On 03/17/2017 05:58 PM, Mark Johnson wrote: >>> Can you clarify on which systems you are working and which dependencies > cause headaches? > In my case I am working on an old machine, where many things have been > installed in the past and cause conflicts. So until a new machine can be > bought I am attempting to get this done in a custom application > directory, where QGIS is then called from a script where the > needed environment vars are set so that everything needed is found first. > In my case it is since there are QT3, QT4 and older QT5 installed. > So a separate, clean, QT5 is needed.
What would be interesting for such situations would be something like AppImage. I tried that some time ago but stopped because I got sidetracked. It would still be very interesting for a wider purpose. Some discussion can be found here: https://github.com/qgis/QGIS/pull/3784 If you manage to get this running, we will be able to offer cross-distribution downloads. I'll buy you some coffees or beers for that. > > At present I have everything compiled, but QGIS3 fails due to something, > some complaining about different libpng's being found: > > # libpng warning: Application was compiled with png.h from libpng-1.6.10 > # libpng warning: Application is running with png.c from libpng-1.2.56 > # libpng error: Incompatible libpng version in application and library > > Here I assume the default libcairo loads libpng-1.2.56, which QT5 > used libpng-1.6.10, which is installed in /usr/local/lib for librasterlite2. > > So at the moment I have installed libcairo using libpng-1.6.10 in > /usr/local/lib, and recompiling QT5 using the internal PNG/JPEG libs. I suspect these kind of conflicts differ from system to system and documenting them on a page could end up in a collection of red herrings. (I might be wrong here). > >>>In many situations, a build of Qt is not required and doing this > requires deep understanding of all the involved libraries. > Yes and the idea a Wiki page/area for 'Building QGIS from scratch' could > assist in making that easier. Feel free to start working on this :-) Matthias _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer