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Re: pread, pwrite linux implementation does not conform to SingleUnix Specification
Ulrich Drepper <drepper@redhat.com> writes:
|> 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)
Because that is obvious.
|> instead of
|>
|> offset >> (sizeof (offset) * 8 - 1)
Because right shifting of negative numbers is implementation-defined, and
I didn't know that older gcc optimize it better.
Andreas.
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Andreas Schwab, SuSE Labs, schwab@suse.de
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