ufuzz failure

[alexlamsl]

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

try {
    {
        var brake2 = 5;
        do {
            {
                var a_2 = function f0(await_1) {
                    async function f1() {
                        function f2() {
                            c = 1 + c, await_1 /= ([ , 0 ][1] <= false) + (await_1 && (await_1[c = 1 + c, 
                            (await_1 += (24..toString() && 1) < (-3 & Infinity)) == void (await_1 && (await_1[c = 1 + c, 
                            "b" < 23..toString() != (await_1 && ({
                                0: await_1.null
                            } = {
                                0: [ , 0 ][1] !== 25
                            })) | "a" % "bar" - (23..toString() >> 23..toString())] += [ , 0 ][1] ^ "function"))] &= -0 | "object")) in (([ , 0 ].length === 2) > "function") * (await_1 = true <= this);
                            c = 1 + c, ([ , 0 ][1] || "a", +3) - ((false !== 38..toString()) >>> (1 !== 25));
                        }
                        var a_2 = f2();
                    }
                    var foo_1 = f1(null in [ (c = 1 + c, (foo_1 += (-3 & "b") * (1 * "undefined")) ^ (false == 23..toString()) >= (22 > 4)), (c = 1 + c, 
                    ((-5 || -0) == (false | 4)) <= (foo_1 && (foo_1.var += [ , 0 ][1] % "b")) - (-1 - 23..toString())), (c = 1 + c, 
                    +("foo" < 2) > ("" / 24..toString() & /[a2][^e]+$/ >= 3)), (c = 1 + c, 
                    await_1 && (await_1.get = -([] >> false) & ~(NaN > -1))), (c = 1 + c, 
                    (5 === "object" == "object" - /[a2][^e]+$/) >> ~("foo" ^ null)) ]);
                    function f3() {
                        if (delete b) {
                        } else {
                            c = 1 + c, ((c = c + 1, "number") ^ 1 % this) % (c = c + 1, 
                            "b" | 2);
                        }
                        {
                            var brake9 = 5;
                            do {
                                switch (c = 1 + c, (4 % "number" && (c = c + 1, 
                                38..toString())) > ("function" >= "b" | (foo_1 && (foo_1[c = 1 + c, 
                                ("undefined" && Infinity) * (3 == 1) < (5 >= 4 && ([ , 0 ].length === 2) > 38..toString())] += 22 !== 25)))) {
                                  default:
                                    ;

                                  case c = 1 + c, ((-5 | 22) << 2 / this) / +(38..toString() > 1):
                                    ;

                                  case c = 1 + c, +((undefined | [ , 0 ].length === 2) + ("b" != -1)):
                                    ;

