Fix this longstanding bug that luckily did not bite us yet: Use Class.prototype.foo$bailout.call(th…

sdk/lib/_internal/compiler/implementation/js_backend/namer.dart

Index: sdk/lib/_internal/compiler/implementation/js_backend/namer.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/js_backend/namer.dart	(revision 14946)
+++ sdk/lib/_internal/compiler/implementation/js_backend/namer.dart	(working copy)
@@ -30,12 +30,23 @@
   final Map<String, int> usedGlobals;
   final Map<String, LibraryElement> shortPrivateNameOwners;
 
+  /// A cache of names used for bailout methods. We make sure two

[karlklose, 2012/11/16 09:31:17]

I think you should /**...*/ here.

[ngeoffray, 2012/11/16 10:37:56]

Done.

+  /// bailout methods cannot have the same name because if one is

[karlklose, 2012/11/16 09:31:17]

I find "because if one is defined in a class that is a subclass of the other, we
would resolve to the wrong bailout method at runtime." hard to understand. How
about "because if the two bailout functions are in a class and its subclass, we
would call the wrong method at runtime."

[ngeoffray, 2012/11/16 10:37:56]

Done.

+  /// defined in a class that is a subclass of the other, we would
+  /// resolve to the wrong bailout method at runtime. To make it
+  /// simple, we don't keep track of inheritance and always avoid
+  /// similar names.
+  final Set<String> usedBailoutNames;
+  final Map<Element, String> bailoutNames;
+
   final Map<Constant, String> constantNames;
 
   Namer(this.compiler)
       : globals = new Map<Element, String>(),
         usedGlobals = new Map<String, int>(),
         shortPrivateNameOwners = new Map<String, LibraryElement>(),
+        bailoutNames = new Map<Element, String>(),
+        usedBailoutNames = new Set<String>(),
         constantNames = new Map<Constant, String>();
 
   final String CURRENT_ISOLATE = r'$';
@@ -237,7 +248,15 @@
   }
 
   String getBailoutName(Element element) {
-    return '${getName(element)}\$bailout';
+    String name = bailoutNames[element];
+    if (name != null) return name;
+    String candidate = '${getName(element)}\$bailout';
+    name = candidate;
+    int i = 0;
+    while (usedBailoutNames.contains(name)) name = '$candidate${i++}';

[karlklose, 2012/11/16 09:31:17]

Should we have a UniqueElementNameGenerator abstraction? ;-)

+    bailoutNames[element] = name;
+    usedBailoutNames.add(name);
+    return name;
   }
 
   /**