We (and others) noticed that some stuff wouldn’t compile anymore under the new cs4 flash authoring tool. The compiler complained mostly with messages like ‘1020: Method marked override must override another method.’
Thanks to a post on this blog we found the following bug on bugs.adobe.com. As you can see, it turns out the compiler is wrong. It cannot handle internal classes (and our tests suggest this behaviour is erratic). This breaks backwards compatibility in a major way, but it seems Adobe didn’t catch this in their testsuites.
We started refactoring immediately by removing the internal classes from some of the classes that used them and at the moment everything is back to normal again. All tests passed. This is on top of an earlier refactoring where we tried to fix the issue by changing some stuff on interfaces and by introducing an abstract List type in the inheritance chain for LinkedList and ArrayList.
We’ll put up the new stuff somewhere this week.
We have put the new source code in the repository.