libgcj/5696: natClass.cc run through superclasses of target if they exist while comparing variable types.

[toddastock at yahoo dot com]

>Number:         5696
>Category:       libgcj
>Synopsis:       natClass.cc run through superclasses of target if they exist while comparing variable types.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 14 20:16:02 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     
>Release:        3.1 20020214 (experimental)
>Organization:
>Environment:
System: Linux escher 2.4.9-21 #1 Thu Jan 17 14:16:30 EST 2002 i686 unknown
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ./configure --enable-threads=posix --prefix=/home/tstock/local --disable-shared --enable-languages=c++,java
>Description:
It's possible that you are comparing an Object (as source) against another builtin type like a Thread (as target).  In that case the Thread would have a superclass of Object which you have to search it's superclasses to validate that the variables are equal.
Shouldn't Thread even if it's a builtin type register true to the function 'isInterface()'??  Is this a bug generated by the compiler instead?
>How-To-Repeat:
import java.io.*;

public class TestException extends RuntimeException
  {
  }
import java.io.*;
import java.util.*;

public class Test
  {

  Object dummy = null;

  public static void main (String[] args)
    {

      Test t = new Test( );
      try
        {
          t.doit( new String("") );
        }
      catch( TestException e )
        {
        }
    }

  protected TestException dummyE()
    {
      return new TestException();
    }

  public void doit (String x) throws TestException
    {
      if( dummy != null )
        {
          throw dummyE();
        }
      
      if( dummy != null )
        {
          FileInputStream in = null;
          try
            {
              Properties props = new Properties();
              in = new FileInputStream(x);

              Enumeration enum = props.propertyNames();
              Vector v = new Vector();
            }
          catch( Exception e )
            {
              throw new TestException( );
            }
          finally
            {
              if( in != null )
                {
                  try
                    {
                      in.close();
                    }
                  catch( IOException ioex )
                    {
                    }
                }
            }
        }
      else
        {
          throw new TestException( );
        }
    }
  }
>Fix:
Possibly a non-recursive solution would be better??
Index: java/lang/natClass.cc
===================================================================
RCS file: /cvsroot/gcc/gcc/libjava/java/lang/natClass.cc,v
retrieving revision 1.50
diff -u -r1.50 natClass.cc
--- java/lang/natClass.cc	21 Dec 2001 19:47:50 -0000	1.50
+++ java/lang/natClass.cc	15 Feb 2002 03:50:28 -0000
@@ -962,11 +962,16 @@
 	}
       return false;
     }
   // Primitive TYPE classes are only assignable to themselves.
   if (__builtin_expect (target->isPrimitive(), false))
     return false;
     
+  if( target->getSuperclass( ) )
+    {
+      return _Jv_IsAssignableFrom( source, target->getSuperclass() );
+    }
+     
   if (target == &ObjectClass)
     {
       if (source->isPrimitive())
>Release-Note:
>Audit-Trail:
>Unformatted: