diff --git a/lib/compress.js b/lib/compress.js
index 12b87dd23ce..f6419954f52 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2791,7 +2791,7 @@ merge(Compressor.prototype, {
                     if (self.args.length != 1) {
                         return make_node(AST_Array, self, {
                             elements: self.args
-                        }).transform(compressor);
+                        }).optimize(compressor);
                     }
                     break;
                   case "Object":
@@ -2809,7 +2809,7 @@ merge(Compressor.prototype, {
                         left: self.args[0],
                         operator: "+",
                         right: make_node(AST_String, self, { value: "" })
-                    }).transform(compressor);
+                    }).optimize(compressor);
                     break;
                   case "Number":
                     if (self.args.length == 0) return make_node(AST_Number, self, {
@@ -2818,7 +2818,7 @@ merge(Compressor.prototype, {
                     if (self.args.length == 1) return make_node(AST_UnaryPrefix, self, {
                         expression: self.args[0],
                         operator: "+"
-                    }).transform(compressor);
+                    }).optimize(compressor);
                   case "Boolean":
                     if (self.args.length == 0) return make_node(AST_False, self);
                     if (self.args.length == 1) return make_node(AST_UnaryPrefix, self, {
@@ -2827,7 +2827,7 @@ merge(Compressor.prototype, {
                             operator: "!"
                         }),
                         operator: "!"
-                    }).transform(compressor);
+                    }).optimize(compressor);
                     break;
                   case "Function":
                     // new Function() => function(){}
@@ -2897,7 +2897,7 @@ merge(Compressor.prototype, {
                     left: make_node(AST_String, self, { value: "" }),
                     operator: "+",
                     right: exp.expression
-                }).transform(compressor);
+                }).optimize(compressor);
             }
             else if (exp instanceof AST_Dot && exp.expression instanceof AST_Array && exp.property == "join") EXIT: {
                 var separator;
@@ -2951,7 +2951,7 @@ merge(Compressor.prototype, {
                             left     : prev,
                             right    : el
                         });
-                    }, first).transform(compressor);
+                    }, first).optimize(compressor);
                 }
                 // need this awkward cloning to not affect original element
                 // best_of will decide which one to get through.
@@ -2961,6 +2961,16 @@ merge(Compressor.prototype, {
                 node.expression.expression.elements = elements;
                 return best_of(compressor, self, node);
             }
+            else if (exp instanceof AST_Dot && exp.expression.is_string(compressor) && exp.property == "charAt") {
+                var arg = self.args[0];
+                var index = arg ? arg.evaluate(compressor) : 0;
+                if (index !== arg) {
+                    return make_node(AST_Sub, exp, {
+                        expression: exp.expression,
+                        property: make_node_from_constant(index | 0, arg || exp)
+                    }).optimize(compressor);
+                }
+            }
         }
         if (exp instanceof AST_Function && !self.expression.is_generator) {
             if (exp.body[0] instanceof AST_Return) {
@@ -3129,14 +3139,6 @@ merge(Compressor.prototype, {
         return self;
     });
 
