Abstract constructor initialisers

[major_tom3]

I have a class derived from an abstract base class, which is in turn
derived from a further ABC:

template< typename T > class CAbstractMatrix{...};

template< typename T > class CAbstractSquareMatrix: public
CAbstractMatrix< T >{...};

template< typename T > class CDiagonalMatrix : public
CAbstractSquareMatrix< T >{...};

Can anyone tell me why this constructor initialiser:

template< typename T > CDiagonalMatrix< T >::CDiagonalMatrix( unsigned
long nRows, T* pData, bool bAdopt = false )

: CAbstractSquareMatrix< T >( pData, nRows, bAdopt ) // works

{

...

}

calls CAbstractSquareMatrix< T >::CAbstractSquareMatrix( unsigned long,
T*, bool) as intended, but the latter:

template< typename T > CAbstractSquareMatrix< T

::CAbstractSquareMatrix( T* pData, unsigned long nSize, bool

bAdopt = false )

: CAbstractMatrix< T >( pData, nSize, bAdopt ) // doesn't work!

{

...

}

fails to call CAbstractMatrix< T >::CAbstractMatrix( T*, unsigned long,
bool) in its turn? Everything compiles fine; don't be put off by my
changing the order of the parameters between classes. The code fails at
run-time because the base-base-class's constructor is not called.

Thanks,

tom
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[Ryan Winter]

major_tom3 wrote:

I have a class derived from an abstract base class, which is in turn
derived from a further ABC:

template< typename T > class CAbstractMatrix{...};

template< typename T > class CAbstractSquareMatrix: public
CAbstractMatrix< T >{...};

template< typename T > class CDiagonalMatrix : public
CAbstractSquareMatrix< T >{...};

Can anyone tell me why this constructor initialiser:

template< typename T > CDiagonalMatrix< T >::CDiagonalMatrix( unsigned
long nRows, T* pData, bool bAdopt = false )
: CAbstractSquareMatrix< T >( pData, nRows, bAdopt ) // works
{
...
}

calls CAbstractSquareMatrix< T >::CAbstractSquareMatrix( unsigned long,
T*, bool) as intended, but the latter:

template< typename T > CAbstractSquareMatrix< T >::CAbstractSquareMatrix(
T* pData, unsigned long nSize, bool bAdopt = false )
: CAbstractMatrix< T >( pData, nSize, bAdopt ) // doesn't work!
{
...
}

fails to call CAbstractMatrix< T >::CAbstractMatrix( T*, unsigned long,
bool) in its turn? Everything compiles fine; don't be put off by my
changing the order of the parameters between classes. The code fails at
run-time because the base-base-class's constructor is not called.

I have no problems with this implementation.

Can you specify the compiler and platform you are using, and also post
working code.

Ryan