Embedding python into shared library crash on AIX

[damahay123]

BPO	6742
Nosy	@loewis

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2009-08-20.13:32:01.217>
labels = ['interpreter-core', 'type-crash']
title = 'Embedding python into shared library crash on AIX'
updated_at = <Date 2014-03-23.03:12:47.956>
user = 'https://bugs.python.org/damahay123'

bugs.python.org fields:

activity = <Date 2014-03-23.03:12:47.956>
actor = 'BreamoreBoy'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core']
creation = <Date 2009-08-20.13:32:01.217>
creator = 'damahay123'
dependencies = []
files = []
hgrepos = []
issue_num = 6742
keywords = []
message_count = 5.0
messages = ['91773', '91789', '116025', '192851', '214541']
nosy_count = 4.0
nosy_names = ['loewis', 'sable', 'damahay123', 'BreamoreBoy']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'languishing'
superseder = None
type = 'crash'
url = 'https://bugs.python.org/issue6742'
versions = ['Python 2.6']

[damahay123]

Hi there,
I'm trying to embedding my python code into a .so on AIX and load it
with my main application. Since there is no libpython2.6.so available on
AIX, I have to link my .so with libpython2.6.a. I have to make some
twist to make it compile. And so far so good until I run my main. My
embedding python .so give me error like the following
Fatal Python error: Interpreter not initialized (version mismatch?)
I check the initialization status by calling Py_IsInitialized and it
said yes. So I'm wondering if this embedding python into .so ever work
on AIX.
I have no problem to do the same thing on linux, solaris since python
has libpython2.6.so on both system. But our system needs the supoort on
AIX. My embedding python is very simple like the following

#include <Python.h>
#include <iostream>

extern "C"
void allocate()
{
    std::cout << " am i ok = " << Py_IsInitialized() << std::endl;
    
    Py_InitializeEx(0);
    std::cout << " am i ok 1 = " << Py_IsInitialized() << std::endl;
    
    PyRun_SimpleString("from time import time, datetime, ctime\n"
                       "print 'Today is',ctime(time())\n");
    Py_Finalize();
}

my main application is also very simple
#include <iostream>
#include <iomanip>
#include <dlfcn.h>
//#include <link.h>
#include <Python.h>

typedef  void (*ALLOCATE)();

int main (int argc, char ** argv)
{
    // parse params to load shared object
    if (argc < 2)
    {
	std::cerr << "Usage: " << argv[0] << " sharedObject(s)" << std::endl;
	return 0;
    }

    //    Py_Initialize();
    
    for (int i = 1; i < argc; ++i)
    {
	void * handle = ::dlopen(argv[i], RTLD_LAZY);
	if (!handle)
	{
	    std::cerr << dlerror() << argv[i] << std::endl;
	
	    return 0;
	}
	
	// Use that handle to locate the symbol.  The symbol must be 
	// demangled so it has to be compiled with extern "C".
	ALLOCATE dlmAllocate = (ALLOCATE) ::dlsym(handle, "allocate");
	if (!dlmAllocate)
	{
	    std::cerr << dlerror() << std::endl;
	    return 0;
	}
    
	dlmAllocate();
    }


    return 0;
}

here is my makefile

CXX := g++

default: DLOpenTest mypython.so

DLOpenTest: DLOpen.C
$(CXX) -o DLOpenTest DLOpen.C -ldl
-Wl,-bE:/mnts/cdstools/Python-2.6.2/aix-ppc-5.3/lib/python2.6/config/python.exp
-lld -I/mnts/cdstools/Python-2.6.2/aix-ppc-5.3/include/python2.6
-L/mnts/cdstools/Python-2.6.2/aix-ppc-5.3/lib/ -lpython2.6 -lpthread

mypython.so: mypython.C
$(CXX) -shared -nostartfiles
-I/mnts/cdstools/Python-2.6.2/aix-ppc-5.3/include/python2.6
-L/mnts/cdstools/Python-2.6.2/aix-ppc-5.3/lib/ -lpython2.6 -lpthread -o
mypython.so mypython.C

clean:
rm *.o DLOpenTest mypython.so

Can someone help me out? Or has anyone even tried same thing on AIX?

NOTE, the issue is not like bpo-4434 or 1332869. Please don't reply
this issue with those two number. I've seen them already. It's not helpful

Thanks a log

[loewis]

If you get differing results from Py_IsInitialized, my guess is that you
managed to link two different copies of the Python VM into your
application, each with its own set of global variables.

An AIX expert would be required to diagnose this in more detail;
unfortunately, we are not aware of any such expert.

[sable]

You may want to take a look at bpo-941346 in order to compile libpython2.6.so on AIX.

I also embed python in my AIX application, and I had no problem once python was compiled as share thanks to the patch provided in the other issue.

[sable]

This issue has been fixed as part of bpo-941346 and should be closed in my opinion.

[BreamoreBoy]

msg192851 states that this should be closed. If somebody agrees with that statement would they please do the honours.