Most likely V8 specific issue

[alexlamsl]

No --compress or --mangle is required to trigger this one:

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

for (var brake1 = 5; (c = c + 1) + (c = c + 1, 1 < []) >> NaN | "function" && 2 ^ Infinity && brake1 > 0; --brake1) {
    var brake2 = 5;
    do {
        {
            var brake3 = 5;
            while (/[abc4]/.test(("function" || b || 5).toString()) && --brake3 > 0) {
                for (var brake4 = 5; a-- && brake4 > 0; --brake4) {
                    switch (!function Object_6() {
                    }()) {
                      default:
                        a++ + (b |= a);
                        {
                            var brake9 = 5;
                            while ((c = c + 1) + /[abc4]/.test((--b || b || 5).toString()) && --brake9 > 0) {
                                var brake10 = 5;
                                do {
                                    var b_12 = --b + ("undefined" || a || 3).toString(), decodeURIComponent = /[abc4]/.test((--b + typeof (c = 1 + c,
                                    false !== -4 ^ "object" | 2 * -1 ^ [] >> (c = c + 1, 4)) || b || 5).toString());
                                } while ((a++ + 2 - /[a2][^e]+$/ ^ -3 >> "function" === -0 || 22 & "foo", "bar") && --brake10 > 0);
                            }
                        }

                      case -4 / 23..toString() << "undefined" >>> undefined > {} >= false << "undefined" >> 23..toString() > a++:
                        --b + /[abc4]/.test((a-- || b || 5).toString());
                        break;

                      case a++ + ((a++ + "function" === 0 * -4 & /[a2][^e]+$/ ^ (b_12 -= "undefined" << "undefined") % Infinity < "foo" ? b + 1 - .1 - .1 - .1 : (c = c + 1) + function parseFloat_14() {}()) || a || 3).toString():
                        break;

                      case /[abc4]/.test((a++ + typeof foo_15 === "number" || b || 5).toString()):
                        switch (true) {
                          case a++ + new function() {
                                "function" && 2 | [ , 0 ].length === 2, 4 >>> (b_12 === false <= 0 <= "function" & -2);
                                return Math;
                            }():
                            break;

                          case /[abc4]/.test((--b + a-- || b || 5).toString()):
                            break;

                          case 1 === 1 ? a : b:
                            break;

                          case typeof new function() {
                                return Math;
                            }():
                            a++ + NaN;
                            break;
                        }
                        for (var brake18 = 5; (c = c + 1) + ((/[abc4]/.test((/[abc4]/.test(((c = 1 + c,
                        23..toString() == -3 === (c = c + 1, "function") && [] >> -5 & NaN - ([ , 0 ].length === 2)) || b || 5).toString()) || b || 5).toString()) ? (c = c + 1) + typeof decodeURIComponent_19 : a++ + a--) || a || 3).toString() && brake18 > 0; --brake18) {
                            !function f0(decodeURIComponent_21) {
                                if (c = 1 + c, 25 == ([ , 0 ].length === 2) ^ 23..toString(), true != 25 == [] <= Infinity >>> -4) {
                                    c = 1 + c, {} && [ , 0 ][1] == 25 << -0 & Infinity / "function" % -3 * -0;
                                } else {
                                    c = 1 + c, (c = c + 1, -1) >= 4 / Infinity | (c = c + 1, 25), -0 >> Infinity;
                                }
                                var isNaN = (c = 1 + c, 0 + "number" === Infinity != false >>> [ , 0 ][1] - -2 >> -1 !== false), encodeURI_26 = (c = 1 + c,
                                -4 <= [ , 0 ][1] << (b_12 /= "foo" != -5) == undefined | [] && "object" & []);
                            }(/[abc4]/.test(((--b + (c = 1 + c, 0, "number" * [ , 0 ][1] - 25 + "function" | "undefined" | "foo" >>> false) ? (c = 1 + c,
                            4 - 23..toString() * NaN <= "object" > "foo" + [] ^ 22 != undefined) : (c = 1 + c,
                            0 - 25 ^ 3 + [ , 0 ][1] / 25 | 4 >= "undefined" <= {})) || b || 5).toString()));
                        }
                        break;
                    }
                }
            }
        }
    } while ((a++ + 1 === 1 ? a : b) && --brake2 > 0);
}

var decodeURI = a++ + (/[abc4]/.test(((c = c + 1) + (b %= a) || b || 5).toString()) || a || 3).toString();

console.log(null, a, b, c);


