ufuzz failure

[alexlamsl]

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

for (var brake1 = 5; a++ + (typeof f0 == "function" && --_calls_ >= 0 && f0()) && brake1 > 0; --brake1) {
    switch (typeof f0 == "function" && --_calls_ >= 0 && f0(a--, ..."" + a, "")) {
      case --b + +a:
        a++ + (0 === 1 ? a : b);
        if (a++ + (a && typeof a.get == "function" && --_calls_ >= 0 && a.get())) {
            try {
                c = c + 1;
            } catch (await) {} finally {
                c = c + 1;
                L38962: {
                    {
                        var brake10 = 5;
                        do {
                            (c = c + 1) + (typeof f0 == "function" && --_calls_ >= 0 && f0((c = 1 + c, 
                            undefined >= 38..toString() <= (-1 === "undefined") >= (false % 0 ^ 5 >>> undefined))));
                        } while ({
                            __proto__: (c = 1 + c, (3 | [ , 0 ].length === 2) / (a %= -1 % []) || "foo" >> 4 !== (2 || "a")) || {}
                        }[[ (c = 1 + c, [ , 0 ][1] + 0 - (null === -4) != (a && (a.foo = 24..toString() & 24..toString() | (/[a2][^e]+$/ && "foo")))) ][c = 1 + c, 
                        ((NaN == "undefined") + (a && (a[c = 1 + c, -3 / "b" * (-0 + 2) ^ +delete "bar"] = "a" || false))) ** ((this | "bar") === "" >> /[a2][^e]+$/)]] && --brake10 > 0);
                    }
                    c = c + 1;
                    {
                        var undefined_1 = function NaN(foo_2, undefined_1) {}((c = 1 + c, 
                        undefined_1 && (undefined_1[a++ + b--] = (c = c + 1, -5 - -0) && -0 - false === (-4 != 38..toString()))));
                    }
                    {
                        var brake14 = 5;
                        L38963: do {
                            {
                                var brake15 = 5;
                                while (--b + (typeof f1 == "function" && --_calls_ >= 0 && f1`${c = 1 + c, 
                                (undefined >> "function" ^ Infinity > 24..toString()) % ([] / ([ , 0 ].length === 2) ^ Infinity != 2)}} `) && --brake15 > 0) {
                                    var brake16 = 5;
                                    while ((c = 1 + c, (-2 == "number" == (undefined_1 += -4 % ([ , 0 ].length === 2))) << (true - "", 
                                    c = c + 1, false)) && --brake16 > 0) {
                                        c = 1 + c, undefined / "number" & (-3) ** -3, 
                                        undefined_1 && (undefined_1[--b + (c = 1 + c, 
                                        (undefined_1 && ({
                                            value: undefined_1.get
                                        } = {
                                            value: "" - /[a2][^e]+$/
                                        })) >>> ("undefined" && [ , 0 ][1]) > ((c = c + 1, 
                                        /[a2][^e]+$/) <= ("b" && "number")))] += (undefined_1 && (undefined_1.undefined = [] >= 2)) > (true >= -2));
                                    }
                                }
                            }
                        } while ((c = c + 1) + (typeof undefined_1 == "function" && --_calls_ >= 0 && undefined_1((c = 1 + c, 
                        true / 23..toString() >>> (-3 || undefined) > void (5 % false)), (c = 1 + c, 
                        (undefined_1 && (undefined_1[((c = 1 + c, ("function" + "b" < (0 || [ , 0 ][1])) / (-5 > -4 === -0 % 38..toString())) || a || 3).toString()] -= 5 % 23..toString() <= (24..toString() == null))) !== (38..toString() > ([ , 0 ].length === 2)) >> (undefined_1 && (undefined_1.undefined <<= -5 ^ 5))), (c = 1 + c, 
                        undefined_1 && (undefined_1.get += (("object" ^ 5) & "a" >= 3) == ([ , 0 ][1] < 22 != 24..toString() >> /[a2][^e]+$/))))) && --brake14 > 0);
                    }
                    try {
                        try {
                        } catch (bar_2) {
                            c = 1 + c, (c = c + 1, 4 == 25) << (undefined_1 && ({
                                done: undefined_1.NaN
                            } = {
                                done: (-5 - "c") ** (bar_2 && (bar_2.null += "b" > false))
                            }));
                            c = 1 + c, (-3 >>> -5 && this / 1) !== (c = c + 1, -3 << true);
                        } finally {
                            c = 1 + c, (-4 << this > 38..toString() >> []) >> ((2, 
