Starting in build b73 of Mustang, javac would lock up after reporting an error when it encounters cyclic inheritance (example included below). In builds b72 and earlier, javac would report the cyclic inheritance error and then continue.

The following 4 JCK tests lock up due to this problem:
lang/CLSS/clss049/clss04902/clss04902.html
lang/CLSS/clss049/clss04905/clss04905.html
lang/CLSS/clss049/clss04906/clss04906.html
lang/ICLS/icls039/icls03913/icls03913.html


Example code:
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class clss04902a extends clss04902a { // compile-time error
}
public class clss04902 extends clss04902a {
  public static void main(String argv[])
  {
     System.exit(run(argv, System.out) + 95/*STATUS_TEMP*/);
  }
  public static int run(String argv[], PrintStream out) {
clss04902a x;
return 0/*STATUS_PASS*/;
  }
}
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