Почему valgrind показывает утечку?

template < size_t precision_T, size_t base_T >
class BigFloat {
  public:
    BigFloat(const char *source);
    ~BigFloat();
  private:
    int *buf_;
    int *exp_;
    int findNum(const char symbol);
};
 
template < size_t precision_T, size_t base_T >
int BigFloat< precision_T, base_T >::findNum(const char symbol) {
  char reg[] = {'0','1','2','3','4','5','6','7','8','9'};
  int j = 0;
  while (symbol != reg[j] && j < 10) {
    j++;
  }
  if (j == 10)
    assert(!"Unknown character!");
  return j;
}
 
template < size_t precision_T, size_t base_T >
BigFloat< precision_T, base_T >::BigFloat(const char *source) :
  end_of_number_(0),
  buf_(new int[precision_T]),
  exp_(new int[precision_T])
{
  int length = strlen(source);
  int k = 0;
  while (source[k] != '.' && k < length) {
    exp_[0] *= base_T;
    exp_[0] += findNum(source[k]);
    k++;
  }
  length--;
  for (int i = k; i < precision_T; i++) {
    exp_[i] = 0;
    buf_[i] = 0;
    if (i < length) {
      k++;
      if (i != 0)
        exp_[i] = findNum(source[k]);
      end_of_number_ = i;
    }
  }
}
 
template < size_t precision_T, size_t base_T >
BigFloat< precision_T ,base_T >::~BigFloat() {
  delete [] exp_;
  delete [] buf_;
  exp_ = NULL;
  buf_ = NULL;
  end_of_number_ = 0;
}
 
int main() {
  BigFloat<10,10> *sqrt2 = new BigFloat<10,10>("1.4142");
  sqrt2->~BigFloat();
}

  BigFloat<10,10> *sqrt2 = new BigFloat<10,10>("1.4142");
  delete sqrt2 ;