                                  case c = 1 + c, (2 >> NaN > (-3 < -5)) / ("undefined" << 4 ^ "bar" === /[a2][^e]+$/):
                                    ;
                                    break;
                                }
                            } while (a++ + (await_1 && await_1[c = 1 + c, (await_1 && (await_1.static += NaN ^ "object" ^ 25 & 2)) <= (([ , 0 ].length === 2 === []) < -2 / "bar")]) && --brake9 > 0);
                        }
                    }
                    var await_1_1 = f3(...[], "a");
                    function f4(foo_1, bar_1, foo_1) {
                        for (var brake11 = 5; (c = c + 1) + (typeof f3 == "function" && --_calls_ >= 0 && f3`${c = 1 + c, 
                        (1 <= 4) / (-2 <= NaN) >= ("undefined" < true & 25 >>> -0)}${c = 1 + c, 
                        ((foo_1 && (foo_1[c = 1 + c, (38..toString() > "c" || [] < -3) < (2 ^ "" ^ undefined + -0)] = Infinity < true)) <= (25 > 22)) % (2 >= 2 !== ([] != {}))}${c = 1 + c, 
                        (22 << undefined && [] <= "c") ^ Infinity < 23..toString() != (3 && true)}`) && brake11 > 0; --brake11) {}
                    }
                    var await_1 = f4();
                }("b");
            }
        } while (a++ + ("a" in {
            c: a++ + (a_2 && a_2[((c = c + 1) + (a_2 && a_2[(c = c + 1) + (typeof b_2 != "crap")]) || 0).toString()[--b + (a_2 = a_2 && typeof a_2.c == "function" && --_calls_ >= 0 && (-0 in [ typeof b_1 != "crap", void b, (c = c + 1) + (typeof f1 == "function" && --_calls_ >= 0 && f1(25, 0)) ], 
            a_2.c)(-2, -5, Infinity))]]),
            0: (c = c + 1) + (typeof c == "symbol") ? --b + a_2 : typeof a_2 == "function" && --_calls_ >= 0 && a_2(a++ + {
                done: -1 in {
                    get: (c = 1 + c, (3 & false) >> ("function" !== 2) | (a_2 && (a_2.value = -4 && [ , 0 ][1]), 
                    a_2 && (a_2[c = 1 + c, ("a" >= null !== (a_2 && (a_2[c = 1 + c, 
                    (a_2 &= Infinity && []) + (-0 << 2) - (NaN + ([ 3n ][0] > 2) != ("undefined" == "bar"))] += "function" != false))) * (a_2 && (a_2[a++] &= (a_2 = 5 && -2) * ({} ^ "")))] **= -3 == -3))),
                    1.5(bar_1, bar_2) {
                        bar_1 %= super.static;
                        this[c = 1 + c, (c = c + 1, 5) / (-1 > "b") & (c = c + 1, 
                        c = c + 1, -3)] += /[a2][^e]+$/ ^ 38..toString();
                    },
                    Infinity: (c = 1 + c, "object" / 3 > ("b" | [ , 0 ][1]) && -5 >>> 2 >= ({} ^ "b"))
                },
                done: a++ + /[abc4]/.test(((c = 1 + c, (null <= ([ , 0 ].length === 2)) * (a_2 && (a_2[c = 1 + c, 
                (4, "a") % (-4 % NaN) ^ 25 !== "number" == (a_2 && (a_2[c = 1 + c, 
                "" < false !== (true != -4) || +("c" !== "number")] += "object" <= undefined))] = [ , 0 ][1] != "foo")) & void -5 >>> NaN / -1) || b || 5).toString()),
                [a++ + /[abc4]/.test(((c = 1 + c, ("b" >= NaN) / ("object" >>> -5) << ([ , 0 ][1] >= undefined) + delete -1) || b || 5).toString())]: (c = c + 1) + (typeof a_2 == "function" && --_calls_ >= 0 && a_2()),
                0: --b + ((c = 1 + c, (false !== Infinity !== -2 >> "bar") ** ("undefined" >>> {} >= ("function" | NaN))) ? (c = 1 + c, 
                (("c" ^ []) !== -2 - "function") >>> (c = c + 1, /[a2][^e]+$/ * 22)) : (c = 1 + c, 
                "a" >>> 24..toString() >> (NaN != Number(0xdeadn << 16n | 0xbeefn)) <= ((24..toString(), 
                "bar") ^ 2 << 2))),
