[vmkit-commits] About j3-64bit crush

[Minas Abrahamyan]

Hi Nicolas,

I've recently made existent traces of debug logging to work and added
needed new PRINT_DEBUG-s,
to see why j3 run on HelloWorld crushes.
It's very beautufil to have such logs, it pretty visualizes the VMkit
work. Also it is useful tool for extensive debugging.

Crush occurs within j3::Jnjvm::loadBootstrap():
when running Class::initialiseClass() of last macro
LOAD_CLASS(upcalls->SystemClass)
but before initializing vm->appClassLoader; which would be done just
by the next call to loadAppClassLoader()
in Jnjvm.cpp.

<<<
native compile java/lang/VMRuntime.nativeLoad()
--> end of native compile java/lang/VMRuntime.nativeLoad()
[Switching to Thread 0x1200ff700 (LWP 11395)]

Breakpoint 1, Java_java_lang_VMRuntime_nativeLoad (str=0x7ffff020b750,
javaLoader=0x0)
    at ClasspathVMRuntime.inc:113
>>>
...many debugging results skipped...

Fruitful was comparison with 32-bit version - as it's working.

And I've found that Problem is FindClass does not load class
"gnu/classpath/Pointer64" and returns 0,
while the 32-bit counterpart does find and load corresponding
"gnu/classpath/Pointer32";

This is result of
UserClass* currentClass = th->getCallingClassLevel(0);
in FindClass returns 0;
<= JavaThread::getCallingClassLevel - returns 0, since all
'MethodInfo's in stack have value of MethodType==-1

While 32-bit version finds right value from stack, right value here is
'MethodInfo's with MethodType==1
//why not enums?

So much for now. Something wrongly initializes type values of methods

Regards,
Minas