Hi All,
I am using a header file called vector.hh

#ifndef VECTOR_HH
#define VECTOR_HH
#include <assert.h>
template <class T>
class Vector { public:

typedef T value_type;
typedef T& reference;
typedef const T& const_reference;
typedef T* pointer;
typedef const T* const_pointer;

typedef int size_type;

typedef T* iterator;
typedef const T* const_iterator;

explicit Vector() : _l(0), _n(0), _capacity(0) { }
explicit Vector(size_type n, const T &e) : _l(0), _n(0),
_capacity(0) { resize(n, e); }
// template <class In> ...
Vector(const Vector<T> &);
~Vector();
private:

T *_l;
size_type _n;
size_type _capacity;

void *velt(size_type i) const { return (void*)&_l[i]; }
static void *velt(T* l, size_type i) { return (void*)&l[i]; }

};

template <>
class Vector<void*> { public:

typedef void* value_type;
typedef void*& reference;
typedef void* const& const_reference;
typedef void** pointer;
typedef void* const* const_pointer;

typedef int size_type;

typedef void** iterator;
typedef void* const* const_iterator;

explicit Vector() : _l(0), _n(0), _capacity(0) { }
explicit Vector(size_type n, void* e) : _l(0), _n(0), _capacity(0)
{}// resize(n, e); }
Vector(const Vector<void*> &);
~Vector();
private:

void **_l;
size_type _n;
size_type _capacity;

};
template <class T>
class Vector<T*>: private Vector<void*> {

typedef Vector<void*> Base;

public:

typedef T* value_type;
typedef T*& reference;
typedef T* const& const_reference;
typedef T** pointer;
typedef T* const* const_pointer;

typedef int size_type;

typedef T** iterator;
typedef T* const* const_iterator;

explicit Vector() : Base() { }
explicit Vector(size_type n, T* e) : Base(n, (void *)e) { }
Vector(const Vector<T *> &o) : Base(o) { }
~Vector() { }
};



and my main is


#include <vector.hh>
int main()
{
Vector<int *> x;

}





I am able to compile it but when I link I am getting the error


test.o: In function `Vector<int*>::~Vector()':
test.cpp.text._ZN6VectorIPiED1Ev[Vector<int*>::~Vector()]+0xd):
undefined reference to `Vector<void*>::~Vector()'
collect2: ld returned 1 exit status


I have been stuck with this for a long time but I have not found a
solution so far

Cheers

On Feb 8, 9:42 am, iceman <jegan...@gmail.com> wrote:
> Hi All,
> I am using a header file called vector.hh
>
> #ifndef VECTOR_HH
> #define VECTOR_HH
> #include <assert.h>
> template <class T>
> class Vector { public:
>
> typedef T value_type;
> typedef T& reference;
> typedef const T& const_reference;
> typedef T* pointer;
> typedef const T* const_pointer;
>
> typedef int size_type;
>
> typedef T* iterator;
> typedef const T* const_iterator;
>
> explicit Vector() : _l(0), _n(0), _capacity(0) { }
> explicit Vector(size_type n, const T &e) : _l(0), _n(0),
> _capacity(0) { resize(n, e); }
> // template <class In> ...
> Vector(const Vector<T> &);
> ~Vector();
> private:
>
> T *_l;
> size_type _n;
> size_type _capacity;
>
> void *velt(size_type i) const { return (void*)&_l[i]; }
> static void *velt(T* l, size_type i) { return (void*)&l[i]; }
>
> };
>
> template <>
> class Vector<void*> { public:
>
> typedef void* value_type;
> typedef void*& reference;
> typedef void* const& const_reference;
> typedef void** pointer;
> typedef void* const* const_pointer;
>
> typedef int size_type;
>
> typedef void** iterator;
> typedef void* const* const_iterator;
>
> explicit Vector() : _l(0), _n(0), _capacity(0) { }
> explicit Vector(size_type n, void* e) : _l(0), _n(0), _capacity(0)
> {}// resize(n, e); }
> Vector(const Vector<void*> &);
> ~Vector();
> private:
>
> void **_l;
> size_type _n;
> size_type _capacity;
>
> };
>
> template <class T>
> class Vector<T*>: private Vector<void*> {
>
> typedef Vector<void*> Base;
>
> public:
>
> typedef T* value_type;
> typedef T*& reference;
> typedef T* const& const_reference;
> typedef T** pointer;
> typedef T* const* const_pointer;
>
> typedef int size_type;
>
> typedef T** iterator;
> typedef T* const* const_iterator;
>
> explicit Vector() : Base() { }
> explicit Vector(size_type n, T* e) : Base(n, (void *)e) { }
> Vector(const Vector<T *> &o) : Base(o) { }
> ~Vector() { }
>
> };
>
> and my main is
>
> #include <vector.hh>
> int main()
> {
> Vector<int *> x;
>
> }
>
> I am able to compile it but when I link I am getting the error
>
> test.o: In function `Vector<int*>::~Vector()':
> test.cpp.text._ZN6VectorIPiED1Ev[Vector<int*>::~Vector()]+0xd):
> undefined reference to `Vector<void*>::~Vector()'
> collect2: ld returned 1 exit status
>
> I have been stuck with this for a long time but I have not found a
> solution so far
>
> Cheers

