Re: undefined reference(compile error), plz help
On Jun 9, 10:44 am, Victor Bazarov <v.baza...@comcast.invalid> wrote:
On 6/9/2011 1:25 PM, eric wrote:
On Jun 9, 12:44 am, Paavo Helde<myfirstn...@osa.pri.ee> wrote:
eric<cneric12l...@gmail.com> wrote in news:33ca3f4e-bbef-4072-9fc6-
dec670fff...@x38g2000pri.googlegroups.com:
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 fil=
e.
In C++ one can in principle leave out definitions for functions which =
are
not used, but all virtual functions are effectively "used" for populat=
ing
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 complai=
n
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
--
I do not respond to top-posted replies, please don't ask
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
=91IntArray::IntArray(int)'
IntArray.h:7:13: error: after previous specification in
=91IntArray::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 );
------------
so need your help again, Eric