undefined reference(compile error), plz help

[eric]

Dear advance c++ programers:

I tried to type in/test your code in chapter 2 of c++ primer (3rd
ed)
page 45, 46, 49
IntArray.h
IntArrayRC.h
(and add IntArray.cpp myself) /* they are all simple */

the following is my code copied from your book
----------------------------------------------
#include <iostream>
#include "IntArray.h"
#include "IntArrayRC.h"

using namespace std;

void swap(IntArray&, int, int);

int main() {
int array[ 4 ] = { 0, 1, 2, 3 };
IntArray ia1( array, 4 );
IntArrayRC ia2( array, 4 );

// error: off-by-one: should be size - 1
// not caught by IntArray object
cout << "swap() with IntArray ia1\n";
swap( ia1, 1, ia1.size() );

// ok: caught by IntArrayRC object
cout << "swap() with IntArrayRC ia2\n";
swap( ia2, 1, ia2.size() );

return 0;
}

void swap( IntArray &ia, int i, int j )
{
int tmp = ia[ i ];
ia[ i ] = ia[ j ];
ia[ j ] = tmp;
}
----------------------------------------------------
#ifndef IntArray_H
#define IntArray_H

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray &rhs );

// virtual destructor!
virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
virtual int& operator[](int index) { return ia[index]; }
// int size() const; // #1
virtual void sort(); // #4

virtual int min() const; // #3a
virtual int max() const; // #3b

// if the value is found within the aray,
// return the index of its first occurrence
// otherwise, return -1

virtual int find ( int value ) const; // #3c

protected:
// the private implementation
static const int DefaultArraySize = 12;
void init( int sz, int *array );

int _size;
int *ia;
};

#endif
----------------------------------------------
#ifndef IntArrayRC_H
#define IntArrayRC_H

#include "IntArray.h"

class IntArrayRC : public IntArray {
public:
IntArrayRC( int sz = DefaultArraySize );
IntArrayRC( int *array, int array_size );
IntArrayRC( const IntArrayRC &rhs );
virtual int& operator[]( int );

private:
void check_range( int );
};

#endif
-------------------------------------------------
// IntArray.cpp

#include "IntArray.h"

IntArray::IntArray(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}
------------------------------------------------------------
but my compile result( errors) is
--
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp pg49.cpp
/tmp/ccOnEojJ.o: In function `IntArray::IntArray(int*, int)':
IntArray.cpp.text+0x8): undefined reference to `vtable for IntArray'
/tmp/ccdxV8oM.o: In function `main':
pg49.cpp.text+0x5e): undefined reference to
`IntArrayRC::IntArrayRC(int*, int)'
/tmp/ccdxV8oM.o: In function `IntArray::~IntArray()':
pg49.cpp.text._ZN8IntArrayD2Ev[_ZN8IntArrayD5Ev]+0xb): undefined
reference to `vtable for IntArray'
/tmp/ccdxV8oM.o: In function `IntArrayRC::~IntArrayRC()':
pg49.cpp.text._ZN10IntArrayRCD2Ev[_ZN10IntArrayRCD5Ev]+0xb):
undefined reference to `vtable for IntArrayRC'
collect2: ld returned 1 exit status
eric@eric-laptop:~/CppPrimer3$
---------
you can see, in my IntArray.cpp, I already defined IntArray
constructor, but why I still got
In function IntArray::IntArray(int*, int) undefined reference to
'vtable for IntArray'
plz help, thank a lot in advance, Eric

 

[eric]

class IntArray {
public:
   // equality and inequality operations:  #2b
   explicit IntArray( int size = DefaultArraySize );
   IntArray( int *array, int array_size );
   IntArray( const IntArray &rhs );

   // virtual destructor!
   virtual ~IntArray() { delete [] ia; }

   // equality and inequality operations:
   bool operator==( const IntArray& ) const;
   bool operator!=( const IntArray& ) const;

   // assignment operator: #2a
   IntArray& operator=( const IntArray& );
   int size() const { return _size; }

// we've removed the check on the index...
   virtual int& operator[](int index) { return ia[index]; }
   // int size() const;  // #1
   virtual void sort();       // #4
[...]

but my compile result( errors) is

With g++ this typically means you have not provided definition of the
first non-inline virtual function in this class. As far as I can see,
this would be IntArray::Sort(). Provide a definition of this function
(and all other non-defined virtual functions) in the relevant .cpp file.

