SWIG: Wrapping C++ for Perl using only a header and a shared library, can't locate loadable object error

The following seems to work on Ubuntu 16.04:

Files:

Animal.i:

%module Animal%{#include "Dog.h"#include "Crow.h"%}%include "Dog.h"%include "Crow.h"

Crow.h

class Crow {public:    Crow()  {        ncrows++;    }    virtual ~Crow() {        ncrows--;    }    static  int ncrows;};

Dog.h:

class Dog {public:    Dog()  {        ndogs++;    }    virtual ~Dog() {        ndogs--;    }    static  int ndogs;};

Crow.cpp:

#include "Crow.h"int Crow::ncrows = 0;

Dog.cpp:

#include "Dog.h"int Dog::ndogs = 0;

test.pl:

use strict;use warnings;use Animal;print "Creating a Crow:\n";my $c = Animal::Crow->new();print "    Created crow $c\n";$c->DESTROY();print "Creating a Dog:\n";my $d = Animal::Dog->new();print "    Created dog $d\n";$d->DESTROY();

Compilation:

swig -perl -c++ Animal.ig++ -fPIC -c Crow.cppg++ -fPIC -c Dog.cppg++ -shared Crow.o Dog.o -o libmylib.sog++ -fPIC -c Animal_wrap.cxx -I/usr/lib/x86_64-linux-gnu/perl/5.22/COREg++ -shared -L. Animal_wrap.o -lmylib -o Animal.so

Running test script:

$ LD_LIBRARY_PATH=. perl test.pl Creating a Crow:    Created crow Animal::Crow=HASH(0x10c2eb0)Creating a Dog:    Created dog Animal::Dog=HASH(0x10c2f88)