any particular reason for not using std::vector ?

Yuval

On 8 Feb, 08:42, iceman <jegan...@gmail.com> wrote:
> void **_l;
> size_type _n;
> size_type _capacity;

I suggest that you avoid using leading underscores in names.

> I am able to compile it but when I link I am getting the error
>
> test.o: In function `Vector<int*>::~Vector()':
> test.cpp.text._ZN6VectorIPiED1Ev[Vector<int*>::~Vector()]+0xd):
> undefined reference to `Vector<void*>::~Vector()'

As the linker states:
You're missing a definition for Vector<void*>::~Vector()

On Feb 8, 10:18 am, yuva...@gmail.com wrote:
> On Feb 8, 9:42 am, iceman <jegan...@gmail.com> wrote:
>
>
>
> > Hi All,
> > I am using a header file called vector.hh
>
> > #ifndef VECTOR_HH
> > #define VECTOR_HH
> > #include <assert.h>
> > template <class T>
> > class Vector { public:
>
> > typedef T value_type;
> > typedef T& reference;
> > typedef const T& const_reference;
> > typedef T* pointer;
> > typedef const T* const_pointer;
>
> > typedef int size_type;
>
> > typedef T* iterator;
> > typedef const T* const_iterator;
>
> > explicit Vector() : _l(0), _n(0), _capacity(0) { }
> > explicit Vector(size_type n, const T &e) : _l(0), _n(0),
> > _capacity(0) { resize(n, e); }
> > // template <class In> ...
> > Vector(const Vector<T> &);
> > ~Vector();
> > private:
>
> > T *_l;
> > size_type _n;
> > size_type _capacity;
>
> > void *velt(size_type i) const { return (void*)&_l[i]; }
> > static void *velt(T* l, size_type i) { return (void*)&l[i]; }
>
> > };
>
> > template <>
> > class Vector<void*> { public:
>
> > typedef void* value_type;
> > typedef void*& reference;
> > typedef void* const& const_reference;
> > typedef void** pointer;
> > typedef void* const* const_pointer;
>
> > typedef int size_type;
>
> > typedef void** iterator;
> > typedef void* const* const_iterator;
>
> > explicit Vector() : _l(0), _n(0), _capacity(0) { }
> > explicit Vector(size_type n, void* e) : _l(0), _n(0), _capacity(0)
> > {}// resize(n, e); }
> > Vector(const Vector<void*> &);
> > ~Vector();
> > private:
>
> > void **_l;
> > size_type _n;
> > size_type _capacity;
>
> > };
>
> > template <class T>
> > class Vector<T*>: private Vector<void*> {
>
> > typedef Vector<void*> Base;
>
> > public:
>
> > typedef T* value_type;
> > typedef T*& reference;
> > typedef T* const& const_reference;
> > typedef T** pointer;
> > typedef T* const* const_pointer;
>
> > typedef int size_type;
>
> > typedef T** iterator;
> > typedef T* const* const_iterator;
>
> > explicit Vector() : Base() { }
> > explicit Vector(size_type n, T* e) : Base(n, (void *)e) { }
> > Vector(const Vector<T *> &o) : Base(o) { }
> > ~Vector() { }
>
> > };
>
> > and my main is
>
> > #include <vector.hh>
> > int main()
> > {
> > Vector<int *> x;
>
> > }
>
> > I am able to compile it but when I link I am getting the error
>
> > test.o: In function `Vector<int*>::~Vector()':
> > test.cpp.text._ZN6VectorIPiED1Ev[Vector<int*>::~Vector()]+0xd):
> > undefined reference to `Vector<void*>::~Vector()'
> > collect2: ld returned 1 exit status
>
> > I have been stuck with this for a long time but I have not found a
> > solution so far
>
> > Cheers
>
> any particular reason for not using std::vector ?
>
> Yuval

as for your question, the error is because you haven't implemented a
destructor to Vector<void*>

