diff --git a/bin/uglifyjs b/bin/uglifyjs
index 11c3a01a..310023ee 100755
--- a/bin/uglifyjs
+++ b/bin/uglifyjs
@@ -153,7 +153,7 @@ if (ARGS.r) {
 
 var OUTPUT_OPTIONS = {
     beautify: BEAUTIFY ? true : false,
-    preamble: ARGS.preamble || null,
+    preamble: ARGS.preamble || null
 };
 
 if (ARGS.screw_ie8) {
@@ -234,7 +234,7 @@ var SOURCES_CONTENT = {};
 var SOURCE_MAP = ARGS.source_map ? UglifyJS.SourceMap({
     file: P_RELATIVE ? path.relative(path.dirname(ARGS.source_map), OUTPUT_FILE) : OUTPUT_FILE,
     root: ARGS.source_map_root,
-    orig: ORIG_MAP,
+    orig: ORIG_MAP
 }) : null;
 
 OUTPUT_OPTIONS.source_map = SOURCE_MAP;
@@ -287,7 +287,7 @@ async.eachLimit(files, 1, function (file, cb) {
                         filename     : file,
                         toplevel     : TOPLEVEL,
                         expression   : ARGS.expr,
-                        bare_returns : ARGS.bare_returns,
+                        bare_returns : ARGS.bare_returns
                     });
                 } catch(ex) {
                     if (ex instanceof UglifyJS.JS_Parse_Error) {
diff --git a/lib/ast.js b/lib/ast.js
index 5aa1be30..c4fef5fe 100644
--- a/lib/ast.js
+++ b/lib/ast.js
@@ -113,11 +113,11 @@ AST_Node.warn = function(txt, props) {
 /* -----[ statements ]----- */
 
 var AST_Statement = DEFNODE("Statement", null, {
-    $documentation: "Base class of all statements",
+    $documentation: "Base class of all statements"
 });
 
 var AST_Debugger = DEFNODE("Debugger", null, {
-    $documentation: "Represents a debugger statement",
+    $documentation: "Represents a debugger statement"
 }, AST_Statement);
 
 var AST_Directive = DEFNODE("Directive", "value scope", {
@@ -125,7 +125,7 @@ var AST_Directive = DEFNODE("Directive", "value scope", {
     $propdoc: {
         value: "[string] The value of this directive as a plain string (it's not an AST_String!)",
         scope: "[AST_Scope/S] The scope that this directive affects"
-    },
+    }
 }, AST_Statement);
 
 var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
@@ -162,7 +162,7 @@ var AST_Block = DEFNODE("Block", "body", {
 }, AST_Statement);
 
 var AST_BlockStatement = DEFNODE("BlockStatement", null, {
-    $documentation: "A block statement",
+    $documentation: "A block statement"
 }, AST_Block);
 
 var AST_EmptyStatement = DEFNODE("EmptyStatement", null, {
@@ -286,14 +286,14 @@ var AST_Scope = DEFNODE("Scope", "directives variables functions uses_with uses_
         uses_eval: "[boolean/S] tells whether this scope contains a direct call to the global `eval`",
         parent_scope: "[AST_Scope?/S] link to the parent scope",
         enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
-        cname: "[integer/S] current index for mangling variables (used internally by the mangler)",
-    },
+        cname: "[integer/S] current index for mangling variables (used internally by the mangler)"
+    }
 }, AST_Block);
 
 var AST_Toplevel = DEFNODE("Toplevel", "globals", {
     $documentation: "The toplevel scope",
     $propdoc: {
-        globals: "[Object/S] a map of name -> SymbolDef for all undeclared names",
+        globals: "[Object/S] a map of name -> SymbolDef for all undeclared names"
     },
     wrap_enclose: function(arg_parameter_pairs) {
         var self = this;
@@ -343,11 +343,11 @@ var AST_Toplevel = DEFNODE("Toplevel", "globals", {
                             body: new AST_Assign({
                                 left: new AST_Sub({
                                     expression: new AST_SymbolRef({ name: "exports" }),
-                                    property: new AST_String({ value: sym.name }),
+                                    property: new AST_String({ value: sym.name })
                                 }),
                                 operator: "=",
-                                right: new AST_SymbolRef(sym),
-                            }),
+                                right: new AST_SymbolRef(sym)
+                            })
                         }));
                     });
                     return MAP.splice(body);
@@ -417,7 +417,7 @@ var AST_Throw = DEFNODE("Throw", null, {
 var AST_LoopControl = DEFNODE("LoopControl", "label", {
     $documentation: "Base class for loop control statements (`break` and `continue`)",
     $propdoc: {
-        label: "[AST_LabelRef?] the label, or null if none",
+        label: "[AST_LabelRef?] the label, or null if none"
     },
     _walk: function(visitor) {
         return visitor._visit(this, this.label && function(){
@@ -467,11 +467,11 @@ var AST_Switch = DEFNODE("Switch", "expression", {
 }, AST_Block);
 
