pread, pwrite linux implementation does not conform to Single Unix Specification

[Ulrich Drepper]

On Wed, 2002-07-17 at 11:52, Andreas Schwab wrote:

> -			   __LONG_LONG_PAIR (0, offset));
> +			   __LONG_LONG_PAIR (-(offset < 0), offset));

Why do you use

  -(offset < 0)

instead of

  offset >> (sizeof (offset) * 8 - 1)

gcc 3.2 (well 3.3) will optimize the former to produce exactly the code
the latter code suggests but earlier versions of the compiler cannot do
this.  They need three instruction.

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