From 9e6b128374c62ee9f6238134fdc207ec9dc86284 Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Fri, 10 Mar 2017 03:15:21 +0800
Subject: [PATCH] fix catch variable reference in IE8 (#1587)

`AST_Scope.def_variable()` will overwrite `AST_Symbol.thedef`, so save a copy before calling.

fixes #1586
---
 lib/scope.js               |  3 ++-
 test/compress/screw-ie8.js | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/lib/scope.js b/lib/scope.js
index f23c8fe2..483503ee 100644
--- a/lib/scope.js
+++ b/lib/scope.js
@@ -212,9 +212,10 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
         self.walk(new TreeWalker(function(node, descend) {
             if (node instanceof AST_SymbolCatch) {
                 var name = node.name;
+                var refs = node.thedef.references;
                 var scope = node.thedef.scope.parent_scope;
                 var def = scope.find_variable(name) || self.globals.get(name) || scope.def_variable(node);
-                node.thedef.references.forEach(function(ref) {
+                refs.forEach(function(ref) {
                     ref.thedef = def;
                     ref.reference(options);
                 });
diff --git a/test/compress/screw-ie8.js b/test/compress/screw-ie8.js
index 36eb4d3a..4fbb95c8 100644
--- a/test/compress/screw-ie8.js
+++ b/test/compress/screw-ie8.js
@@ -182,3 +182,39 @@ reduce_vars: {
         }
     }
 }
+
+issue_1586_1: {
+    options = {
+        screw_ie8: false,
+    }
+    mangle = {
+        screw_ie8: false,
+    }
+    input: {
+        function f() {
+            try {
+            } catch (err) {
+                console.log(err.message);
+            }
+        }
+    }
+    expect_exact: "function f(){try{}catch(c){console.log(c.message)}}"
+}
+
+issue_1586_2: {
+    options = {
+        screw_ie8: true,
+    }
+    mangle = {
+        screw_ie8: true,
+    }
+    input: {
+        function f() {
+            try {
+            } catch (err) {
+                console.log(err.message);
+            }
+        }
+    }
+    expect_exact: "function f(){try{}catch(c){console.log(c.message)}}"
+}
-- 
2.34.1