[gdal-dev] Add capability to safely link against an external libtiff (3.X) and a GDAL build with internal libtiff (4.0) support

[Antonio Valentino]

Hi Even,

Il 04/07/2011 19:52, Even Rouault ha scritto:
>> Even, all tests i performed (ubuntu 11.04 only) passed successfully so I
>> can confirm that the patch works.
> 
> Great
> 
>>
>> My only concern is that I'm not able to reproduce the crash in cases in
>> which GDAL is built without symbol renaming.
> 
> Hum, did you activate --with-hide-internal-symbols ? I somehow remember that 
> it paradoxically helped revealing the duplicate symbol issues.

Yes, I tested the both "hide internal symbols" and no symbol hiding with:

* gdalinfo linked against gdal libtiff libgeotiff
* gdalinfo linked against libtiff libgeotiff gdal
* a simple test program that just open a tif file with GDAL and TIFF API
* gdal_translate linked against libtiff libgeotiff gdal

The last test (the one with gdal_translate) also implies writing a TIFF
file.

None of this tests produced a segfault even if in some cases I get
warnings about linking against the wrong libtiff version (one of the
changes you applied recently if I remember well).

I clearly remember I was on debian when a experimented the problem some
time ago even if I don't understand why this should make any difference
if I build GDAL with the same compilation flags.

I'm going to do some test with Julien's programs tonight.

regards

-- 
Antonio Valentino