  hoist_vars
  passes
  pure_getters
  reduce_vars
  unsafe
  unused

Suspicious options:
  toplevel