                in: (c = 1 + c, ("c" < 25, "object" === 1) | ([] ^ 5) == "b" > -0) ? (c = 1 + c, 
                (5 ^ "") + -1 % 24..toString() ^ ("c" ^ "bar" ^ "undefined" <= -0)) : (c = 1 + c, 
                (a_2 <<= (4 ^ 5) - (22 == undefined)) <= ((a_2 = -4 * "function") >= (true ^ "a")))
            } ? (c = c + 1) + (0 === 1 ? a : b) : function arguments(a_2) {
                {
                    return;
                    c = 1 + c, (a_2 && (a_2.in ^= null - "c" === ("a" || "function"))) == ("" || "c") <= [] >>> -5;
                }
                try {
                    c = 1 + c, ((a_2 && (a_2[c = 1 + c, ((arguments && (arguments.get = 2 && this)) ^ delete "undefined") % (([ , 0 ].length === 2) >= "a" ^ null != -1)] = {} << [ , 0 ][1])) <= (false < "function")) >>> (4 >> -1 > (arguments && (arguments.foo = this <= "c")));
                } catch (yield_2) {
                } finally {
                }
                if (c = 1 + c, (a_2 && ([ a_2.value ] = [ {} == true ])) <= ({}, 
                [ , 0 ][1]) != false >>> [] < (-1 == "number")) {
                    c = 1 + c, (c = c + 1, "b", -4) && 24..toString() >>> "b" >> ("c" === 2);
                }
            }, "object", {
                a_2: a_2,
                static: {
                    in: (c = 1 + c, (/[a2][^e]+$/ == 24..toString()) >> ("object" < 22), 
                    ("number" == "bar") / ("number" | this))
                }[a++ + (a_2 && typeof a_2.c == "function" && --_calls_ >= 0 && (c = 1 + c, 
                c = c + 1, ("b" && -5) >= (this === 4), a_2.c)(""))],
                "": typeof f1 == "function" && --_calls_ >= 0 && f1(),
                c: a_2 && typeof a_2.undefined == "function" && --_calls_ >= 0 && a_2.undefined`${c = 1 + c, 
                c = c + 1, -1 != false !== (a_2 && ({
                    then: a_2[c = 1 + c, c = c + 1, a_2 && (a_2.next += (25 << 25) + ("b", 
                    Infinity))]
                } = {
                    then: {} || [ , 0 ][1]
                }))}
${c = 1 + c, c = c + 1, a_2 && (a_2.in = (-3 ^ -1) != (-3 ^ undefined))}
${c = 1 + c, "" % "b" ^ undefined << 24..toString() || (a_2 += (24..toString() != "") % (4 >= false))}
${c = 1 + c, (c = c + 1, "function", 25) !== (null >>> 38..toString() | [] < "undefined")}`,
                next: a++ + (1 === 1 ? a : b)
            }[/[abc4]/g.exec(((c = c + 1) + (b = a) || b || 5).toString())]),
            ...--b + (b-- || 5).toString()[--b + (a_2 && a_2.b)],
            b: a++ + delete b
        }) && --brake2 > 0);
    }
} catch (a_2) {
    {
        var a = function f5([], arguments_1) {
            {
                var brake21 = 5;
                L10307: do {
                    {
                        var yield_1 = function bar_1() {
                            {
                                c = 1 + c, ((-5 && -2) << "a" * 4) - ("foo" ^ -4 && true <= "object");
                                c = 1 + c, delete (24..toString() % 0 | 25 < Number(0xdeadn << 16n | 0xbeefn));
                                c = 1 + c, (22 % -2 | "a" < 2) % (arguments_1 && (arguments_1.foo = [] > 2 ^ ([ , 0 ].length === 2, 
                                22)));
                                c = 1 + c, c = c + 1, ("function" === undefined) / (0 - this);
                            }
                            c = c + 1;
                        }(null);
                    }
                } while (a++ + ++a && --brake21 > 0);
            }
            {
                c = c + 1;
            }
        }([], a_2, b--);
    }
} finally {}

