diff --git a/lib/compress.js b/lib/compress.js
index 9d6eb098..b07ac261 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -346,7 +346,7 @@ merge(Compressor.prototype, {
                     if (ref.scope.uses_eval || ref.scope.uses_with) break;
 
                     // Constant single use vars can be replaced in any scope.
-                    if (var_decl.value.is_constant(compressor)) {
+                    if (!(var_decl.value instanceof AST_RegExp) && var_decl.value.is_constant(compressor)) {
                         var ctt = new TreeTransformer(function(node) {
                             if (node === ref)
                                 return replace_var(node, ctt.parent(), true);
diff --git a/lib/output.js b/lib/output.js
index 5de1596d..a26bd06b 100644
--- a/lib/output.js
+++ b/lib/output.js
@@ -520,7 +520,8 @@ function OutputStream(options) {
 
     PARENS([ AST_Unary, AST_Undefined ], function(output){
         var p = output.parent();
-        return p instanceof AST_PropAccess && p.expression === this;
+        return p instanceof AST_PropAccess && p.expression === this
+            || p instanceof AST_New;
     });
 
     PARENS(AST_Seq, function(output){
@@ -1531,7 +1532,12 @@ function OutputStream(options) {
 
     // self should be AST_New.  decide if we want to show parens or not.
     function no_constructor_parens(self, output) {
-        return self.args.length == 0 && !output.option("beautify");
+        return self.args.length == 0 && !output.option("beautify") ||
+            !(self.expression instanceof AST_SymbolRef ||
+              self.expression instanceof AST_Call ||
+              self.expression instanceof AST_Function ||
+              self.expression instanceof AST_Assign
+            );
     };
 
     function best_of(a) {
diff --git a/lib/parse.js b/lib/parse.js
index b776ec12..14da6b01 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -501,6 +501,8 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
             break;
         } else if (ch == "\\") {
             prev_backslash = true;
+        } else if ("\r\n\u2028\u2029".indexOf(ch) >= 0) {
+            parse_error("Unexpected line terminator");
         } else {
             regexp += ch;
         }
diff --git a/test/compress/collapse_vars.js b/test/compress/collapse_vars.js
index 934a5c73..ef7af9ed 100644
--- a/test/compress/collapse_vars.js
+++ b/test/compress/collapse_vars.js
@@ -1153,3 +1153,59 @@ collapse_vars_short_circuited_conditions: {
     }
 }
 
+collapse_vars_regexp: {
+    options = {
+        collapse_vars: true,
+        loops:         false,
+        sequences:     true,
+        dead_code:     true,
+        conditionals:  true,
+        comparisons:   true,
+        evaluate:      true,
+        booleans:      true,
+        unused:        true,
+        hoist_funs:    true,
+        keep_fargs:    true,
+        if_return:     true,
+        join_vars:     true,
+        cascade:       true,
+        side_effects:  true,
+    }
+    input: {
+        function f1() {
+            var k = 9;
+            var rx = /[A-Z]+/;
+            return [rx, k];
+        }
+        function f2() {
+            var rx = /[abc123]+/;
+            return function(s) {
+                return rx.exec(s);
+            };
+        }
+        (function(){
+            var result;
+            var s = 'acdabcdeabbb';
+            var rx = /ab*/g;
+            while (result = rx.exec(s)) {
+                console.log(result[0]);
+            }
+        })();
+    }
+    expect: {
+        function f1() {
+            return [/[A-Z]+/, 9];
+        }
+        function f2() {
+            var rx = /[abc123]+/;
+            return function(s) {
+                return rx.exec(s);
+            };
+        }
+        (function(){
+            var result, rx = /ab*/g;
+            while (result = rx.exec('acdabcdeabbb'))
+                console.log(result[0]);
+        })();
+    }
+}
diff --git a/test/compress/new.js b/test/compress/new.js
index 4b2c51c3..d956ae27 100644
--- a/test/compress/new.js
+++ b/test/compress/new.js
@@ -10,3 +10,11 @@ new_statement: {
     }
     expect_exact: "new x(1);new x(1)(2);new x(1)(2)(3);new new x(1);new new x(1)(2);new new x(1)(2);(new new x(1))(2);"
 }
+
+new_with_rewritten_true_value: {
+    options = { booleans: true }
+    input: {
+        new true;
+    }
+    expect_exact: "new(!0);"
+}
diff --git a/test/mocha/line-endings.js b/test/mocha/line-endings.js
index 8fd56a19..3457dd70 100644
--- a/test/mocha/line-endings.js
+++ b/test/mocha/line-endings.js
@@ -30,5 +30,27 @@ describe("line-endings", function() {
         var result = Uglify.minify(js, options);
         assert.strictEqual(result.code, expected_code);
     });
+
+    it("Should not allow line terminators in regexp", function() {
+        var inputs = [
+            "/\n/",
+            "/\r/",
+            "/\u2028/",
+            "/\u2029/",
+            "/someRandomTextLike[]()*AndThen\n/"
+        ]
+        var test = function(input) {
+            return function() {
+                Uglify.parse(input);
+            }
+        }
+        var fail = function(e) {
+            return e instanceof Uglify.JS_Parse_Error &&
+                e.message === "Unexpected line terminator";
+        }
+        for (var i = 0; i < inputs.length; i++) {
+            assert.throws(test(inputs[i]), fail);
+        }
+    });
 });
 
