ufuzz failure

[alexlamsl]

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

function f0(foo_2, a_1, foo_2) {
    function f1() {
        function f2({
            c: bar,
            foo: b_2,
            null: arguments
        }, arguments_2 = 1) {
            function f3(Infinity) {
            }
            var Infinity_2 = f3(NaN, 4, (c = 1 + c, b_2 && (b_2.b = (3 && 0) <= ("foo" !== undefined) ^ (4 ^ "") >> (/[a2][^e]+$/ ^ "object"))));
        }
        var a = f2({
            foo: 0 === 1 ? a : b,
            1.5: 1
        });
        function f4([], a_2) {
            {
                var expr1 = (c = 1 + c, ("function" & {} ^ (a_1 && (a_1.then = 3 && "bar"))) * (("b" || -3) & (this && -4)));
                for (var key1 in expr1) {
                    c = 1 + c, (c = c + 1, "undefined" == -1) - (key1 += (a_1 && (a_1[c = 1 + c, foo_2 = (-1 != true === (null === "bar"), 
                    a = 4 % "number" >= 38..toString() >> -2)] = 0 > "function")) | -1 % 25);
                }
            }
            {
                var expr3 = (c = 1 + c, c = c + 1, (c = c + 1, 1) + ({} + 25));
                for (var key3 in expr3) {
                    c = 1 + c, ("bar", -0) >>> ("object" != Infinity) != (NaN == "function" || 5 * -1);
                }
            }
        }
        var NaN = f4([ --b + ((c = 1 + c, c = c + 1, "a" / 5 >> (/[a2][^e]+$/ & true)) || 9).toString()[c = 1 + c, 
        (c = c + 1, "a" ^ "function") >> (a_1 = false / "undefined" * (null === "bar"))], this, a++ + +function bar_2() {
        }() ], a++ + a, -3);
        function f5(a_1, a_2, a_2) {
            c = 1 + c, (foo_2 += -4 != 24..toString()) % ([] === "undefined") === (true != 22) <= (a_2 && (a_2[c = 1 + c, 
            (([ , 0 ][1], "a") ^ ([ , 0 ][1] ^ 25)) & (4, "object", NaN && (NaN[c = 1 + c, 24..toString() * /[a2][^e]+$/ >> ("foo" !== -5) != ([] ^ -4) < ("c" >= 25)] = 0 >>> /[a2][^e]+$/))] /= (-5, 
            /[a2][^e]+$/)));
            c = c + 1;
        }
        var NaN_2 = f5(0 === 1 ? a : b);
        function f6(bar) {
            try {
                c = 1 + c, ((23..toString() ^ 23..toString()) >> ("c" << NaN)) / (NaN_2 && ({
                    "\t": NaN_2.null
                } = {
                    "\t": (Infinity === [ , 0 ][1]) / ([] << 23..toString())
                }));
            } catch (a_2) {
            } finally {
            }
            {
                var brake9 = 5;
                L13367: while ((c = 1 + c, -1 * false > (bar && ({
                    async: bar.null
                } = {
                    async: "function" << false
                })) && (null || -3) * (-4 % -1)) && --brake9 > 0) {
                    c = 1 + c, ((NaN = 22 ^ "") >= (foo_2 && (foo_2.next = 23..toString() % 0))) / (24..toString() > "" == (a = Infinity >= "number"));
                }
            }
        }
        var a_2 = f6({
            get: (c = 1 + c, (foo_2 && (foo_2[c = 1 + c, ((false !== 22) + ("b" & -0)) % ((c = c + 1, 
            3) * (1 >= "undefined"))] >>>= 4 === 3), 24..toString() & [ , 0 ][1]) ^ ([] | "function" || -5 != NaN))
        }, this);
        function f7(b, a_2) {
            function f8(foo_2_2) {
            }
            var b = f8();
            function f9(b_2, NaN_2, a_1) {
            }
            var a_1 = f9();
            function f10(b_2, a_1, foo) {
            }
            var bar = f10("b", (c = 1 + c, ("" ^ [ , 0 ][1] | "b" >> 22) >= ((-3 ^ 0) != (-1 ^ 25))), -5);
        }
        var foo_2_1 = f7();
    }
    var a = f1(undefined, "function", foo_2 /= b + 1 - .1 - .1 - .1);
}

var bar_1 = f0(1);