-    function has_side_effects_or_prop_access(node, compressor) {
-        var save_pure_getters = compressor.option("pure_getters");
-        compressor.options.pure_getters = false;
-        var ret = node.has_side_effects(compressor);
-        compressor.options.pure_getters = save_pure_getters;
-        return ret;
-    }
-
     AST_Binary.DEFMETHOD("lift_sequences", function(compressor){
         if (compressor.option("sequences")) {
             if (this.left instanceof AST_Seq) {
@@ -3144,18 +3146,23 @@ merge(Compressor.prototype, {
                 var x = seq.to_array();
                 this.left = x.pop();
                 x.push(this);
-                seq = AST_Seq.from_array(x).transform(compressor);
-                return seq;
-            }
-            if (this.right instanceof AST_Seq
-                && this instanceof AST_Assign
-                && !has_side_effects_or_prop_access(this.left, compressor)) {
-                var seq = this.right;
-                var x = seq.to_array();
-                this.right = x.pop();
-                x.push(this);
-                seq = AST_Seq.from_array(x).transform(compressor);
-                return seq;
+                return AST_Seq.from_array(x).optimize(compressor);
+            }
+            if (this.right instanceof AST_Seq && !this.left.has_side_effects(compressor)) {
+                var assign = this.operator == "=" && this.left instanceof AST_SymbolRef;
+                var root = this.right;
+                var cursor, seq = root;
+                while (assign || !seq.car.has_side_effects(compressor)) {
+                    cursor = seq;
+                    if (seq.cdr instanceof AST_Seq) {
+                        seq = seq.cdr;
+                    } else break;
+                }
+                if (cursor) {
+                    this.right = cursor.cdr;
+                    cursor.cdr = this;
+                    return root.optimize(compressor);
+                }
             }
         }
         return this;
@@ -3190,32 +3197,6 @@ merge(Compressor.prototype, {
                     reverse();
                 }
             }
-            if (/^[!=]==?$/.test(self.operator)) {
-                if (self.left instanceof AST_SymbolRef && self.right instanceof AST_Conditional) {
-                    if (self.right.consequent instanceof AST_SymbolRef
-                        && self.right.consequent.definition() === self.left.definition()) {
-                        if (/^==/.test(self.operator)) return self.right.condition;
-                        if (/^!=/.test(self.operator)) return self.right.condition.negate(compressor);
-                    }
-                    if (self.right.alternative instanceof AST_SymbolRef
-                        && self.right.alternative.definition() === self.left.definition()) {
-                        if (/^==/.test(self.operator)) return self.right.condition.negate(compressor);
-                        if (/^!=/.test(self.operator)) return self.right.condition;
-                    }
-                }
-                if (self.right instanceof AST_SymbolRef && self.left instanceof AST_Conditional) {
-                    if (self.left.consequent instanceof AST_SymbolRef
-                        && self.left.consequent.definition() === self.right.definition()) {
-                        if (/^==/.test(self.operator)) return self.left.condition;
-                        if (/^!=/.test(self.operator)) return self.left.condition.negate(compressor);
-                    }
-                    if (self.left.alternative instanceof AST_SymbolRef
-                        && self.left.alternative.definition() === self.right.definition()) {
-                        if (/^==/.test(self.operator)) return self.left.condition.negate(compressor);
-                        if (/^!=/.test(self.operator)) return self.left.condition;
-                    }
-                }
-            }
         }
         self = self.lift_sequences(compressor);
         if (compressor.option("comparisons")) switch (self.operator) {
diff --git a/package.json b/package.json
index 34b1674a01a..ab0b87e3335 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "2.8.13",
+  "version": "2.8.14",
   "engines": {
     "node": ">=0.8.0"
   },
diff --git a/test/compress/collapse_vars.js b/test/compress/collapse_vars.js
index f46175ddaba..acca9bedf48 100644
--- a/test/compress/collapse_vars.js
+++ b/test/compress/collapse_vars.js
@@ -43,6 +43,7 @@ collapse_vars_side_effects_1: {
                 z = i += 4;
             log(x, z, y, i);
         }
+        f1(), f2(), f3(), f4();
     }
     expect: {
         function f1() {
@@ -73,7 +74,9 @@ collapse_vars_side_effects_1: {
                 y = i += 3;
             log(x, i += 4, y, i);
         }
+        f1(), f2(), f3(), f4();
     }
+    expect_stdout: true
 }
 
 collapse_vars_side_effects_2: {
@@ -823,6 +826,7 @@ collapse_vars_repeated: {
             console.log(e + "!");
         })("!");
     }
+    expect_stdout: true
 }
 
 collapse_vars_closures: {
@@ -1109,6 +1113,7 @@ collapse_vars_eval_and_with: {
             return function() { with (o) console.log(a) };
         })()();
     }
+    expect_stdout: true
 }
 
 collapse_vars_constants: {
@@ -1168,6 +1173,7 @@ collapse_vars_arguments: {
             (function(){console.log(arguments);})(7, 1);
         })();
     }
+    expect_stdout: true
 }
 
 collapse_vars_short_circuit: {
@@ -1317,6 +1323,7 @@ collapse_vars_regexp: {
                 console.log(result[0]);
         })();
     }
+    expect_stdout: true
 }
 
 issue_1537: {
diff --git a/test/compress/concat-strings.js b/test/compress/concat-strings.js
index 2f99375c4fc..867951ff692 100644
--- a/test/compress/concat-strings.js
+++ b/test/compress/concat-strings.js
@@ -51,6 +51,7 @@ concat_2: {
             "1" + "2" + "3"
         );
     }
+    expect_stdout: true
 }
 
 concat_3: {
@@ -79,6 +80,7 @@ concat_3: {
             1 + 2 + "3" + "4" + "5"
         );
     }
+    expect_stdout: true
 }
 