On Feb 8, 7:20 pm, yuva...@gmail.com wrote:
> On Feb 8, 10:18 am, yuva...@gmail.com wrote:
>
>
>
> > On Feb 8, 9:42 am, iceman <jegan...@gmail.com> wrote:
>
> > > Hi All,
> > > I am using a header file called vector.hh
>
> > > #ifndef VECTOR_HH
> > > #define VECTOR_HH
> > > #include <assert.h>
> > > template <class T>
> > > class Vector { public:
>
> > > typedef T value_type;
> > > typedef T& reference;
> > > typedef const T& const_reference;
> > > typedef T* pointer;
> > > typedef const T* const_pointer;
>
> > > typedef int size_type;
>
> > > typedef T* iterator;
> > > typedef const T* const_iterator;
>
> > > explicit Vector() : _l(0), _n(0), _capacity(0) { }
> > > explicit Vector(size_type n, const T &e) : _l(0), _n(0),
> > > _capacity(0) { resize(n, e); }
> > > // template <class In> ...
> > > Vector(const Vector<T> &);
> > > ~Vector();
> > > private:
>
> > > T *_l;
> > > size_type _n;
> > > size_type _capacity;
>
> > > void *velt(size_type i) const { return (void*)&_l[i]; }
> > > static void *velt(T* l, size_type i) { return (void*)&l[i]; }
>
> > > };
>
> > > template <>
> > > class Vector<void*> { public:
>
> > > typedef void* value_type;
> > > typedef void*& reference;
> > > typedef void* const& const_reference;
> > > typedef void** pointer;
> > > typedef void* const* const_pointer;
>
> > > typedef int size_type;
>
> > > typedef void** iterator;
> > > typedef void* const* const_iterator;
>
> > > explicit Vector() : _l(0), _n(0), _capacity(0) { }
> > > explicit Vector(size_type n, void* e) : _l(0), _n(0), _capacity(0)
> > > {}// resize(n, e); }
> > > Vector(const Vector<void*> &);
> > > ~Vector();
> > > private:
>
> > > void **_l;
> > > size_type _n;
> > > size_type _capacity;
>
> > > };
>
> > > template <class T>
> > > class Vector<T*>: private Vector<void*> {
>
> > > typedef Vector<void*> Base;
>
> > > public:
>
> > > typedef T* value_type;
> > > typedef T*& reference;
> > > typedef T* const& const_reference;
> > > typedef T** pointer;
> > > typedef T* const* const_pointer;
>
> > > typedef int size_type;
>
> > > typedef T** iterator;
> > > typedef T* const* const_iterator;
>
> > > explicit Vector() : Base() { }
> > > explicit Vector(size_type n, T* e) : Base(n, (void *)e) { }
> > > Vector(const Vector<T *> &o) : Base(o) { }
> > > ~Vector() { }
>
> > > };
>
> > > and my main is
>
> > > #include <vector.hh>
> > > int main()
> > > {
> > > Vector<int *> x;
>
> > > }
>
> > > I am able to compile it but when I link I am getting the error
>
> > > test.o: In function `Vector<int*>::~Vector()':
> > > test.cpp.text._ZN6VectorIPiED1Ev[Vector<int*>::~Vector()]+0xd):
> > > undefined reference to `Vector<void*>::~Vector()'
> > > collect2: ld returned 1 exit status
>
> > > I have been stuck with this for a long time but I have not found a
> > > solution so far
>
> > > Cheers
>
> > any particular reason for not using std::vector ?
>
> > Yuval
>
> as for your question, the error is because you haven't implemented a
> destructor to Vector<void*>

But in each class I have implemented a destructor

yeah.I wanted to use this in a specific reference to click modular
router.Thats why I am using using vector.hh and not std::vector

On 8 Feb, 12:53, iceman <jegan...@gmail.com> wrote:
> On Feb 8, 7:20 pm, yuva...@gmail.com wrote:
>
> > as for your question, the error is because you haven't implemented a
> > destructor to Vector<void*>
>
> But in each class I have implemented a destructor

No you haven't. Look again:

template <class T>
class Vector {
~Vector(); // no dtor body
};

template <>
class Vector<void*> {
~Vector(); // **** no dtor body ****
};

template <class T>
class Vector<T*>: private Vector<void*> {
~Vector() { } // dtor body
};

The error message is telling you there's
no body for Vector<void*>::~Vector()