In C++ one can in principle leave out definitions for functions which are
not used, but all virtual functions are effectively "used" for populating
the vtable entries, so they must be all present in the program.

hth
Paavo

/
***********************************************************************************************/

Thanks Paavo and Brian your reply on this undefined reference

now I delete more variables, functions in my IntArray.h and add
IntArrayRC.cpp(and IntArray.cpp)
/
***********************************************************************************************/
#ifndef IntArray_H
#define IntArray_H

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray &rhs );

// virtual destructor!
// virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
/* virtual */ int& operator[](int index) { return ia[index]; }
// int size() const; // #1
// virtual void sort(); // #4

//virtual int min() const; // #3a
//virtual int max() const; // #3b

// if the value is found within the aray,
// return the index of its first occurrence
// otherwise, return -1

/*virtual*/ int find ( int value ) const; // #3c

protected:
// the private implementation
static const int DefaultArraySize = 12;
void init( int sz, int *array );

int _size;
int *ia;
};

#endif
/*--------------------*/
#ifndef IntArrayRC_H
#define IntArrayRC_H

#include "IntArray.h"

class IntArrayRC : public IntArray {
public:
IntArrayRC( int _size = DefaultArraySize );
IntArrayRC( int *array, int array_size );
IntArrayRC( const IntArrayRC &rhs );
/* virtual*/ int& operator[]( int );

private:
void check_range( int );
};

#endif
/*----------------------------*/
// IntArrayRC.cpp

#include "IntArrayRC.h"

IntArrayRC::IntArrayRC(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}
/*-------------------------------------------------------*/
// IntArray.cpp

#include "IntArray.h"

IntArray::IntArray(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}

/*-------------------------------------------------------*/
/* my pg49.cpp and IntArray.cpp didn't change */
/*--------- ----------*/
/* I tried to make everything simple, just hope to make it run, but
it still not work, and I don't see my IntArrayRC.cpp or pg49.cpp
reference
* IntArray::IntArray(int)' at all. how come compiler complain
that?
*/
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
/tmp/ccFlMagZ.o: In function `IntArrayRC::IntArrayRC(int*, int)':
IntArrayRC.cpp.text+0x15): undefined reference to
`IntArray::IntArray(int)'
collect2: ld returned 1 exit status
eric@eric-laptop:~/CppPrimer3$


looking to see any advancer's help again, and
Thanks a lot in advance,
Eric

 

[Victor Bazarov]

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray&rhs );

// virtual destructor!
virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
virtual int& operator[](int index) { return ia[index]; }
// int size() const; // #1
virtual void sort(); // #4
[...]

but my compile result( errors) is

With g++ this typically means you have not provided definition of the
first non-inline virtual function in this class. As far as I can see,
this would be IntArray::Sort(). Provide a definition of this function
(and all other non-defined virtual functions) in the relevant .cpp file.

In C++ one can in principle leave out definitions for functions which are
not used, but all virtual functions are effectively "used" for populating
the vtable entries, so they must be all present in the program.

hth
Paavo

/
***********************************************************************************************/

Thanks Paavo and Brian your reply on this undefined reference

now I delete more variables, functions in my IntArray.h and add
IntArrayRC.cpp(and IntArray.cpp)
/
***********************************************************************************************/
#ifndef IntArray_H
#define IntArray_H

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray&rhs );

// virtual destructor!
// virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
/* virtual */ int& operator[](int index) { return ia[index]; }
// int size() const; // #1
// virtual void sort(); // #4