                            "object") > ("function" ^ 0));
                            c = 1 + c, ((undefined_1 && (undefined_1[c = 1 + c, 
                            (null | [ , 0 ].length === 2) & (undefined_1 -= 25 ^ [ , 0 ][1]) ^ (-0 || 25) >> ([ , 0 ][1] ^ 5)] = 2 % ([ 3n ][0] > 2))) ^ {} + 5) + ("c" >= "c" <= ("" !== "bar"));
                            c = 1 + c, (undefined_1 && (undefined_1[typeof f1 == "function" && --_calls_ >= 0 && f1((c = 1 + c, 
                            ("b" !== -2) <= delete "foo" ^ (("number" || Infinity) ^ (undefined_1 && ({
                                var: undefined_1.get
                            } = {
                                var: /[a2][^e]+$/ << -4
                            })))))] |= undefined == 0 | (undefined_1 && (undefined_1[c = 1 + c, 
                            [ , 0 ][1] > "object" !== true % "" ^ {} >> "" !== (undefined_1 && (undefined_1[c = 1 + c, 
                            (-0 ^ null) + (undefined_1 && (undefined_1.b = -2 | this)), 
                            false - undefined <= ("number" === "b")] = undefined != "foo"))] *= "" == "function")))) >>> ((-3 & -5) !== 25 >= 23..toString());
                            c = 1 + c, ((-4 && "undefined") <= -1 % "") >>> (/[a2][^e]+$/ * "c" == ([ , 0 ][1] === 3));
                        }
                    } finally {
                        for (var brake27 = 5; (c = 1 + c, (undefined_1 && (undefined_1.set += "bar" > NaN)) * ("object" + "c"), 
                        (undefined_1 && (undefined_1.in = 2 - true)) >> + -1) && brake27 > 0; --brake27) {
                            c = 1 + c, (25 && "a") - (undefined_1 && (undefined_1.a += 2 <= Infinity)) ^ 5 >= 4 >= (25 > -4);
                        }
                        var arguments = (c = 1 + c, 24..toString() + "number" ^ 5 >= null || (undefined_1 && (undefined_1[c = 1 + c, 
                        undefined_1 && (undefined_1[1 === 1 ? a : b] = (-4 % -1 != (25 != [])) - (("a" > -3) + (undefined_1 += [ 3n ][0] > 2 !== 1)))] *= 2 > Infinity)) < ("c" === ""));
                    }
                }
            }
        } else {
            var expr30 = (c = c + 1) + (typeof f1 == "function" && --_calls_ >= 0 && f1(-2));
            for (var key30 in expr30) {
                c = 1 + c;
                var async_1 = expr30[key30];
                L38964: for (var brake31 = 5; {
                    static: 1 === 1 ? a : b,
                    get: typeof f1 == "function" && --_calls_ >= 0 && f1(...[ ..."" + key30, (c = 1 + c, 
                    ((-5 | 25) !== this >>> 3) < ("undefined" >>> 4 && !22)) ]),
                    "\t": --b + (c = c + 1, [ , 0 ][1] / "function" + ("bar" <= 22))
                } && brake31 > 0; --brake31) {
                    var expr32 = a++ + void function undefined() {
                        {
                            var undefined_1 = function undefined(undefined_1, arguments) {
                            }(true, (c = 1 + c, ((-4 ^ /[a2][^e]+$/) <= ({} < "c")) / (22 <= 23..toString() >= [] * "bar")));
                        }
                    }();
                    for (let key32 in expr32) {
                        c = 1 + c;
                        var b_2 = expr32[key32];
                        var arguments_1 = +((b_2 && (b_2.Infinity = (async_1 && ([ async_1[c = 1 + c, 
                        (void 0 ^ null - 2) > ((5, Infinity) & (NaN | "foo"))] ] = [ "number" >> {} ])) == "a" / 0)) % (-0 || this || NaN ^ undefined));
                    }
                }
            }
        }
        {
            var brake35 = 5;
            while ((c = c + 1) + {
                c: void (a && (a.next *= (2 - -1) ** (23..toString() === -2) == (void "object" ^ NaN != false))),
                1.5: (c = c + 1) + (b |= a),
                a: a,
                [({
                    a: a
                }.set || 6).toString()[(c = c + 1) + typeof void a]]: {
                    "": --b
                },
                NaN: a && a[--b + ~(((a && (a.static = 24..toString() || [ , 0 ].length === 2)) + (-4 >>> NaN)) % ([ , 0 ].length === 2 === "c" & 25 >> undefined))]
            }[(c = c + 1) + (typeof (true in [ a++ + (-5 in [ (c = 1 + c, ((a && (a.in += /[a2][^e]+$/ && 22)) != (this | NaN)) - (/[a2][^e]+$/ ^ {} ^ (a = 0 > "a"))) ]), [ (c = 1 + c, 
            (2 > [ , 0 ][1] != null / 25) >= !(1 / "")) ].c ]) || 9).toString()[(c = c + 1) + (b = a)]] && --brake35 > 0) {
                if ({}) {
                    c = c + 1;
                }
            }
        }
        break;