 concat_4: {
@@ -107,6 +109,7 @@ concat_4: {
             1 + "2" + "3" + "4" + "5"
         );
     }
+    expect_stdout: true
 }
 
 concat_5: {
@@ -135,6 +138,7 @@ concat_5: {
             "1" + 2 + "3" + "4" + "5"
         );
     }
+    expect_stdout: true
 }
 
 concat_6: {
@@ -163,6 +167,7 @@ concat_6: {
             "1" + "2" + "3" + "4" + "5"
         );
     }
+    expect_stdout: true
 }
 
 concat_7: {
@@ -188,6 +193,7 @@ concat_7: {
             x += "foo"
         );
     }
+    expect_stdout: true
 }
 
 concat_8: {
@@ -213,4 +219,5 @@ concat_8: {
             x += "foo"
         );
     }
+    expect_stdout: true
 }
diff --git a/test/compress/conditionals.js b/test/compress/conditionals.js
index 074d2a651eb..7c81cc80a95 100644
--- a/test/compress/conditionals.js
+++ b/test/compress/conditionals.js
@@ -797,3 +797,99 @@ no_evaluate: {
         }
     }
 }
+
+equality_conditionals_false: {
+    options = {
+        conditionals: false,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0);
+        f(0, true, 0);
+        f(1, 2, 3);
+        f(1, null, 3);
+        f(NaN);
+        f(NaN, "foo");
+    }
+    expect: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0),
+        f(0, true, 0),
+        f(1, 2, 3),
+        f(1, null, 3),
+        f(NaN),
+        f(NaN, "foo");
+    }
+    expect_stdout: true
+}
+
+equality_conditionals_true: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c) {
+            console.log(
+                a == (b ? a : a),
+                a == (b ? a : c),
+                a != (b ? a : a),
+                a != (b ? a : c),
+                a === (b ? a : a),
+                a === (b ? a : c),
+                a !== (b ? a : a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0);
+        f(0, true, 0);
+        f(1, 2, 3);
+        f(1, null, 3);
+        f(NaN);
+        f(NaN, "foo");
+    }
+    expect: {
+        function f(a, b, c) {
+            console.log(
+                (b, a == a),
+                a == (b ? a : c),
+                (b, a != a),
+                a != (b ? a : c),
+                (b, a === a),
+                a === (b ? a : c),
+                (b, a !== a),
+                a !== (b ? a : c)
+            );
+        }
+        f(0, 0, 0),
+        f(0, true, 0),
+        f(1, 2, 3),
+        f(1, null, 3),
+        f(NaN),
+        f(NaN, "foo");
+    }
+    expect_stdout: true
+}
diff --git a/test/compress/const.js b/test/compress/const.js
index f1f13f4998d..a88d5946717 100644
--- a/test/compress/const.js
+++ b/test/compress/const.js
@@ -162,4 +162,5 @@ regexp_literal_not_const: {
             while (result = REGEXP_LITERAL.exec("acdabcdeabbb")) console.log(result[0]);
         })();
     }
+    expect_stdout: true
 }
diff --git a/test/compress/dead-code.js b/test/compress/dead-code.js
index fa52496d739..da1b1838911 100644
--- a/test/compress/dead-code.js
+++ b/test/compress/dead-code.js
@@ -87,6 +87,7 @@ dead_code_constant_boolean_should_warn_more: {
         var x = 10, y;
         var moo;
     }
+    expect_stdout: true
 }
 
 dead_code_block_decls_die: {
@@ -135,6 +136,7 @@ dead_code_const_declaration: {
         var moo;
         function bar() {}
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation: {
@@ -162,6 +164,7 @@ dead_code_const_annotation: {
         var moo;
         function bar() {}
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation_regex: {
@@ -185,6 +188,7 @@ dead_code_const_annotation_regex: {
         var CONST_FOO_ANN = !1;
         CONST_FOO_ANN && console.log('reachable');
     }
+    expect_stdout: true
 }
 
 dead_code_const_annotation_complex_scope: {
@@ -230,4 +234,5 @@ dead_code_const_annotation_complex_scope: {
         var meat = 'beef';
         var pork = 'bad';
     }
+    expect_stdout: true
 }
diff --git a/test/compress/evaluate.js b/test/compress/evaluate.js
index 5adbc9ea11b..6b8f0826383 100644
--- a/test/compress/evaluate.js
+++ b/test/compress/evaluate.js
@@ -200,6 +200,7 @@ negative_zero: {
             1 / (-0)
         );
     }
+    expect_stdout: true
 }
 
