Name: dgC58589 Date: 01/16/98


Hello,

I ran into the following situation using JDK 1.1.3 on Solaris and
1.1.4 on Windows. I used a static initializer to allocate a data
structure. So far, so good, but I made an mistake in there which
caused an array overflow.

I didn't notice this at first, since the program continued to work. I
have been able to reduce the situation context to the following small
program:

public class bug {
  private static String str = "foo";
  private static int[] x;

  public static void main(String[] argv) {
    System.out.println(str);
  }

  static {
    System.out.println("in static");
    x = new int[10];
    x[-10]=4711;
    str="bar";
  }
}

This gives me the following output:

% java bug
in static
foo

The program works however, i.e. an error message is printed if I put
the main routine into a different class and just instantiate the class
`bug'.

Either the RuntimeException ArrayIndexOutOfBoundsException that should
have been raised is not thrown or not correctly handled. The former
would mean that I can access memory via illegal indices that shouldn't
be in my hands, but I guess that in fact the latter case applies.

BTW: VisualAge and kaffe didn't show this strange behaviour, i.e. they
both halted the program with an error message.

Yours
Markus
(Review ID: 23505)
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