      case --b + 4:
        break;

      default:
        ;

      case a++ + this:
        break;
    }
}

if (0 === 1 ? a : b) {
    var expr40 = --b + typeof (a++ + (23..toString() - 23..toString() == this / "function", 
    (5, 5) >> (c = c + 1, 25)));
    for (var key40 in expr40) {
        continue;
    }
} else if (a++ + /[abc4]/g.exec(((c = c + 1) + (a && a[--b + a--]) || b || 5).toString())) {
    var b;
    b && b[/[abc4]/g.exec((a++ + new function foo(undefined, yield, async_2) {
        this[--b + [][a++ + [ (c = 1 + c, (undefined && (undefined[(c = c + 1) + ~((yield /= (this, 
        1)) * (NaN <= "bar") && (22, -1) == (async_2 && (async_2[c = 1 + c, ~-1 >> 38..toString() + [] >>> ([ , 0 ][1] - "bar" == (5 === undefined))] = "foo" !== 1)))] = !"object" + [ , 0 ][1] % null)) % (async_2 && (async_2.var += "function" ^ 2 || -0 + {}))), (c = 1 + c, 
        -(/[a2][^e]+$/ % 4 == (c = c + 1, "function"))), (c = 1 + c, ("c" & {}) + (23..toString() < 24..toString()) || ("undefined" < "c") % ("undefined" >= -4)) ].b]] /= (("a" ^ "function") & "bar" + 23..toString(), 
        ("number" ^ 38..toString()) !== ("c" | "object")) * ((-5 === null, 24..toString() ^ 4) + (yield = (false && "undefined") != null / "number"));
    }("c") || b || 5).toString())];
}

