fix corner case in ie8 (#3207)

fixes #3206

Author: alexlamsl

lib/compress.js

@@ -336,13 +336,10 @@ merge(Compressor.prototype, {
             def.chained = false;
             def.direct_access = false;
             def.escaped = false;
-            if (def.scope.pinned()) {
-                def.fixed = false;
-            } else if (!compressor.exposed(def)) {
-                def.fixed = def.init;
-            } else {
-                def.fixed = false;
-            }
+            def.fixed = !def.scope.pinned()
+                && !compressor.exposed(def)
+                && !(def.init instanceof AST_Function && def.init !== def.scope)
+                && def.init;
             if (def.fixed instanceof AST_Defun && !all(def.references, function(ref) {
                 var scope = ref.scope;
                 do {
@@ -3444,6 +3441,7 @@ merge(Compressor.prototype, {
             if (scope !== self) return;
             if (node instanceof AST_Function
                 && node.name
+                && !compressor.option("ie8")
                 && !compressor.option("keep_fnames")) {
                 var def = node.name.definition();
                 // any declarations with same name will overshadow
@@ -3927,8 +3925,39 @@ merge(Compressor.prototype, {
         }
 
         def(AST_Node, return_this);
-        def(AST_Constant, return_null);
-        def(AST_This, return_null);
+        def(AST_Accessor, return_null);
+        def(AST_Array, function(compressor, first_in_statement) {
+            var values = trim(this.elements, compressor, first_in_statement);
+            return values && make_sequence(this, values);
+        });
+        def(AST_Assign, function(compressor) {
+            var left = this.left;
+            if (left.has_side_effects(compressor)
+                || compressor.has_directive("use strict")
+                    && left instanceof AST_PropAccess
+                    && left.expression.is_constant()) {
+                return this;
+            }
+            this.write_only = true;
+            if (root_expr(left).is_constant_expression(compressor.find_parent(AST_Scope))) {
+                return this.right.drop_side_effect_free(compressor);
+            }
+            return this;
+        });
+        def(AST_Binary, function(compressor, first_in_statement) {
+            var right = this.right.drop_side_effect_free(compressor);
+            if (!right) return this.left.drop_side_effect_free(compressor, first_in_statement);
+            if (lazy_op[this.operator]) {
+                if (right === this.right) return this;
+                var node = this.clone();
+                node.right = right;
+                return node;
+            } else {
+                var left = this.left.drop_side_effect_free(compressor, first_in_statement);
+                if (!left) return this.right.drop_side_effect_free(compressor, first_in_statement);
+                return make_sequence(this, [ left, right ]);
+            }
+        });
         def(AST_Call, function(compressor, first_in_statement) {
             if (!this.is_expr_pure(compressor)) {
                 if (this.expression.is_call_pure(compressor)) {
@@ -3959,36 +3988,6 @@ merge(Compressor.prototype, {
             var args = trim(this.args, compressor, first_in_statement);
             return args && make_sequence(this, args);
         });
-        def(AST_Accessor, return_null);
-        def(AST_Function, return_null);
-        def(AST_Binary, function(compressor, first_in_statement) {
-            var right = this.right.drop_side_effect_free(compressor);
-            if (!right) return this.left.drop_side_effect_free(compressor, first_in_statement);
-            if (lazy_op[this.operator]) {
-                if (right === this.right) return this;
-                var node = this.clone();
-                node.right = right;
-                return node;
-            } else {
-                var left = this.left.drop_side_effect_free(compressor, first_in_statement);
-                if (!left) return this.right.drop_side_effect_free(compressor, first_in_statement);
-                return make_sequence(this, [ left, right ]);
-            }
-        });
-        def(AST_Assign, function(compressor) {
-            var left = this.left;
-            if (left.has_side_effects(compressor)
-                || compressor.has_directive("use strict")
-                    && left instanceof AST_PropAccess
-                    && left.expression.is_constant()) {
-                return this;
-            }