 positive_zero: {
@@ -220,6 +221,7 @@ positive_zero: {
             1 / (0)
         );
     }
+    expect_stdout: true
 }
 
 pow: {
@@ -337,6 +339,7 @@ unsafe_constant: {
             (void 0).a
         );
     }
+    expect_stdout: true
 }
 
 unsafe_object: {
@@ -360,6 +363,7 @@ unsafe_object: {
             1..b + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_object_nested: {
@@ -383,6 +387,7 @@ unsafe_object_nested: {
             2
         );
     }
+    expect_stdout: true
 }
 
 unsafe_object_complex: {
@@ -406,6 +411,7 @@ unsafe_object_complex: {
             2
         );
     }
+    expect_stdout: true
 }
 
 unsafe_object_repeated: {
@@ -429,6 +435,7 @@ unsafe_object_repeated: {
             1..b + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_object_accessor: {
@@ -478,6 +485,7 @@ unsafe_function: {
             ({a:{b:1},b:function(){}}).a.b + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_integer_key: {
@@ -505,6 +513,7 @@ unsafe_integer_key: {
             1["1"] + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_integer_key_complex: {
@@ -532,6 +541,7 @@ unsafe_integer_key_complex: {
             2
         );
     }
+    expect_stdout: true
 }
 
 unsafe_float_key: {
@@ -559,6 +569,7 @@ unsafe_float_key: {
             1["3.14"] + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_float_key_complex: {
@@ -586,6 +597,7 @@ unsafe_float_key_complex: {
             2
         );
     }
+    expect_stdout: true
 }
 
 unsafe_array: {
@@ -621,6 +633,7 @@ unsafe_array: {
             (void 0)[1] + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_string: {
@@ -648,6 +661,7 @@ unsafe_string: {
             "11"
         );
     }
+    expect_stdout: true
 }
 
 unsafe_array_bad_index: {
@@ -669,6 +683,7 @@ unsafe_array_bad_index: {
             [1, 2, 3, 4][3.14] + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_string_bad_index: {
@@ -690,6 +705,7 @@ unsafe_string_bad_index: {
             "1234"[3.14] + 1
         );
     }
+    expect_stdout: true
 }
 
 unsafe_prototype_function: {
@@ -736,6 +752,7 @@ call_args: {
         console.log(1);
         +(1, 1);
     }
+    expect_stdout: true
 }
 
 call_args_drop_param: {
@@ -757,6 +774,7 @@ call_args_drop_param: {
         console.log(1);
         +(b, 1);
     }
+    expect_stdout: true
 }
 
 in_boolean_context: {
@@ -794,4 +812,74 @@ in_boolean_context: {
             (foo(), !1)
         );
     }
+    expect_stdout: true
+}
+
+unsafe_charAt: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234" + 1,
+            "1234".charAt(0) + 1,
+            "1234".charAt(6 - 5) + 1,
+            ("12" + "34").charAt(0) + 1,
+            ("12" + "34").charAt(6 - 5) + 1,
+            [1, 2, 3, 4].join("").charAt(0) + 1
+        );
+    }
+    expect: {
+        console.log(
+            "12341",
+            "11",
+            "21",
+            "11",
+            "21",
+            "11"
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_charAt_bad_index: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            "1234".charAt() + 1,
+            "1234".charAt("a") + 1,
+            "1234".charAt(3.14) + 1
+        );
+    }
+    expect: {
+        console.log(
+            "11",
+            "11",
+            "41"
+        );
+    }
+    expect_stdout: true
+}
+
+unsafe_charAt_noop: {
+    options = {
+        evaluate  : true,
+        unsafe    : true
+    }
+    input: {
+        console.log(
+            s.charAt(0),
+            "string".charAt(x)
+        );
+    }
+    expect: {
+        console.log(
+            s.charAt(0),
+            "string".charAt(x)
+        );
+    }
 }
diff --git a/test/compress/functions.js b/test/compress/functions.js
index a1a515a13d0..dca40623540 100644
--- a/test/compress/functions.js
+++ b/test/compress/functions.js
@@ -39,6 +39,7 @@ iifes_returning_constants_keep_fargs_true: {
         console.log(6);
         console.log((a(), b(), 6));
     }
+    expect_stdout: true
 }
 
 iifes_returning_constants_keep_fargs_false: {
@@ -73,6 +74,7 @@ iifes_returning_constants_keep_fargs_false: {
         console.log(6);
         console.log((a(), b(), 6));
     }
+    expect_stdout: true
 }
 
