ptrdiff_t misuse [was :Re: (empty)]

[Dmitry Antipov]

On 06/29/2012 05:20 PM, Eli Zaretskii wrote:

> Dmitry, could you please explain the reason(s) for the change below?
>
> Vertical positions in a window can never be large enough to justify
> using ptrdiff_t (on platforms where that is wider than a 32-bit
> 'int').  These are pixel positions on the Emacs display, so they
> cannot be too large.  The type of 'first_vpos' looks especially
> strange, since it is explicitly set to 1 at most.  I'm not aware of a
> platform where an 'int' is not wide enough for a value 1 ;-)

Argh, I misuse them against window_end_pos and window_end_bytepos,
which are positions in a buffer and so ptrdiff_t :-(.  This should
be reverted.

Dmitry