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Re: [COMMITED][v2] manual: Remove incorrect claim that qsort() can be stabilized

On Thu, 11 Dec 2014, Andreas Schwab wrote:
> Paul Eggert <> writes:
> > The last clause is incorrect.  C11 and POSIX both require that the
> > addresses passed to the comparison function must point to elements of the
> > original array, and glibc qsort conforms to the standards here.
> That is only true for bsearch:
>     "The comparison function pointed to by compar is called with two
>     arguments that point to the key object and to an array element, in
>     that order."
> The description for qsort does not say that:
>     "The contents of the array are sorted into ascending order according
>     to a comparison function pointed to by compar, which is called with
>     two arguments that point to the objects being compared."

No, Paul is right, see C99 Â7.20.5/C11 Â7.22.5, outside of the main 
description for qsort:

âThe implementation shall ensure that the second argument of the 
comparison function (when called from bsearch), or both arguments (when 
called from qsort), are pointers to elements of the array.â


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