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

// uglified code
// (beautified)
for (var n, t, f, e, o, i, a, r, c, l, u, y, g, d, h = 10, s = 100, N = 10, p = 0, v = 5; s++ + ("function" == typeof f0 && 0 <= --h && f0()) && 0 < v; --v) {
    switch ("function" == typeof f0 && 0 <= --h && f0(s--, ..."" + s, "")) {
      case --N + +s:
        if (s++, s++ + (s && "function" == typeof s.get && 0 <= --h && s.get())) {
            try {
                p += 1;
            } catch (n) {} finally {
                for (p += 1, n = 5; p += 1, "function" == typeof f0 && 0 <= --h && f0((p = 1 + p, 
                !1)), {
                    __proto__: (p = 1 + p, (3 | 2 === [ , 0 ].length) / (s %= NaN) || !0)
                }[[ (p = 1 + p, 0 != (s && (s.foo = 24))) ][p = 1 + p, (!1 + (s && (s[p = 1 + p, 
                1] = "a"))) ** (0 == ("bar" | this))]] && 0 < --n; ) {}
                p = 1 + (p + 1), t = void (t && (t[s++ + N--] = (p += 1, !1))), 
                f = 5;
                do {
                    for (e = 5; --N + ("function" == typeof f1 && 0 <= --h && f1`${p = 1 + p, 
                    1 % ([] / (2 === [ , 0 ].length) ^ !0)}} `) && 0 < --e; ) {
                        for (o = 5; p = 1 + p, (0 == (t += -4 % (2 === [ , 0 ].length))) << (p += 1, 
                        !1) && 0 < --o; ) {
                            p = 1 + p, t && (t[--N + (p = 1 + p, (t && ({
                                value: t.get
                            } = {
                                value: NaN
                            })) >>> 0 > (p += 1, !0))] += !0 < (t && (t.undefined = !1)));
                        }
                    }
                } while ((p += 1) + ("function" == typeof t && 0 <= --h && t(!1, (p = 1 + (1 + p), 
                (t && (t[p = 1 + p, (s || 3).toString()] -= !1)) !== ((2 === [ , 0 ].length) < "38") >> (t && (t.undefined <<= -2))), (p = 1 + p, 
                t && (t.get += !1)))) && 0 < --f);
                try {
                    p = 1 + (p = 1 + p), t && (t[p = 1 + p, (null | 2 === [ , 0 ].length) & (t -= 25) ^ 0] = 2 % (2 < 3n)), 
                    p = 1 + p, t && (t["function" == typeof f1 && 0 <= --h && f1((p = 1 + p, 
                    "number" ^ (t && ({
                        var: t.get
                    } = {
                        var: 0
                    })) ^ !0))] |= !1 | (t && (t[p = 1 + p, !0 ^ 0 !== (t && (t[p = 1 + p, 
                    t && (t.b = -2 | this), !1] = !0))] *= !1))), p = 1 + p;
                } finally {
                    for (i = 5; p = 1 + p, t && (t.set += !1), (t && (t.in = 1)) >> -1 && 0 < i; --i) {
                        p = 1 + p, t && (t.a += !0);
                    }
                    p = 1 + p;
                }
            }
        } else {
            for (r in a = (p += 1) + ("function" == typeof f1 && 0 <= --h && f1(-2))) {
                for (p = 1 + p, c = a[r], l = 5; "function" == typeof f1 && 0 <= --h && f1(..."" + r, (p = 1 + p, 
                (-5 != this >>> 3) < 0)), --N, p += 1, 0 < l; --l) {
                    for (d in u = s++ + void function undefined() {
                        p = 1 + p;
                    }()) {
                        p = 1 + p, (y = u[d]) && (y.Infinity = NaN == (c && ([ c[p = 1 + p, 
                        !1] ] = [ 0 ])));
                    }
                }
            }
        }
        for (g = 5; (p += 1) + {
            c: void (s && (s.next *= !0)),
            1.5: (p += 1) + (N |= s),
            a: s,
            [({
                a: s
            }.set || 6).toString()[(p += 1) + "undefined"]]: {
                "": --N
            },
            NaN: s && s[--N + ~(((s && (s.static = "24")) + (-4 >>> NaN)) % (2 === [ , 0 ].length === "c" & 25))]
        }[(p += 1) + ("" + (typeof (!0 in [ s++ + (-5 in [ (p = 1 + p, ((s && (s.in += 22)) != (NaN | this)) - (0 ^ (s = !1))) ]), [ (p = 1 + p, 
        !0) ].c ]) || 9))[(p += 1) + (N = s)]] && 0 < --g; ) {
            p += 1;
        }
        break;

      case 4 + --N:
        break;

      default:
      case s++ + this:
    }
}

N ? (--N, s++, p += 1) : ((p += 1) + (++s && s[--N + s--]) || N || 5).toString(), 
console.log(null, s, N, p, Infinity, NaN, void 0);

original result:
null 113 -2 6 Infinity NaN undefined

uglified result:
null 111 -1 1 Infinity NaN undefined

// reduced test case (output will differ)

// (beautified)
var b = 10;

for (var brake1 = 5; brake1; --brake1) {
    switch (0) {
      case --b:
      case --b:
    }
}

if (b) {} else if ((--b).toString) {
    b && async_2;
}
// output: ReferenceError: async_2 is not defined
// minify: 
// options: {
//   "compress": {
//     "hoist_vars": true,
//     "keep_infinity": true,
//     "passes": 1000000,
//     "unsafe": true
//   },
//   "keep_fargs": true,
//   "keep_fnames": true,
//   "toplevel": 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,
  "output": {
    "v8": true
  }
}

Suspicious compress options:
  booleans
  conditionals
  evaluate
  passes