Debugging JNI shared libraries

From: Dave Neary (real.addressinthesig_at_thisoneis.invalid)
Date: 10/07/03 

Date: 07 Oct 2003 09:49:44 GMT

Hi all,

I have been trying to get some JNI code working on Win32 (the code is
libxmlj from the classpathx project). Compiles fine on Linux, and
compiles OK on Win32 when I have teh requisite stuff installed and I'm
using mingw, and I make a few changes (I really should learn how to use
Visual Studio).

I load my DLL/so via System.loadLibrary, and on Linux things go off
without a hitch. On Win32, I get an access violation, attempt to
reference object at address 0x00000... - looks like a null pointer
dereference to me. So I compiled the Linux .so with efence (hoping to
provoke a core dump in an environment that I know pretty well, and
diagnose the problem), but I have not been able to replicate the problem
at all.

Which brings me to my question. How can I debug this kind of thing on
Win32? Is there a way to load a DLL in a debugger, and (say) when
DllMain gets called, attach to the dll? How can I go about localising
the problem? The best option available to me at the moment seems to be a
bunch of printfs, which will perhaps help localise things. It would be
nice to get a core dump/stack trace though.

So - any Win32 people with good debugging tips for debugging shared
objects?

Thanks for your help,
Cheers,
Dave. 

-- 
                David Neary,
        E-Mail: bolsh at gimp dot org
   Work e-mail: d dot neary at phenix dot fr
CV: http://www.redbrick.dcu.ie/~bolsh/CV/CV.html

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