-            this.write_only = true;
-            if (root_expr(left).is_constant_expression(compressor.find_parent(AST_Scope))) {
-                return this.right.drop_side_effect_free(compressor);
-            }
-            return this;
-        });
         def(AST_Conditional, function(compressor) {
             var consequent = this.consequent.drop_side_effect_free(compressor);
             var alternative = this.alternative.drop_side_effect_free(compressor);
@@ -4008,6 +4007,14 @@ merge(Compressor.prototype, {
             node.alternative = alternative;
             return node;
         });
+        def(AST_Constant, return_null);
+        def(AST_Dot, function(compressor, first_in_statement) {
+            if (this.expression.may_throw_on_access(compressor)) return this;
+            return this.expression.drop_side_effect_free(compressor, first_in_statement);
+        });
+        def(AST_Function, function(compressor) {
+            return this.name && compressor.option("ie8") ? this : null;
+        });
         def(AST_Unary, function(compressor, first_in_statement) {
             if (unary_side_effects[this.operator]) {
                 this.write_only = !this.expression.has_side_effects(compressor);
@@ -4021,23 +4028,20 @@ merge(Compressor.prototype, {
             }
             return expression;
         });
-        def(AST_SymbolRef, function(compressor) {
-            return this.is_declared(compressor) ? null : this;
-        });
         def(AST_Object, function(compressor, first_in_statement) {
             var values = trim(this.properties, compressor, first_in_statement);
             return values && make_sequence(this, values);
         });
         def(AST_ObjectProperty, function(compressor, first_in_statement) {
             return this.value.drop_side_effect_free(compressor, first_in_statement);
         });
-        def(AST_Array, function(compressor, first_in_statement) {
-            var values = trim(this.elements, compressor, first_in_statement);
-            return values && make_sequence(this, values);
-        });
-        def(AST_Dot, function(compressor, first_in_statement) {
-            if (this.expression.may_throw_on_access(compressor)) return this;
-            return this.expression.drop_side_effect_free(compressor, first_in_statement);
+        def(AST_Sequence, function(compressor) {
+            var last = this.tail_node();
+            var expr = last.drop_side_effect_free(compressor);
+            if (expr === last) return this;
+            var expressions = this.expressions.slice(0, -1);
+            if (expr) expressions.push(expr);
+            return make_sequence(this, expressions);
         });
         def(AST_Sub, function(compressor, first_in_statement) {
             if (this.expression.may_throw_on_access(compressor)) return this;
@@ -4047,14 +4051,10 @@ merge(Compressor.prototype, {
             if (!property) return expression;
             return make_sequence(this, [ expression, property ]);
         });
-        def(AST_Sequence, function(compressor) {
-            var last = this.tail_node();
-            var expr = last.drop_side_effect_free(compressor);
-            if (expr === last) return this;
-            var expressions = this.expressions.slice(0, -1);
-            if (expr) expressions.push(expr);
-            return make_sequence(this, expressions);
+        def(AST_SymbolRef, function(compressor) {
+            return this.is_declared(compressor) ? null : this;
         });
+        def(AST_This, return_null);
     })(function(node, func) {
         node.DEFMETHOD("drop_side_effect_free", func);
     });

test/compress/ie8.js

@@ -666,3 +666,48 @@ issue_3197_2_ie8: {
     }
     expect_stdout: "true"
 }
+
+issue_3206_1: {
+    options = {
+        evaluate: true,
+        ie8: false,
+        reduce_vars: true,
+        typeofs: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var foo = function bar() {};
+            return "function" == typeof bar;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            return "function" == typeof bar;
+        }());
+    }
+    expect_stdout: "false"
+}
+
+issue_3206_2: {
+    options = {
+        evaluate: true,
+        ie8: true,
+        reduce_vars: true,
+        typeofs: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var foo = function bar() {};
+            return "function" == typeof bar;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function bar() {});
+            return "function" == typeof bar;
+        }());
+    }
+    expect_stdout: "false"
+}