//virtual int min() const; // #3a
//virtual int max() const; // #3b

// if the value is found within the aray,
// return the index of its first occurrence
// otherwise, return -1

/*virtual*/ int find ( int value ) const; // #3c

protected:
// the private implementation
static const int DefaultArraySize = 12;
void init( int sz, int *array );

int _size;
int *ia;
};

#endif
/*--------------------*/
#ifndef IntArrayRC_H
#define IntArrayRC_H

#include "IntArray.h"

class IntArrayRC : public IntArray {
public:
IntArrayRC( int _size = DefaultArraySize );
IntArrayRC( int *array, int array_size );
IntArrayRC( const IntArrayRC&rhs );
/* virtual*/ int& operator[]( int );

private:
void check_range( int );
};

#endif
/*----------------------------*/
// IntArrayRC.cpp

#include "IntArrayRC.h"

IntArrayRC::IntArrayRC(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}
/*-------------------------------------------------------*/
// IntArray.cpp

#include "IntArray.h"

IntArray::IntArray(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}

/*-------------------------------------------------------*/
/* my pg49.cpp and IntArray.cpp didn't change */
/*--------- ----------*/
/* I tried to make everything simple, just hope to make it run, but
it still not work, and I don't see my IntArrayRC.cpp or pg49.cpp
reference
* IntArray::IntArray(int)' at all. how come compiler complain
that?
*/
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
/tmp/ccFlMagZ.o: In function `IntArrayRC::IntArrayRC(int*, int)':
IntArrayRC.cpp.text+0x15): undefined reference to
`IntArray::IntArray(int)'
collect2: ld returned 1 exit status
eric@eric-laptop:~/CppPrimer3$


looking to see any advancer's help again, and
Thanks a lot in advance,

You declared the constructor in 'IntArray' that takes a single 'int'
argument, but the argument has a default value, right? So, that makes
it the default constructor. Since 'IntArrayRC' does not initialize its
base class in any way, the compiler must use the default constructor.
And you didn't define it anywhere. Define it, and make sure your
compiler knows where it is.

V

 

[eric]

(e-mail address removed):
class IntArray {
public:
    // equality and inequality operations:  #2b
    explicit IntArray( int size = DefaultArraySize );
    IntArray( int *array, int array_size );
    IntArray( const IntArray&rhs );
    // virtual destructor!
    virtual ~IntArray() { delete [] ia; }
    // equality and inequality operations:
    bool operator==( const IntArray&  ) const;
    bool operator!=( const IntArray&  ) const;
    // assignment operator: #2a
    IntArray&  operator=( const IntArray&  );
    int size() const { return _size; }
// we've removed the check on the index...
    virtual int&  operator[](int index) { return ia[index]; }
    // int size() const;  // #1
    virtual void sort();       // #4
[...]
but my compile result( errors) is
--
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp pg49.cpp
/tmp/ccOnEojJ.o: In function `IntArray::IntArray(int*, int)':
IntArray.cpp.text+0x8): undefined reference to `vtable for IntArray'
With g++ this typically means you have not provided definition of the
first non-inline virtual function in this class. As far as I can see,
this would be IntArray::Sort(). Provide a definition of this function
(and all other non-defined virtual functions) in the relevant .cpp file.
In C++ one can in principle leave out definitions for functions which are
not used, but all virtual functions are effectively "used" for populating
the vtable entries, so they must be all present in the program.
hth
Paavo

/
***********************************************************************************************/

Thanks Paavo and Brian your reply on this undefined reference

now I delete more variables, functions in my IntArray.h and add
IntArrayRC.cpp(and IntArray.cpp)
/
***********************************************************************************************/
#ifndef IntArray_H
#define IntArray_H

class IntArray {
public:
    // equality and inequality operations:  #2b
    explicit IntArray( int size = DefaultArraySize );
    IntArray( int *array, int array_size );
    IntArray( const IntArray&rhs );

    // virtual destructor!
    // virtual ~IntArray() { delete [] ia; }

    // equality and inequality operations:
    bool operator==( const IntArray&  ) const;
    bool operator!=( const IntArray&  ) const;