diff --git a/test/mocha/new.js b/test/mocha/new.js
new file mode 100644
index 00000000..7e7aea7d
--- /dev/null
+++ b/test/mocha/new.js
@@ -0,0 +1,34 @@
+var assert = require("assert");
+var uglify = require("../../");
+
+describe("New", function() {
+    it("Should attach callback parens after some tokens", function() {
+        var tests = [
+            "new x(1);",
+            "new (function(foo){this.foo=foo;})(1);",
+            "new true;",
+            "new (0);",
+            "new (!0);",
+            "new (bar = function(foo) {this.foo=foo;})(123);"
+        ];
+        var expected = [
+            "new x(1);",
+            "new function(foo) {\n    this.foo = foo;\n}(1);",
+            "new true;",
+            "new 0;",
+            "new (!0);",
+            "new (bar = function(foo) {\n    this.foo = foo;\n})(123);"
+        ];
+        for (var i = 0; i < tests.length; i++) {
+            assert.strictEqual(
+                uglify.minify(tests[i], {
+                    fromString: true,
+                    output: {beautify: true},
+                    compress: false,
+                    mangle: false
+                }).code,
+                expected[i]
+            );
+        }
+    });
+});
\ No newline at end of file
diff --git a/test/run-tests.js b/test/run-tests.js
index b6677475..1c98a1ae 100755
--- a/test/run-tests.js
+++ b/test/run-tests.js
@@ -163,9 +163,16 @@ function run_compress_tests() {
 
 function parse_test(file) {
     var script = fs.readFileSync(file, "utf8");
-    var ast = U.parse(script, {
-        filename: file
-    });
+    // TODO try/catch can be removed after fixing https://github.com/mishoo/UglifyJS2/issues/348
+    try {
+        var ast = U.parse(script, {
+            filename: file
+        });
+    } catch (e) {
+        console.log("Caught error while parsing tests in " + file + "\n");
+        console.log(e);
+        throw e;
+    }
     var tests = {};
     var tw = new U.TreeWalker(function(node, descend){
         if (node instanceof U.AST_LabeledStatement
diff --git a/tools/exports.js b/tools/exports.js
index 110b5c4e..09acc13e 100644
--- a/tools/exports.js
+++ b/tools/exports.js
@@ -14,5 +14,6 @@ exports["merge"] = merge;
 exports["parse"] = parse;
 exports["push_uniq"] = push_uniq;
 exports["string_template"] = string_template;
+exports["tokenizer"] = tokenizer;
 exports["is_identifier"] = is_identifier;
 exports["SymbolDef"] = SymbolDef;