Re: [PanoTools-devel] libpano12-2.8.1 released

[douglas w. <dgs...@ya...>]

Hi there,


----- Original Message ----
[snip]> Thanks for the report, this seem to be the same bug encountered by=
=20
> Manfred Kr=F6ger (libpano12.def doesn't export the same symbols as=20
> pano12.def).

> Hmm, this file was created specifically _not_ to export the TIFFxxxx=20
> symbols.  It's confusing that this release fails when 2.8.0 which=20
> was built against the same library versions is apparently ok (unless=20
> nobody bothered to report that).

Just some insight into all of this, seeing as I created the additional .def=
 files originally :-)
The reason that libpano12.def was created was specifically to _not_ export =
the tiff definitions. This was because of a somewhat subtle bug that is int=
roduced on the windows platform when the tiff definitions are re-exported a=
nd the panotools lib is built statically.=20

The short explanation (longer one on request :-)) is that the tiff library =
exists in two places, statically linked into the panotools library and _als=
o_ statically linked into the application (in my case hugin). Not only that=
 but those tiff functions available are linked from the pano12 and the rest=
 from libtiff. What then happens is that portions of the application code i=
ntialise the tiff library, but only in _one_ of the linked versions, leadin=
g to some wierd and intermittent errors, depending on the link order. By re=
moving the tiff exports, the application will only link to the tiff library=
 for tiff functions and all is well. This does not of course happen on the =
linux platform as all libraries are dynamically linked to pano12.so :-)

Unfortunately I could not remove the tiff exports out of pano12.def as (poo=
rly behaved) PTStitcher relied on them! Now that PTMender is available, per=
haps it is time once and for all to remove pano12.def?

regards,
Doug