 issue_485_crashing_1530: {
diff --git a/test/compress/issue-1275.js b/test/compress/issue-1275.js
index 51f696afc25..5d4f5b706eb 100644
--- a/test/compress/issue-1275.js
+++ b/test/compress/issue-1275.js
@@ -46,4 +46,5 @@ string_plus_optimization: {
         }
         foo();
     }
+    expect_stdout: true
 }
diff --git a/test/compress/issue-1321.js b/test/compress/issue-1321.js
index 2b6f17bfd6d..7449d3e2b32 100644
--- a/test/compress/issue-1321.js
+++ b/test/compress/issue-1321.js
@@ -14,6 +14,7 @@ issue_1321_no_debug: {
         x["a"] = 2 * x.b;
         console.log(x.b, x["a"]);
     }
+    expect_stdout: true
 }
 
 issue_1321_debug: {
@@ -33,6 +34,7 @@ issue_1321_debug: {
         x["_$foo$_"] = 2 * x.a;
         console.log(x.a, x["_$foo$_"]);
     }
+    expect_stdout: true
 }
 
 issue_1321_with_quoted: {
@@ -51,4 +53,5 @@ issue_1321_with_quoted: {
         x["b"] = 2 * x.a;
         console.log(x.a, x["b"]);
     }
+    expect_stdout: true
 }
diff --git a/test/compress/issue-1447.js b/test/compress/issue-1447.js
index 163acbc218e..a7f35e5a434 100644
--- a/test/compress/issue-1447.js
+++ b/test/compress/issue-1447.js
@@ -42,4 +42,5 @@ conditional_false_stray_else_in_loop: {
         }
     }
     expect_exact: "for(var i=1;i<=4;++i)if(!(i<=2))console.log(i);"
+    expect_stdout: true
 }
diff --git a/test/compress/issue-1466.js b/test/compress/issue-1466.js
index 5a323c48c80..9273235b79e 100644
--- a/test/compress/issue-1466.js
+++ b/test/compress/issue-1466.js
@@ -13,9 +13,9 @@ same_variable_in_multiple_for_loop: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         for (let i = 0; i < 3; i++) {
             let a = 100;
@@ -38,6 +38,7 @@ same_variable_in_multiple_for_loop: {
             }
         }
     }
+    expect_stdout: true
 }
 
 same_variable_in_multiple_forOf: {
@@ -55,9 +56,9 @@ same_variable_in_multiple_forOf: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         var test = [ "a", "b", "c" ];
         for (let tmp of test) {
@@ -75,10 +76,11 @@ same_variable_in_multiple_forOf: {
             console.log(o);
             let e;
             e = [ "e", "f", "g" ];
-            for (let o of e) 
+            for (let o of e)
                 console.log(o);
         }
     }
+    expect_stdout: true
 }
 
 same_variable_in_multiple_forIn: {
@@ -96,9 +98,9 @@ same_variable_in_multiple_forIn: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         var test = [ "a", "b", "c" ];
         for (let tmp in test) {
@@ -120,6 +122,7 @@ same_variable_in_multiple_forIn: {
                 console.log(o);
         }
     }
+    expect_stdout: true
 }
 
 different_variable_in_multiple_for_loop: {
@@ -137,9 +140,9 @@ different_variable_in_multiple_for_loop: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         for (let i = 0; i < 3; i++) {
             let a = 100;
@@ -162,6 +165,7 @@ different_variable_in_multiple_for_loop: {
             }
         }
     }
+    expect_stdout: true
 }
 
 different_variable_in_multiple_forOf: {
@@ -179,9 +183,9 @@ different_variable_in_multiple_forOf: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         var test = [ "a", "b", "c" ];
         for (let tmp of test) {
@@ -203,6 +207,7 @@ different_variable_in_multiple_forOf: {
                 console.log(o);
         }
     }
+    expect_stdout: true
 }
 
 different_variable_in_multiple_forIn: {
@@ -220,9 +225,9 @@ different_variable_in_multiple_forIn: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         var test = [ "a", "b", "c" ];
         for (let tmp in test) {
@@ -244,6 +249,7 @@ different_variable_in_multiple_forIn: {
                 console.log(o);
         }
     }
+    expect_stdout: true
 }
 
