Re: Compiling with jikes > 1.13

[Mark Wielaard]

Hi,

On Wed, 2002-02-06 at 15:40, Mark Wielaard wrote:
> 
> I am going to play a bit more with this to see if I can see were some of
> the other errors come from to better understand what libgcj is doing and
> wether I am not feeding you completely bogus data.

I changed the program a little bit to force loading all classes through
the same ClassLoader when possible. Now it actually seems to work. But a
lot of the VerifyErrors seem to be wrong.

For example the verifier doesn't like something like the following:

Method name:"compareTo" public Signature: 108=(java.lang.Object)int
Attribute "Code", length:56, max_stack:2, max_locals:2, code_length:24
  0: aload_1
  1: instanceof #1=<Class java.math.BigInteger>
  4: ifeq 16
  7: aload_0
  8: aload_1
  9: checkcast #1=<Class java.math.BigInteger>
 12: invokestatic #110=<Method java.math.BigInteger.compareTo
(java.math.BigInteger,java.math.BigInteger)int>
 15: ireturn
 16: new #111=<Class java.lang.ClassCastException>
 19: dup
 20: invokespecial #113=<Method java.lang.ClassCastException.<init>
()void>
 23: athrow

$ ./verifyclass java/math/BigInteger.class 
Verifying: java/math/BigInteger.class
java.lang.VerifyError: verification failed at PC 23 in
java.math.BigInteger:compareTo((Ljava.lang.Object;)I): incompatible type
on stack

But the bytecode looks good to me.

I attach the VerifyClass code so people can play with it.

I also tried compiling jikes from CVS but I am unable to compile
Classpath with it. Simple test programs work though. Needs some
debugging. Eric, is jikes from CVS 'stable'?

Cheers,

Mark

import java.io.*;

public class VerifyClass extends ClassLoader
{
    public static void main(String args[])
    {
      if (args.length == 1)
        {
          System.out.println("Verifying: " + args[0]);
          try
            {
              VerifyClass verifier = new VerifyClass();
              Class c = verifier.load(args[0]);
              verifier.resolveClass(c);
            }
          catch (Throwable t)
            {
              System.err.println(t);
            }
        }
      else
        System.out.println("argument must be a class file");
    }

    Class load(String classFile) throws IOException
    {
      InputStream is = new FileInputStream(classFile);
      ByteArrayOutputStream os = new ByteArrayOutputStream();
      byte[] buf = new byte[2048];

      int read = is.read(buf);
      while(read > 0)
        {
          os.write(buf, 0, read);
          read = is.read(buf);
        }

      byte[] data = os.toByteArray();
      return defineClass(data, 0, data.length);
    }

    protected Class loadClass(String name, boolean link)
      throws java.lang.ClassNotFoundException
    {
      if (!"java.lang.Object".equals(name))
        {
          try
            {
              Class c = load(name.replace('.','/') + ".class");

              if (link)
                resolveClass(c);

              return c;
            }
          catch(IOException ioe) { }
        }
      return super.loadClass(name, link);
    }
}