cannot resolve overload to target type

[Chris Dean]

The code below compiles when BREAK_ME isn't defined.  Otherwise it
gives:

  test-algo.cc: In function `void AlgoSort(class List<int> *, int = 0, int = (-1))':
  test-algo.cc:48: cannot resolve overload to target type `void ()(class List<int> *)'
  test-algo.cc:48:   because no suitable overload of function `AlgoFixupSort' exists
  test-algo.cc:50: no matching function for call to `AlgoSort (int (*&)(const int *, const int *), void (*&)(List<int> *), List<int> *&, int &, int &)'

Can anyone point me in the right direction in my code or in g++?

Regards.
Chris Dean


#include <stdlib.h>
#include <string.h>

template <class T>
class List {
public:
    int len;
    T *array;

    int length() const { return( len ); }

    List() : len( 0 ), array( 0 ) {}
};

template <class T>
int AlgoStdCompare(const T* a, const T* b) {
  if (*a < *b)
    return -1;
  else
    return (*a > *b);	// 0 if equal, 1 if greater
}

int AlgoStdCompare(const char* const* a, const char * const*b)
{
    return strcmp(*a,*b);
}
     
template <class T>
void AlgoFixupSort(List< T >* , int, int ) {
}

template <class T> 
void AlgoSort(int (*compare)(const T *, const T *),
	  void (*fixup)( List<T> *, int first, int last),
	  List< T >* theList, int first, int last) {
  if (last < 0)
    last = theList->length()-1;
  
  qsort(theList->array+first, last-first+1, sizeof(T),
	(int (*)(const void *, const void *))compare);
  if (fixup)
    fixup(theList, first, last);
}

template <class T> 
void AlgoSort(List< T >* theList, int first = 0, int last = -1) {
  int (*compare)(const T*, const T*) = AlgoStdCompare;
  void (*fixup)( List<T> *, int first, int last) = AlgoFixupSort;
  
  AlgoSort(compare, fixup, theList, first, last);
}

int
main()
{
#ifdef BREAK_ME
    List<const char *> slist;
    AlgoSort( &slist );
#endif

    List<int> ilist;
    AlgoSort( &ilist );
}