 var AST_SwitchBranch = DEFNODE("SwitchBranch", null, {
-    $documentation: "Base class for `switch` branches",
+    $documentation: "Base class for `switch` branches"
 }, AST_Block);
 
 var AST_Default = DEFNODE("Default", null, {
-    $documentation: "A `default` switch branch",
+    $documentation: "A `default` switch branch"
 }, AST_SwitchBranch);
 
 var AST_Case = DEFNODE("Case", "expression", {
@@ -720,7 +720,7 @@ var AST_Conditional = DEFNODE("Conditional", "condition consequent alternative",
 });
 
 var AST_Assign = DEFNODE("Assign", null, {
-    $documentation: "An assignment expression — `a = b + 5`",
+    $documentation: "An assignment expression — `a = b + 5`"
 }, AST_Binary);
 
 /* -----[ LITERALS ]----- */
@@ -767,15 +767,15 @@ var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
 });
 
 var AST_ObjectKeyVal = DEFNODE("ObjectKeyVal", null, {
-    $documentation: "A key: value object property",
+    $documentation: "A key: value object property"
 }, AST_ObjectProperty);
 
 var AST_ObjectSetter = DEFNODE("ObjectSetter", null, {
-    $documentation: "An object setter property",
+    $documentation: "An object setter property"
 }, AST_ObjectProperty);
 
 var AST_ObjectGetter = DEFNODE("ObjectGetter", null, {
-    $documentation: "An object getter property",
+    $documentation: "An object getter property"
 }, AST_ObjectProperty);
 
 var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
@@ -784,7 +784,7 @@ var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
         scope: "[AST_Scope/S] the current scope (not necessarily the definition scope)",
         thedef: "[SymbolDef/S] the definition of this symbol"
     },
-    $documentation: "Base class for all symbols",
+    $documentation: "Base class for all symbols"
 });
 
 var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
@@ -799,7 +799,7 @@ var AST_SymbolDeclaration = DEFNODE("SymbolDeclaration", "init", {
 }, AST_Symbol);
 
 var AST_SymbolVar = DEFNODE("SymbolVar", null, {
-    $documentation: "Symbol defining a variable",
+    $documentation: "Symbol defining a variable"
 }, AST_SymbolDeclaration);
 
 var AST_SymbolConst = DEFNODE("SymbolConst", null, {
@@ -807,19 +807,19 @@ var AST_SymbolConst = DEFNODE("SymbolConst", null, {
 }, AST_SymbolDeclaration);
 
 var AST_SymbolFunarg = DEFNODE("SymbolFunarg", null, {
-    $documentation: "Symbol naming a function argument",
+    $documentation: "Symbol naming a function argument"
 }, AST_SymbolVar);
 
 var AST_SymbolDefun = DEFNODE("SymbolDefun", null, {
-    $documentation: "Symbol defining a function",
+    $documentation: "Symbol defining a function"
 }, AST_SymbolDeclaration);
 
 var AST_SymbolLambda = DEFNODE("SymbolLambda", null, {
-    $documentation: "Symbol naming a function expression",
+    $documentation: "Symbol naming a function expression"
 }, AST_SymbolDeclaration);
 
 var AST_SymbolCatch = DEFNODE("SymbolCatch", null, {
-    $documentation: "Symbol naming the exception in catch",
+    $documentation: "Symbol naming the exception in catch"
 }, AST_SymbolDeclaration);
 
 var AST_Label = DEFNODE("Label", "references", {
@@ -834,15 +834,15 @@ var AST_Label = DEFNODE("Label", "references", {
 }, AST_Symbol);
 
 var AST_SymbolRef = DEFNODE("SymbolRef", null, {
-    $documentation: "Reference to some symbol (not definition/declaration)",
+    $documentation: "Reference to some symbol (not definition/declaration)"
 }, AST_Symbol);
 
