Message1048

sgala@marlow ~ $ rlwrap jython
Jython 2.2a1 on java1.5.0 (JIT: j9jit23)
Type "copyright", "credits" or "license" for more
information.
>>> ('',''.join([i for i in ['','']]))
Traceback (innermost last):
  (no code object) at line 0
java.lang.VerifyError: stack shape inconsistent (class:
org/python/pycode/_pyx6 method:
f$0(Lorg/python/core/PyFrame;)Lorg/python/core/PyObject;)
at pc: 138
        at java.lang.J9VMInternals.verifyImpl(Native
Method)
        at
java.lang.J9VMInternals.verify(J9VMInternals.java:42)
        at
java.lang.ClassLoader.resolveClass(ClassLoader.java:566)
        at
org.python.core.BytecodeLoader2.loadClassFromBytes(Unknown
Source)
        at
org.python.core.BytecodeLoader.makeClass(Unknown Source)
        at
org.python.core.BytecodeLoader.makeCode(Unknown Source)
        at org.python.core.Py.compile_flags(Unknown Source)
        at
org.python.core.Py.compile_command_flags(Unknown Source)
        at
org.python.util.InteractiveInterpreter.runsource(Unknown
Source)
        at
org.python.util.InteractiveInterpreter.runsource(Unknown
Source)
        at
org.python.util.InteractiveConsole.push(Unknown Source)
        at
org.python.util.InteractiveConsole.interact(Unknown Source)
        at org.python.util.jython.main(Unknown Source)

java.lang.VerifyError: java.lang.VerifyError: stack
shape inconsistent (class: org/python/pycode/_pyx6
method:
f$0(Lorg/python/core/PyFrame;)Lorg/python/core/PyObject;)
at pc: 138

This is using jython 2.2a1 with IBM jdk 5.0 beta, and
disappears when running with -noverify.
It wasn't happening under IBM jdk 1.4.2 or other VMs
before, but I can't test it with other 5 VMs, so I'm
not sure if it is a bytecode generation issue that has
been always there, but is uncovered by new verification
rules, or else a problem in IBM jdk