 more_variable_in_multiple_for: {
@@ -261,9 +267,9 @@ more_variable_in_multiple_for: {
         join_vars: true,
         cascade: true,
         side_effects: true,
-        collapse_vars: true
-    };
-    mangle = {};
+        collapse_vars: true,
+    }
+    mangle = {}
     input: {
         for (let a = 9, i = 0; i < 20; i += a) {
             let b = a++ + i;
@@ -281,5 +287,5 @@ more_variable_in_multiple_for: {
                 console.log(o, c, e, l, f);
         }
     }
+    expect_stdout: true
 }
-
diff --git a/test/compress/issue-640.js b/test/compress/issue-640.js
index dd3f3f2196a..fbf5f37fb05 100644
--- a/test/compress/issue-640.js
+++ b/test/compress/issue-640.js
@@ -48,6 +48,7 @@ dead_code_const_annotation_regex: {
         var CONST_FOO_ANN = !1;
         if (CONST_FOO_ANN) console.log('reachable');
     }
+    expect_stdout: true
 }
 
 drop_console_2: {
@@ -225,6 +226,7 @@ issue_1254_negate_iife_true: {
         })()();
     }
     expect_exact: '(function(){return function(){console.log("test")}})()();'
+    expect_stdout: true
 }
 
 issue_1254_negate_iife_nested: {
@@ -240,6 +242,7 @@ issue_1254_negate_iife_nested: {
         })()()()()();
     }
     expect_exact: '(function(){return function(){console.log("test")}})()()()()();'
+    expect_stdout: true
 }
 
 conditional: {
diff --git a/test/compress/issue-892.js b/test/compress/issue-892.js
index 2dab420f045..b6938c42ed7 100644
--- a/test/compress/issue-892.js
+++ b/test/compress/issue-892.js
@@ -29,4 +29,5 @@ dont_mangle_arguments: {
         })(5,6,7);
     }
     expect_exact: "(function(){var arguments=arguments,o=9;console.log(o,arguments)})(5,6,7);"
+    expect_stdout: true
 }
diff --git a/test/compress/issue-976.js b/test/compress/issue-976.js
index 06e11f40a31..b711051b09e 100644
--- a/test/compress/issue-976.js
+++ b/test/compress/issue-976.js
@@ -42,6 +42,7 @@ eval_collapse_vars: {
             eval("console.log(a);");
         })(eval);
     }
+    expect_stdout: true
 }
 
 eval_unused: {
diff --git a/test/compress/labels.js b/test/compress/labels.js
index 044b7a7eabc..0d85d10ad93 100644
--- a/test/compress/labels.js
+++ b/test/compress/labels.js
@@ -9,6 +9,7 @@ labels_1: {
     expect: {
         foo || console.log("bar");
     }
+    expect_stdout: true
 }
 
 labels_2: {
@@ -40,6 +41,7 @@ labels_3: {
         for (var i = 0; i < 5; ++i)
             i < 3 || console.log(i);
     }
+    expect_stdout: true
 }
 
 labels_4: {
@@ -54,6 +56,7 @@ labels_4: {
         for (var i = 0; i < 5; ++i)
             i < 3 || console.log(i);
     }
+    expect_stdout: true
 }
 
 labels_5: {
diff --git a/test/compress/loops.js b/test/compress/loops.js
index 7581e7585b3..b55c616240f 100644
--- a/test/compress/loops.js
+++ b/test/compress/loops.js
@@ -166,6 +166,7 @@ keep_collapse_const_in_own_block_scope: {
             console.log(i);
         console.log(c);
     }
+    expect_stdout: true
 }
 
 keep_collapse_const_in_own_block_scope_2: {
@@ -186,6 +187,7 @@ keep_collapse_const_in_own_block_scope_2: {
             console.log(i);
         console.log(c);
     }
+    expect_stdout: true
 }
 
 evaluate: {
diff --git a/test/compress/negate-iife.js b/test/compress/negate-iife.js
index 9a0b5a46867..e9ad37db5d4 100644
--- a/test/compress/negate-iife.js
+++ b/test/compress/negate-iife.js
@@ -70,6 +70,7 @@ negate_iife_3_evaluate: {
     expect: {
         console.log(true);
     }
+    expect_stdout: true
 }
 
 negate_iife_3_side_effects: {
@@ -111,6 +112,7 @@ negate_iife_3_off_evaluate: {
     expect: {
         console.log(true);
     }
+    expect_stdout: true
 }
 
 negate_iife_4: {
@@ -243,6 +245,7 @@ negate_iife_nested: {
             }(7);
         }).f();
     }
+    expect_stdout: true
 }
 
