Remove algo logic duplication Round 3

[Paolo Carlini]

Hi,

FYI...

On 09/23/2013 10:07 PM, François Dumont wrote:
>     /// Swaps the median value of *__a, *__b and *__c under __comp to *__a
>     template<typename _Iterator, typename _Compare>
>       void
>       __move_median_first(_Iterator __a, _Iterator __b, _Iterator __c,
>   			_Compare __comp)
>       {
> -      // concept requirements
> -      __glibcxx_function_requires(_BinaryFunctionConcept<_Compare, bool,
> -	    typename iterator_traits<_Iterator>::value_type,
> -	    typename iterator_traits<_Iterator>::value_type>)
> -
> -      if (__comp(*__a, *__b))
> +      if (__comp(__a, __b))
>   	{
> -	  if (__comp(*__b, *__c))
> +	  if (__comp(__b, __c))
>   	    std::iter_swap(__a, __b);
> -	  else if (__comp(*__a, *__c))
> +	  else if (__comp(__a, __c))
>   	    std::iter_swap(__a, __c);
>   	}
> -      else if (__comp(*__a, *__c))
> +      else if (__comp(__a, __c))
>   	return;
> -      else if (__comp(*__b, *__c))
> +      else if (__comp(__b, __c))
>   	std::iter_swap(__a, __c);
>         else
>   	std::iter_swap(__a, __b);
>       }
Looks like something bad happened to this function: the changes to the 
__comp arguments can't be right. I'm going to fix it as part of applying 
Chris' patch. Please audit the rest of the patch for this kind of typo.

Paolo.