 var AST_LabelRef = DEFNODE("LabelRef", null, {
-    $documentation: "Reference to a label symbol",
+    $documentation: "Reference to a label symbol"
 }, AST_Symbol);
 
 var AST_This = DEFNODE("This", null, {
-    $documentation: "The `this` symbol",
+    $documentation: "The `this` symbol"
 }, AST_Symbol);
 
 var AST_Constant = DEFNODE("Constant", null, {
@@ -874,7 +874,7 @@ var AST_RegExp = DEFNODE("RegExp", "value", {
 }, AST_Constant);
 
 var AST_Atom = DEFNODE("Atom", null, {
-    $documentation: "Base class for atoms",
+    $documentation: "Base class for atoms"
 }, AST_Constant);
 
 var AST_Null = DEFNODE("Null", null, {
@@ -903,7 +903,7 @@ var AST_Infinity = DEFNODE("Infinity", null, {
 }, AST_Atom);
 
 var AST_Boolean = DEFNODE("Boolean", null, {
-    $documentation: "Base class for booleans",
+    $documentation: "Base class for booleans"
 }, AST_Atom);
 
 var AST_False = DEFNODE("False", null, {
diff --git a/lib/compress.js b/lib/compress.js
index d503ed17..edc17e2b 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1350,7 +1350,7 @@ merge(Compressor.prototype, {
                     self.condition = make_node(AST_Binary, self.condition, {
                         left: self.condition,
                         operator: "&&",
-                        right: first.condition.negate(compressor),
+                        right: first.condition.negate(compressor)
                     });
                 } else {
                     self.condition = first.condition.negate(compressor);
@@ -1363,7 +1363,7 @@ merge(Compressor.prototype, {
                     self.condition = make_node(AST_Binary, self.condition, {
                         left: self.condition,
                         operator: "&&",
-                        right: first.condition,
+                        right: first.condition
                     });
                 } else {
                     self.condition = first.condition;
@@ -1820,7 +1820,7 @@ merge(Compressor.prototype, {
                         return make_node(AST_Binary, el[0], {
                             operator : "+",
                             left     : prev,
-                            right    : el[0],
+                            right    : el[0]
                         });
                     }, first).transform(compressor);
                 }
@@ -2369,7 +2369,7 @@ merge(Compressor.prototype, {
                     value    : self.value,
                     file     : p.start.file,
                     line     : p.start.line,
-                    col      : p.start.col,
+                    col      : p.start.col
                 });
                 return make_node(AST_Number, self, {
                     value: +self.value
diff --git a/lib/output.js b/lib/output.js
index 72bcdd5e..bf636509 100644
--- a/lib/output.js
+++ b/lib/output.js
@@ -62,7 +62,7 @@ function OutputStream(options) {
         comments         : false,
         preserve_line    : false,
         screw_ie8        : false,
-        preamble         : null,
+        preamble         : null
     }, true);
 
     var indentation = 0;
@@ -187,12 +187,15 @@ function OutputStream(options) {
             }
             might_need_space = false;
         }
-        var a = str.split(/\r?\n/), n = a.length - 1;
-        current_line += n;
-        if (n == 0) {
-            current_col += a[n].length;
-        } else {
-            current_col = a[n].length;
+        var a = str.split(/\r?\n/), len = a.length;
+        if (len > 0) {
+            var n = len - 1;
+            current_line += n;
+            if (n == 0) {
+                current_col += a[n].length;
+            } else {
+                current_col = a[n].length;
+            }
         }
         current_pos += str.length;
         last = str;
diff --git a/lib/parse.js b/lib/parse.js
index f463526f..32b429f6 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -617,7 +617,7 @@ function parse($TEXT, options) {
         toplevel       : null,
         expression     : false,
         html5_comments : true,
-        bare_returns   : false,
+        bare_returns   : false
     });
 
     var S = {
diff --git a/lib/sourcemap.js b/lib/sourcemap.js
index 3998e405..9ad15844 100644
--- a/lib/sourcemap.js
+++ b/lib/sourcemap.js
@@ -51,7 +51,7 @@ function SourceMap(options) {
         orig : null,
 
         orig_line_diff : 0,
-        dest_line_diff : 0,
+        dest_line_diff : 0
     });
     var orig_map = options.orig && new MOZ_SourceMap.SourceMapConsumer(options.orig);
     var generator;