 negate_iife_nested_off: {
@@ -275,6 +278,7 @@ negate_iife_nested_off: {
             })(7);
         }).f();
     }
+    expect_stdout: true
 }
 
 negate_iife_issue_1073: {
@@ -299,6 +303,7 @@ negate_iife_issue_1073: {
             };
         }(7))();
     }
+    expect_stdout: true
 }
 
 issue_1254_negate_iife_false: {
@@ -313,6 +318,7 @@ issue_1254_negate_iife_false: {
         })()();
     }
     expect_exact: '(function(){return function(){console.log("test")}})()();'
+    expect_stdout: true
 }
 
 issue_1254_negate_iife_true: {
@@ -327,6 +333,7 @@ issue_1254_negate_iife_true: {
         })()();
     }
     expect_exact: '!function(){return function(){console.log("test")}}()();'
+    expect_stdout: true
 }
 
 issue_1254_negate_iife_nested: {
@@ -341,6 +348,7 @@ issue_1254_negate_iife_nested: {
         })()()()()();
     }
     expect_exact: '!function(){return function(){console.log("test")}}()()()()();'
+    expect_stdout: true
 }
 
 issue_1288: {
diff --git a/test/compress/reduce_vars.js b/test/compress/reduce_vars.js
index bc6c72d473c..3d5612cfbb4 100644
--- a/test/compress/reduce_vars.js
+++ b/test/compress/reduce_vars.js
@@ -58,6 +58,7 @@ reduce_vars: {
         })();
         console.log(2);
     }
+    expect_stdout: true
 }
 
 modified: {
@@ -166,7 +167,7 @@ modified: {
             console.log(A ? 'yes' : 'no');
             console.log(B ? 'yes' : 'no');
         }
-   }
+    }
 }
 
 unsafe_evaluate: {
@@ -401,6 +402,7 @@ iife: {
             console.log(0, 1 * b, 5);
         }(1, 2, 3);
     }
+    expect_stdout: true
 }
 
 iife_new: {
@@ -420,6 +422,7 @@ iife_new: {
             console.log(0, 1 * b, 5);
         }(1, 2, 3);
     }
+    expect_stdout: true
 }
 
 multi_def: {
@@ -707,6 +710,7 @@ toplevel_on: {
     expect: {
         console.log(3);
     }
+    expect_stdout: true
 }
 
 toplevel_off: {
@@ -724,6 +728,7 @@ toplevel_off: {
         var x = 3;
         console.log(x);
     }
+    expect_stdout: true
 }
 
 toplevel_on_loops_1: {
@@ -751,6 +756,7 @@ toplevel_on_loops_1: {
             })();
         while (x);
     }
+    expect_stdout: true
 }
 
 toplevel_off_loops_1: {
@@ -779,6 +785,7 @@ toplevel_off_loops_1: {
             bar();
         while (x);
     }
+    expect_stdout: true
 }
 
 toplevel_on_loops_2: {
@@ -1121,6 +1128,7 @@ defun_label: {
             }(2));
         }();
     }
+    expect_stdout: true
 }
 
 double_reference: {
@@ -1164,6 +1172,7 @@ iife_arguments_1: {
             return f;
         });
     }
+    expect_stdout: true
 }
 
 iife_arguments_2: {
@@ -1186,6 +1195,7 @@ iife_arguments_2: {
             }() === arguments[0]);
         })();
     }
+    expect_stdout: true
 }
 
 iife_eval_1: {
@@ -1207,6 +1217,7 @@ iife_eval_1: {
             return f;
         });
     }
+    expect_stdout: true
 }
 
 iife_eval_2: {
@@ -1230,6 +1241,7 @@ iife_eval_2: {
             console.log(x() === eval("x"));
         })();
     }
+    expect_stdout: true
 }
 
 iife_func_side_effects: {
@@ -1326,6 +1338,7 @@ issue_1595_4: {
             if (a) iife(a - 1, b, c);
         })(3, 4, 5);
     }
+    expect_stdout: true
 }
 
 issue_1606: {
diff --git a/test/compress/screw-ie8.js b/test/compress/screw-ie8.js
index 0fb68c25530..fc492112db6 100644
--- a/test/compress/screw-ie8.js
+++ b/test/compress/screw-ie8.js
@@ -128,6 +128,7 @@ do_screw_try_catch_undefined: {
             return void 0===o
         }
     }
+    expect_stdout: true
 }
 
 dont_screw_try_catch_undefined: {
@@ -156,6 +157,7 @@ dont_screw_try_catch_undefined: {
             return n === undefined
         }
     }
+    expect_stdout: true
 }
 
