boost.python module extension generates SIGSEGV

Question

I'm trying to develop a python extension in C++. I'd be building the module with boost.python.

I've compiled boost1.69.0 with clang

Apple LLVM version 10.0.0 (clang-1000.11.45.5)
Target: x86_64-apple-darwin17.7.0
Thread model: posix

My class in C++ has member objects which are pointers to other classes, boost::unordered_map and structures with pointer members as well. The class also has templated functions, functions with signature static void *(void * ). In one of the header files I declare extern const objects which are also defined. The header looks like:

my_class.hpp:

#include <otherclass.hpp>
#include <boost/python.hpp>

class DP{

// Class objects and methods defined here
};

#ifdef __cplusplus
extern "C" {
#endif
    DP * newcase(const char *dir, int lenpath);
#ifdef __cplusplus
}
#endif

my_class.cpp:

DP * newcase(const char *dir, int lenpath){
    std::string path(dir);
    path = path.substr(0, lenpath);
    fs::path runDir(path);
    return new DP(runDir);
}

BOOST_PYTHON_MODULE(dp_py)
{
    using namespace boost::python;
    class_<DP>("DP", init<const char *>());

    def("newcase", &newcase, return_value_policy<manage_new_object>());
}

Compilation and linking is also working ok. Furthermore, I'm able to interface and use this library without any issues with another Fortran90 project. However, when I try to import the same in Python,

>>> from ctypes import *
>>> from os import environ, listdir
>>> import dp_py

I get a segmentation fault

Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)

Based on this answer I tried working with the python debugger. Towards the very end I see this output:

--Call--
> <frozen importlib._bootstrap_external>(919)create_module()
(Pdb) 
> <frozen importlib._bootstrap_external>(921)create_module()
(Pdb) 
> <frozen importlib._bootstrap_external>(922)create_module()
(Pdb) 
--Call--
> <frozen importlib._bootstrap>(211)_call_with_frames_removed()
(Pdb) 
> <frozen importlib._bootstrap>(219)_call_with_frames_removed()
(Pdb) 

Segmentation fault: 11

Whats being done in <frozen importlib._bootstrap>(219)_call_with_frames_removed() that results in a segmentation fault? How could I resolve this?

The python interpreter I use is:

Python 3.6.8 :: Anaconda custom (64-bit)

Answer 1

It turns out that including the global objects with extern const was the problem. Not including global objects now solves the error.