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

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

try {
    var brake2 = 5;
    do {
        var a_2 = function(await_1) {
            var foo_1 = async function() {
                (function() {
                    c = 1 + c, await_1 /= !0 + (await_1 && (await_1[c = 1 + c, (await_1 += (24..toString() && 1) < 0) == void (await_1 && (await_1[c = 1 + c, 
                    "b" < 23..toString() != (await_1 && ({
                        0: await_1.null
                    } = {
                        0: !0
                    })) | NaN - (23..toString() >> 23..toString())] += 0))] &= 0)) in ("function" < (2 === [ , 0 ].length)) * (!0 <= this), 
                    c = 1 + c, 38..toString();
                })();
            }((c = 1 + c, foo_1 += NaN, 23..toString(), c = 1 + c, foo_1 && (foo_1.var += NaN), 
            23..toString(), c = 1 + c, 24..toString(), c = 1 + c, await_1 && (await_1.get = -1 & -([] >> !1)), 
            c = 1 + c));
            function f3() {
                delete b || (c = (c = 1 + c) + 1 + 1);
                var brake9 = 5;
                do {
                    switch (c = 1 + c, (!0 | (foo_1 && (foo_1[c = 1 + c, NaN < ((2 === [ , 0 ].length) > 38..toString())] += !0))) < NaN) {
                      default:
                      case c = 1 + c, (-1 << 2 / this) / (1 < 38..toString()):
                      case c = 1 + c, (void 0 | 2 === [ , 0 ].length) + !0:
                      case c = 1 + c, 1 / 0:
                    }
                } while (a++ + (await_1 && await_1[c = 1 + c, (await_1 && (await_1.static += 0)) <= ((2 === [ , 0 ].length === []) < NaN)]) && 0 < --brake9);
            }
            f3();
            await_1 = function(foo_1, foo_1) {
                for (var brake11 = 5; (c += 1) + (0 <= --_calls_ && f3`${c = 1 + c, 
                !0}${c = 1 + c, ((foo_1 && (foo_1[c = 1 + c, ("c" < 38..toString() || [] < -3) < 2] = !1)) <= !0) % (!0 != ([] != {}))}${c = 1 + c, 
                [] <= "c" ^ 1 / 0 < 23..toString() != !0}`) && 0 < brake11; --brake11) {}
            }();
        }("b");
    } while (a++ + ("a" in {
        c: a++ + (a_2 && a_2[((c += 1) + (a_2 && a_2[(c += 1) + ("crap" != typeof b_2)]) || 0).toString()[--b + (a_2 = a_2 && "function" == typeof a_2.c && 0 <= --_calls_ && (c += 1, 
        "function" == typeof f1 && 0 <= --_calls_ && f1(25, 0), a_2.c)(-2, -5, 1 / 0))]]),
        0: (c += 1) + ("symbol" == typeof c) ? --b + a_2 : "function" == typeof a_2 && 0 <= --_calls_ && a_2(a++ + {
            done: -1 in {
                get: (c = 1 + c, 0 | (a_2 && (a_2.value = 0), a_2 && (a_2[c = 1 + c, 
                (!1 !== (a_2 && (a_2[c = 1 + c, (a_2 &= []) - (NaN + (2 < 3n) != 0)] += !0))) * (a_2 && (a_2[a++] &= (a_2 = -2) * ("" ^ {})))] **= !0))),
                1.5(bar_1, bar_2) {
                    super.static, this[c = 1 + c, 1 / 0 & (c = (c += 1) + 1 + 1, 
                    -3)] += /[a2][^e]+$/ ^ 38..toString();
                },
                Infinity: (c = 1 + c, !1)
            },
            done: a++ + /[abc4]/.test((c = 1 + c, ((null <= (2 === [ , 0 ].length)) * (a_2 && (a_2[c = 1 + c, 
            NaN ^ 1 == (a_2 && (a_2[c = 1 + c, !0] += !1))] = !0)) & 0 || b || 5).toString())),
            [a++ + /[abc4]/.test((c = 1 + c, (b || 5).toString()))]: (c += 1) + ("function" == typeof a_2 && 0 <= --_calls_ && a_2()),
            0: --b + (c = 1 + c, (!0) ** (0 <= "undefined" >>> {}) ? (c = 1 + c, 
            (NaN !== ("c" ^ [])) >>> (c += 1, NaN)) : (c = 1 + c, "a" >>> 24..toString() >> (NaN != Number(0xdeadn << 16n | 0xbeefn)) <= (8 ^ (24..toString(), 
            "bar")))),
            in: (c = 1 + c, !1 | 0 == (5 ^ []) ? (c = 1 + c, 5 + -1 % 24..toString() ^ 0) : (c = 1 + c, 
            (a_2 <<= 1) <= (1 <= (a_2 = NaN))))
        } ? (c += 1) + b : function(a_2) {}, "object", {
            a_2: a_2,
            static: {
                in: (c = 1 + c, 24..toString(), !1 / ("number" | this))
            }[a++ + (a_2 && "function" == typeof a_2.c && 0 <= --_calls_ && (c = 1 + c, 
            c += 1, a_2.c)(""))],
            "": "function" == typeof f1 && 0 <= --_calls_ && f1(),
            c: a_2 && "function" == typeof a_2.undefined && 0 <= --_calls_ && a_2.undefined`${c = 1 + c, 
            c += 1, !0 !== (a_2 && ({
                then: a_2[c = 1 + c, c += 1, a_2 && (a_2.next += 1 / 0)]
            } = {
                then: {}
            }))}
${c = 1 + c, c += 1, a_2 && (a_2.in = !0)}
${c = 1 + c, NaN ^ void 0 << 24..toString() || (a_2 += ("" != 24..toString()) % !0)}
${c = 1 + c, c += 1, 25 != (null >>> 38..toString() | [] < "undefined")}`,
            next: a++ + a
        }[/[abc4]/g.exec(((c += 1) + (b = a) || b || 5).toString())]),
        ...--b + (b-- || 5).toString()[--b + (a_2 && a_2.b)],
        b: a++ + delete b
    }) && 0 < --brake2);
} catch (a_2) {
    a = function(arguments_1) {
        var brake21 = 5;
        do {
            c = 1 + (c = 1 + c), 24..toString(), Number(0xdeadn << 16n | 0xbeefn), 
            c = 1 + c, arguments_1 && (arguments_1.foo = 2 < [] ^ 22), c = (c = 1 + c) + 1 + 1;
        } while (a++ + ++a && 0 < --brake21);
        c += 1;
    }(a_2, b--);
}

console.log(null, a, b, c, 1 / 0, NaN, void 0);

original result:
null 165 -10 345 Infinity NaN undefined

uglified result:
null 125 -10 155 Infinity NaN undefined

// reduced test case (output will differ)

// (beautified)
(function f0(await_1) {
    async function f1() {
        await_1 /= 0 in (await_1 = console.log());
    }
    f1();
    await_1[0];
})("b");
// output: TypeError: Cannot read property '0' of undefined
// minify: 
// 
// options: {
//   "mangle": false,
//   "output": {
//     "v8": true
//   },
//   "validate": true
// }

minify(options):
{
  "mangle": false,
  "output": {
    "v8": true
  }
}

Suspicious compress options:
  dead_code