 reduce_vars: {
@@ -208,6 +210,7 @@ issue_1586_1: {
         }
     }
     expect_exact: "function f(){try{}catch(c){console.log(c.message)}}"
+    expect_stdout: true
 }
 
 issue_1586_2: {
@@ -226,4 +229,5 @@ issue_1586_2: {
         }
     }
     expect_exact: "function f(){try{}catch(c){console.log(c.message)}}"
+    expect_stdout: true
 }
diff --git a/test/compress/sequences.js b/test/compress/sequences.js
index 41cfc726159..49b61ae0f9c 100644
--- a/test/compress/sequences.js
+++ b/test/compress/sequences.js
@@ -86,6 +86,7 @@ make_sequences_4: {
         switch (x = 5, y) {}
         with (x = 5, obj);
     }
+    expect_stdout: true
 }
 
 lift_sequences_1: {
@@ -103,15 +104,18 @@ lift_sequences_1: {
 lift_sequences_2: {
     options = { sequences: true, evaluate: true };
     input: {
-        var foo, bar;
+        var foo = 1, bar;
         foo.x = (foo = {}, 10);
         bar = (bar = {}, 10);
+        console.log(foo, bar);
     }
     expect: {
-        var foo, bar;
+        var foo = 1, bar;
         foo.x = (foo = {}, 10),
-        bar = {}, bar = 10;
+        bar = {}, bar = 10,
+        console.log(foo, bar);
     }
+    expect_stdout: true
 }
 
 lift_sequences_3: {
@@ -138,6 +142,23 @@ lift_sequences_4: {
     }
 }
 
+lift_sequences_5: {
+    options = {
+        sequences: true,
+    }
+    input: {
+        var a = 2, b;
+        a *= (b, a = 4, 3);
+        console.log(a);
+    }
+    expect: {
+        var a = 2, b;
+        b, a *= (a = 4, 3),
+        console.log(a);
+    }
+    expect_stdout: "6"
+}
+
 for_sequences: {
     options = { sequences: true };
     input: {
@@ -230,6 +251,7 @@ negate_iife_for: {
         for (!function() {}(), i = 0; i < 5; i++) console.log(i);
         for (function() {}(); i < 5; i++) console.log(i);
     }
+    expect_stdout: true
 }
 
 iife: {
diff --git a/test/compress/transform.js b/test/compress/transform.js
index 7b616e40e92..1cc72c07705 100644
--- a/test/compress/transform.js
+++ b/test/compress/transform.js
@@ -13,6 +13,7 @@ booleans_evaluate: {
         console.log(!0, !0);
         console.log(!1, !1);
     }
+    expect_stdout: true
 }
 
 booleans_global_defs: {
@@ -29,6 +30,7 @@ booleans_global_defs: {
     expect: {
         console.log(!0);
     }
+    expect_stdout: true
 }
 
 condition_evaluate: {
diff --git a/test/run-tests.js b/test/run-tests.js
index 7f3256e0910..a3184d72c04 100755
--- a/test/run-tests.js
+++ b/test/run-tests.js
@@ -11,6 +11,17 @@ var vm = require("vm");
 var tests_dir = path.dirname(module.filename);
 var failures = 0;
 var failed_files = {};
+var same_stdout = ~process.version.lastIndexOf("v0.12.", 0) ? function(expected, actual) {
+    if (typeof expected != typeof actual) return false;
+    if (typeof expected != "string") {
+        if (expected.name != actual.name) return false;
+        expected = expected.message.slice(expected.message.lastIndexOf("\n") + 1);
+        actual = actual.message.slice(actual.message.lastIndexOf("\n") + 1);
+    }
+    return expected == actual;
+} : function(expected, actual) {
+    return typeof expected == typeof actual && expected.toString() == actual.toString();
+};
 
 run_compress_tests();
 if (failures) {
@@ -172,7 +183,7 @@ function run_compress_tests() {
                     }
                 }
                 if (test.expect_stdout) {
-                    var stdout = run_code(input_code);
+                    var stdout = run_code(make_code(input, output_options));
                     if (test.expect_stdout === true) {
                         test.expect_stdout = stdout;
                     }
@@ -336,7 +347,3 @@ function run_code(code) {
         process.stdout.write = original_write;
     }
 }
-
-function same_stdout(expected, actual) {
-    return typeof expected == typeof actual && expected.toString() == actual.toString();
-}