gcj crashes now with small example

[Fabian Sturm <sturmf@xxxxxxxxxxxxxxxxxxxxxxxxx>]

hi!

I already posted a problem running vCreateJavaVM(NULL);
It seems it can't be run inside a thread??

I now produced a very small example showing the crash.
The backtrace was:

[Switching to Thread 16386 (LWP 18107)]
0x40559247 in GC_push_all_eager () from /usr/lib/libgcj.so.4
(gdb) bt
#0  0x40559247 in GC_push_all_eager () from /usr/lib/libgcj.so.4
#1  0x405592c2 in GC_push_all_stack () from /usr/lib/libgcj.so.4
#2  0x40555776 in GC_push_all_stacks () from /usr/lib/libgcj.so.4
#3  0x4055bfd7 in GC_default_push_other_roots () from /usr/lib/libgcj.so.4
#4  0x4055a4a2 in GC_push_roots () from /usr/lib/libgcj.so.4
#5  0x40558056 in GC_mark_some () from /usr/lib/libgcj.so.4
#6  0x4054fbbe in GC_stopped_mark () from /usr/lib/libgcj.so.4
#7  0x4054f8b5 in GC_try_to_collect_inner () from /usr/lib/libgcj.so.4
#8  0x4055ad6d in GC_init_inner () from /usr/lib/libgcj.so.4
#9  0x4055aa0e in GC_init () from /usr/lib/libgcj.so.4
#10 0x40553ae9 in GC_init_gcj_malloc () from /usr/lib/libgcj.so.4
#11 0x4054d1e5 in _Jv_InitGC() () from /usr/lib/libgcj.so.4
#12 0x40361baa in _Jv_CreateJavaVM(void*) () from /usr/lib/libgcj.so.4
#13 0x08048df3 in JvCreateJavaVM (vm_args=0x0) at cni.h:125
#14 0x08048bf9 in testclass::testThread() (this=0x8049c98) at crashme.cpp:38
#15 0x08048bd5 in testclass::testThreadStartRoutine(void*) (data=0x8049c98) at crashme.cpp:27
#16 0x40037cca in omni_thread_wrapper () from /usr/lib/libomnithread.so.3
#17 0x408dcf60 in pthread_start_thread () from /lib/i686/libpthread.so.0
#18 0x408dd0fe in pthread_start_thread_event () from /lib/i686/libpthread.so.0
#19 0x40a17327 in clone () from /lib/i686/libc.so.6

Hope this helps to find the problem.

The used software was:
  gcc (GCC) 3.3.1 (SuSE Linux)
  libomnithread.so.3 from omniORB-4.0.2-3


Hope this helps to finally find the problem!

Thanks Fabian

#include <omnithread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <iostream>

#include <gcj/cni.h>
#include <java/lang/Throwable.h>


class testclass {
	public:	
		testclass();
		void run();
		static void * testThreadStartRoutine(void *data);
		void testThread();
};


testclass::testclass() {
}

void * testclass::testThreadStartRoutine(void * data)
{
	std::cout << "thread started" << std::endl;
	testclass * tc=(testclass*) data;
	tc->testThread();
	return 0;
}

void testclass::testThread() {
	try
      	{
        	//java VM already initialized?
        	static bool javaVM = false;
        	if (!javaVM)
          	{
            		JvCreateJavaVM(NULL);
            		javaVM = true;
          	}

        	// attach current thread to java. should have no sideeffects if already attached
        	JvAttachCurrentThread(NULL, NULL);

        	// create space-manager, this would be the call to create a method creating a java object
        	// m_jLayoutArea = SpaceManagerUtils::toRectangle2i(m_layoutArea);

      	}
    	catch (java::lang::Throwable *t)
      	{
        	throw t;
      	}


	while (1) {
		std::cout << "in thread"<< std::endl;
	}
}

void testclass::run() {
	(new omni_thread(&testThreadStartRoutine, this))->start();
}



int main(int argc, char **argv)
{
	testclass *t = new testclass();

/*****
 * Here is the error, if done like this it crashes
 * if you remove t->run() and replace it with t->testThread() it starts to work!
 */
	t->run();
	//t->testThread();


	while (1) {
		sleep(10);
	}

}

LIBS = -L/usr/lib -lomnithread


all: crashme

crashme: crashme.o $(EXTERNAL_OBJECTS) 
	gcj $(LIBS) -o $@ $^

%.o: %.cpp
	g++ $(INCLUDES) -c -g -o $(OBJDIR)$@ $^

clean: 
	rm crashme crashme.o