windowscodecs: Workaround libtiff bug when it defines toff_t as 32-bit for 32-bit builds. Take 2.

[Dmitry Timoshkov]

Dmitry Timoshkov <dmitry at baikal.ru> wrote:

> > There's a TIFF_VERSION define that seems to have been renamed to
> > TIFF_VERSION_CLASSIC in 4.0.
> > 
> > It doesn't make sense to do the check at runtime, given we're only
> > going to link to one of the versions.
> 
> TIFF_VERSION_CLASSIC reflects the TIFF format itself, it's defined
> to 42, TIFF_VERSION_BIG introduced in 4.x defined to 43.
> 
> Unfortunately TIFFLIB_VERSION define reflects the date, not the real
> version. So for instance libtiff 3.9.7 has it defined to 20120922,
> 4.0.0 - 20111221, 4.0.1 - 20120218. I don't see a way to differentiate
> between 3.x and 4.x at compile time.

I see that this patch is now marked as 'pending'. Are my arguments not
clear enough?

-- 
Dmitry.