[Swig-user] using %extend to add a constructor doesn't call parent constructor

[Marco D. <mar...@gm...>]

Hello,

I'm getting this error message when wrapping a C++ library:

*** glibc detected *** /usr/bin/python2.5: free(): invalid pointer:
0xb7df6b40 ***

I use %extend to add a new constructor to a class, but for some
reasons I don't understand the parent constructor of this class is
never called.

I managed to reproduce the problem with this simple example:

class Foo
{
protected:
    Foo() {
            cout << "foo()" << endl;
    }

   ~Foo() {
            cout << "~foo()" << endl;
    }
};

class Bar : public Foo
{
    protected:
        Bar() {
            cout << "bar()" << endl;
        }
    public:
        ~Bar() {
            cout << "~bar()" << endl;
        }
};

the SWIG file:

%module test
%{
#define SWIG_FILE_WITH_INIT
#include <test.h>
%}

#include <iostream>

%include <test.h>

%extend Bar {
    Bar(int i) : Foo () {
        std::cout << "in extended bar constructor " << std::endl;
    }
};

and a Python test file:

#!/usr/bin/python2.5

import test as t

class Woo(t.Bar) :
    def __init__(self):
        super(Woo, self).__init__(2)


a = Woo()

Executing the python file outputs:

in extended bar constructor
~bar()
~foo()
*** glibc detected *** /usr/bin/python2.5: free(): invalid pointer:
0xb7cd2b40 ***

But I was expecting to see "foo()" at the beginning of the
output...anybody cares to explain me what I'm doing wrong please ?

Regards,
MD