[Qgis-developer] QGIS setup with Qt 5 on mac

[Diane Perez]

Dear QGIS developers,

First of all, thank you very much for the great job, I have been a very happy user for years !

I would like to contribute now to the development, but I found myself stuck at the installation of dependencies.

According to the instructions of the INSTALL file provided with the source code, mac users should use Qt 4 and compile and install a bunch of dependencies for which binaries are not available (mainly Spatialindex, SIP, QScintilla2, PyQt, Qwt and bison) before being able to compile QGIS. I followed the instructions and got stuck at compiling QGIS as the master now requires Qt 5.

Now as I actually started by installing Qt 5 by mistake, I had the opportunity to see that it leads to a lot of problems to compile the dependencies. As far as I understand, Qt 5 requires C++11, which means one must use the new libc++ library instead of the old libstdc++ (at least on my configuration, with El Capitan and clang/llvm). Some modifications are such that mixing both is not possible, so everything must be compiled from start with C++11 and libc++. Unfortunately most of the dependencies I mention above do not compile without tweaking, and I stopped doing it when it started meaning not only modifying the Makefiles but the code itself...

I guess some of you work on mac, and have a far better understanding of all this than me. So my question is : how did you install those dependencies to compile the last version of QGIS with Qt 5 ? 

Did you have to compile again all of them or only a subset using Qt 5 and C++11 ? If so, how did you do it ? I got stuck at Qwt (6.1.3) which uses lots of functions deprecated in Qt 5.

I hope someone can give me pointers, as I would really like to contribute to QGIS (and hopefully fix a few bugs bugging me) !

Best regards,
Diane