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

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

function f0(foo_2, a_1, foo_2) {
    !function() {
        var b_2;
        c = 1 + c, b && (b_2.b = 5);
        var NaN = function() {
            var key1, key3;
            for (key1 in c = 1 + c, ("function" & {} ^ (a_1 && (a_1.then = "bar"))) * ("b" & (this && -4))) {
                c = 1 + c, c += 1, key1 += -1 | (a_1 && (a_1[c = 1 + c, foo_2 = 0 / 0 >= 38..toString() >> -2] = !1));
            }
            for (key3 in c = 1 + c, c += 1, c += 1, 1 + ({} + 25)) {
                c = 1 + c;
            }
        }((--b, c = 1 + c, c += 1, 9..toString()[c = 1 + c, c += 1, 0 >> (a_1 = 0 / 0)])), NaN_2 = function(a_2, a_2) {
            c = 1 + c, foo_2 += -4 != 24..toString(), a_2 && (a_2[c = 1 + c, 25 & (NaN && (NaN[c = 1 + c, 
            24..toString() * /[a2][^e]+$/ >> !0 != (-4 ^ []) < !1] = 0))] /= /[a2][^e]+$/), 
            c += 1;
        }();
        !function(bar) {
            try {
                c = 1 + c, 23..toString(), 23..toString(), NaN_2 && ({
                    "\t": NaN_2.null
                } = {
                    "\t": !1 / ([] << 23..toString())
                });
            } catch (a_2) {}
            c = 1 + c, bar && ({
                async: bar.null
            } = {
                async: 0
            });
        }({
            get: (c = 1 + c, foo_2 && (foo_2[c = 1 + c, 1 % (!1 * (c += 1, 3))] >>>= !1), 0 & 24..toString() ^ ("function" | [] || -5 != NaN))
        }), c = 1 + c;
    }(foo_2 /= b + 1 - .1 - .1 - .1);
}

var bar_1 = f0(1);

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

original result:
null 100 9 33 Infinity NaN undefined

uglified result:
evalmachine.<anonymous>:1
var _calls_=10,a=100,b=10,c=0;function f0(foo_2,a_1,foo_2){!function(){var b_2;c=1+c,b&&(b_2.b=5);var NaN=function(){var key1,key3;for(key1 in c=1+c,("function"&{}^(a_1&&(a_1.then="bar")))*("b"&(this&&-4)))c=1+c,c+=1,key1+=-1|(a_1&&(a_1[c=1+c,foo_2=0/0>=38..toString()>>-2]=!1));for(key3 in c=1+c,c+=1,c+=1,1+({}+25))c=1+c}((--b,c=1+c,c+=1,9..toString()[c=1+c,c+=1,0>>(a_1=0/0)])),NaN_2=function(a_2,a_2){c=1+c,foo_2+=-4!=24..toString(),a_2&&(a_2[c=1+c,25&(NaN&&(NaN[c=1+c,24..toString()*/[a2][^e]+$/>>!0!=(-4^[])<!1]=0))]/=/[a2][^e]+$/),c+=1}();!function(bar){try{c=1+c,23..toString(),23..toString(),NaN_2&&({"\t":NaN_2.null}={"\t":!1/([]<<23..toString())})}catch(a_2){}c=1+c,bar&&({async:bar.null}={async:0})}({get:(c=1+c,foo_2&&(foo_2[c=1+c,1%(!1*(c+=1,3))]>>>=!1),0&24..toString()^("function"|[]||-5!=NaN))}),c=1+c}(foo_2/=b+1-.1-.1-.1)}var bar_1=f0(1);console.log(null,a,b,c,1/0,NaN,void 0);
                                                                                              ^

TypeError: Cannot set property 'b' of undefined
    at evalmachine.<anonymous>:1:95
    at f0 (evalmachine.<anonymous>:1:820)
    at evalmachine.<anonymous>:1:852
    at ContextifyScript.Script.runInContext (vm.js:59:29)
    at Object.runInContext (vm.js:120:6)
    at run_code_vm (D:\a\UglifyJS\UglifyJS\test\sandbox.js:257:12)
    at Object.exports.run_code (D:\a\UglifyJS\UglifyJS\test\sandbox.js:37:16)
    at run_code (D:\a\UglifyJS\UglifyJS\test\ufuzz\index.js:2082:20)
    at D:\a\UglifyJS\UglifyJS\test\ufuzz\index.js:2482:29
    at Array.forEach (<anonymous>)

// reduced test case (output will differ)

// (beautified)
var b = 1;

function f0() {
    function f1() {
        function f2({
            foo: b_2
        }) {
            b_2 && b_2.b;
        }
        f2({
            foo: b
        });
    }
    f1();
}

f0();
// output: 
// minify: TypeError: Cannot read property 'b' of undefined
// options: {
//   "mangle": false,
//   "output": {
//     "v8": true
//   },
//   "validate": true
// }

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

Suspicious compress options:
  collapse_vars
  conditionals
  evaluate
  inline
  keep_fargs
  properties
  reduce_vars
  side_effects
  unused