    // assignment operator: #2a
    IntArray&  operator=( const IntArray&  );
    int size() const { return _size; }

// we've removed the check on the index...
    /* virtual */ int&  operator[](int index) { return ia[index];}
    // int size() const;  // #1
  //  virtual void sort();       // #4

    //virtual int min() const;  // #3a
    //virtual int max() const;    // #3b

    // if the value is found within the aray,
    // return the index of its first occurrence
    // otherwise, return -1

    /*virtual*/ int find ( int value ) const;    // #3c

   protected:
     // the private implementation
     static const int DefaultArraySize = 12;
     void init( int sz, int *array );

     int _size;
     int *ia;
};

#endif
/*--------------------*/
#ifndef IntArrayRC_H
#define IntArrayRC_H

#include "IntArray.h"

class IntArrayRC : public IntArray {
public:
   IntArrayRC( int _size = DefaultArraySize );
   IntArrayRC( int *array, int array_size );
   IntArrayRC( const IntArrayRC&rhs );
  /* virtual*/ int&  operator[]( int );

private:
   void check_range( int );
};

#endif
/*----------------------------*/
// IntArrayRC.cpp

#include "IntArrayRC.h"

IntArrayRC::IntArrayRC(int *iarray, int iarray_size)
{
   ia = iarray;
   _size = iarray_size;
}
/*-------------------------------------------------------*/
// IntArray.cpp

#include "IntArray.h"

IntArray::IntArray(int *iarray, int iarray_size)
{
   ia = iarray;
   _size = iarray_size;
}

/*-------------------------------------------------------*/
/* my pg49.cpp and IntArray.cpp didn't change            */
/*---------                                   ----------*/
/*  I tried to make everything simple, just hope to make it run, but
it still not work, and I don't see my IntArrayRC.cpp or pg49.cpp
reference
  *   IntArray::IntArray(int)' at all.  how come compiler complain
that?
  */
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
/tmp/ccFlMagZ.o: In function `IntArrayRC::IntArrayRC(int*, int)':
IntArrayRC.cpp.text+0x15): undefined reference to
`IntArray::IntArray(int)'
collect2: ld returned 1 exit status
eric@eric-laptop:~/CppPrimer3$

looking to see any advancer's help again, and
Thanks a lot in advance,

You declared the constructor in 'IntArray' that takes a single 'int'
argument, but the argument has a default value, right?  So, that makes
it the default constructor.  Since 'IntArrayRC' does not initialize its
base class in any way, the compiler must use the default constructor.
And you didn't define it anywhere.  Define it, and make sure your
compiler knows where it is.

V

Dear Victor Bazarov or any advanced c++ programer:

then I add
-------
IntArray::IntArray(int size = DefaultArraySize)
{
_size = size;
}
-----
to the end of my IntArray.cpp
then still not work
--------
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
IntArray.cpp:11:47: error: default argument given for parameter 1 of
‘IntArray::IntArray(int)’
IntArray.h:7:13: error: after previous specification in
‘IntArray::IntArray(int)’
---------
the only place I put (declare) IntArray(int) is in IntArray.h and in
the sentence
---------
explicit IntArray( int size =
DefaultArraySize);
in

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray &rhs );

 

[Victor Bazarov]

(e-mail address removed):

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray&rhs );

// virtual destructor!
virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
virtual int& operator[](int index) { return ia[index]; }
// int size() const; // #1
virtual void sort(); // #4

[...]

but my compile result( errors) is

With g++ this typically means you have not provided definition of the
first non-inline virtual function in this class. As far as I can see,
this would be IntArray::Sort(). Provide a definition of this function
(and all other non-defined virtual functions) in the relevant .cpp file.

In C++ one can in principle leave out definitions for functions which are
not used, but all virtual functions are effectively "used" for populating
the vtable entries, so they must be all present in the program.