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

for (var brake1 = 5; (c = c + 1) + (c = c + 1, 1 < []) >> NaN | "function" && 2 ^ Infinity && brake1 > 0; --brake1) {
    var brake2 = 5;
    do {
        {
            var brake3 = 5;
            while (/[abc4]/.test(("function" || b || 5).toString()) && --brake3 > 0) {
                for (var brake4 = 5; a-- && brake4 > 0; --brake4) {
                    switch (!function Object_6() {}()) {
                      default:
                        a++ + (b |= a);
                        {
                            var brake9 = 5;
                            while ((c = c + 1) + /[abc4]/.test((--b || b || 5).toString()) && --brake9 > 0) {
                                var brake10 = 5;
                                do {
                                    var b_12 = --b + ("undefined" || a || 3).toString(), decodeURIComponent = /[abc4]/.test((--b + typeof (c = 1 + c,
                                    false !== -4 ^ "object" | 2 * -1 ^ [] >> (c = c + 1, 4)) || b || 5).toString());
                                } while ((a++ + 2 - /[a2][^e]+$/ ^ -3 >> "function" === -0 || 22 & "foo", "bar") && --brake10 > 0);
                            }
                        }

                      case -4 / 23..toString() << "undefined" >>> undefined > {} >= false << "undefined" >> 23..toString() > a++:
                        --b + /[abc4]/.test((a-- || b || 5).toString());
                        break;

                      case a++ + ((a++ + "function" === 0 * -4 & /[a2][^e]+$/ ^ (b_12 -= "undefined" << "undefined") % Infinity < "foo" ? b + 1 - .1 - .1 - .1 : (c = c + 1) + function parseFloat_14() {}()) || a || 3).toString():
                        break;

                      case /[abc4]/.test((a++ + typeof foo_15 === "number" || b || 5).toString()):
                        switch (true) {
                          case a++ + new function() {
                                "function" && 2 | [ , 0 ].length === 2, 4 >>> (b_12 === false <= 0 <= "function" & -2);
                                return Math;
                            }():
                            break;

                          case /[abc4]/.test((--b + a-- || b || 5).toString()):
                            break;

                          case 1 === 1 ? a : b:
                            break;

                          case typeof new function() {
                                return Math;
                            }():
                            a++ + NaN;
                            break;
                        }
                        for (var brake18 = 5; (c = c + 1) + ((/[abc4]/.test((/[abc4]/.test(((c = 1 + c,
                        23..toString() == -3 === (c = c + 1, "function") && [] >> -5 & NaN - ([ , 0 ].length === 2)) || b || 5).toString()) || b || 5).toString()) ? (c = c + 1) + typeof decodeURIComponent_19 : a++ + a--) || a || 3).toString() && brake18 > 0; --brake18) {
                            !function f0(decodeURIComponent_21) {
                                if (c = 1 + c, 25 == ([ , 0 ].length === 2) ^ 23..toString(), true != 25 == [] <= Infinity >>> -4) {
                                    c = 1 + c, {} && [ , 0 ][1] == 25 << -0 & Infinity / "function" % -3 * -0;
                                } else {
                                    c = 1 + c, (c = c + 1, -1) >= 4 / Infinity | (c = c + 1, 25), -0 >> Infinity;
                                }
                                var isNaN = (c = 1 + c, 0 + "number" === Infinity != false >>> [ , 0 ][1] - -2 >> -1 !== false), encodeURI_26 = (c = 1 + c,
                                -4 <= [ , 0 ][1] << (b_12 /= "foo" != -5) == undefined | [] && "object" & []);
                            }(/[abc4]/.test(((--b + (c = 1 + c, 0, "number" * [ , 0 ][1] - 25 + "function" | "undefined" | "foo" >>> false) ? (c = 1 + c,
                            4 - 23..toString() * NaN <= "object" > "foo" + [] ^ 22 != undefined) : (c = 1 + c,
                            0 - 25 ^ 3 + [ , 0 ][1] / 25 | 4 >= "undefined" <= {})) || b || 5).toString()));
                        }
                        break;
                    }
                }
            }
        }
    } while ((a++ + 1 === 1 ? a : b) && --brake2 > 0);
}

var decodeURI = a++ + (/[abc4]/.test(((c = c + 1) + (b %= a) || b || 5).toString()) || a || 3).toString();

console.log(null, a, b, c);


original result:
null 6446 1603 23775

uglified result:
illegal access
minify(options):
{ compress: false,
  mangle: false,
  output: { beautify: true, bracketize: true },
  fromString: true }

Suspicious output options:
  screw_ie8
  semicolons
  shebang

Node.js 0.10 / Chakracore

$ bin/uglifyjs test.js -b | node
null 6446 1603 23775

Node.js 0.12

$ bin/uglifyjs test.js -b | node
[stdin]:73
var decodeURI = a++ + (/[abc4]/.test(((c = c + 1) + (b %= a) || b || 5).toStri
                    ^
illegal access

Node.js 4 / 6

$ bin/uglifyjs test.js -b | node
[stdin]:73
var decodeURI = a++ + (/[abc4]/.test(((c = c + 1) + (b %= a) || b || 5).toString()) || a || 3).toString();
                    ^
illegal access

[kzc]

Oddly, even though it appears to be a Node/V8 parser issue, the uglify -b output will run with node --turbo and its results will agree with non-V8 engines.