Thanks Paavo and Brian your reply on this undefined reference

now I delete more variables, functions in my IntArray.h and add
IntArrayRC.cpp(and IntArray.cpp)
/
***********************************************************************************************/
#ifndef IntArray_H
#define IntArray_H

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray&rhs );

// virtual destructor!
// virtual ~IntArray() { delete [] ia; }

// equality and inequality operations:
bool operator==( const IntArray& ) const;
bool operator!=( const IntArray& ) const;

// assignment operator: #2a
IntArray& operator=( const IntArray& );
int size() const { return _size; }

// we've removed the check on the index...
/* virtual */ int& operator[](int index) { return ia[index]; }
// int size() const; // #1
// virtual void sort(); // #4

//virtual int min() const; // #3a
//virtual int max() const; // #3b

// if the value is found within the aray,
// return the index of its first occurrence
// otherwise, return -1

/*virtual*/ int find ( int value ) const; // #3c

protected:
// the private implementation
static const int DefaultArraySize = 12;
void init( int sz, int *array );

int _size;
int *ia;
};

#endif
/*--------------------*/
#ifndef IntArrayRC_H
#define IntArrayRC_H

#include "IntArray.h"

class IntArrayRC : public IntArray {
public:
IntArrayRC( int _size = DefaultArraySize );
IntArrayRC( int *array, int array_size );
IntArrayRC( const IntArrayRC&rhs );
/* virtual*/ int& operator[]( int );

private:
void check_range( int );
};

#endif
/*----------------------------*/
// IntArrayRC.cpp

#include "IntArrayRC.h"

IntArrayRC::IntArrayRC(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}
/*-------------------------------------------------------*/
// IntArray.cpp

#include "IntArray.h"

IntArray::IntArray(int *iarray, int iarray_size)
{
ia = iarray;
_size = iarray_size;
}

/*-------------------------------------------------------*/
/* my pg49.cpp and IntArray.cpp didn't change */
/*--------- ----------*/
/* I tried to make everything simple, just hope to make it run, but
it still not work, and I don't see my IntArrayRC.cpp or pg49.cpp
reference
* IntArray::IntArray(int)' at all. how come compiler complain
that?
*/
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
/tmp/ccFlMagZ.o: In function `IntArrayRC::IntArrayRC(int*, int)':
IntArrayRC.cpp.text+0x15): undefined reference to
`IntArray::IntArray(int)'
collect2: ld returned 1 exit status
eric@eric-laptop:~/CppPrimer3$

looking to see any advancer's help again, and
Thanks a lot in advance,

You declared the constructor in 'IntArray' that takes a single 'int'
argument, but the argument has a default value, right? So, that makes
it the default constructor. Since 'IntArrayRC' does not initialize its
base class in any way, the compiler must use the default constructor.
And you didn't define it anywhere. Define it, and make sure your
compiler knows where it is.

V

Dear Victor Bazarov or any advanced c++ programer:

then I add

Say, do you *read* the error messages? Do you try to comprehend them?
Or do you just copy-paste and post them here? Do you have a book that
explains default arguments at all?...

Drop the default value declaration from the function definition. Make
it look like this:

IntArray::IntArray(int size)

{
_size = size;

Read the FAQ, section 10.

}
-----
to the end of my IntArray.cpp
then still not work
--------
eric@eric-laptop:~/CppPrimer3$ g++ IntArray.cpp IntArrayRC.cpp
pg49.cpp
IntArray.cpp:11:47: error: default argument given for parameter 1 of
‘IntArray::IntArray(int)’
IntArray.h:7:13: error: after previous specification in
‘IntArray::IntArray(int)’
---------
the only place I put (declare) IntArray(int) is in IntArray.h and in
the sentence
---------
explicit IntArray( int size =
DefaultArraySize);
in

class IntArray {
public:
// equality and inequality operations: #2b
explicit IntArray( int size = DefaultArraySize );
IntArray( int *array, int array_size );
IntArray( const IntArray&rhs );

Let's make it your last before you try thinking...

V