Comment 7 for bug 679164

> It seems to be a matter personal preference which of the (combination)
> of proposed fixes is the best one:
> * pass -j1

Commited in rev. 76f04d672b03

>* Don't run make in a -j2 incompatible way, use "make all && make
> clean" instead of "make all clean"
This would require some more changes to be compatible with the progress dialog. So I decided for the easier way ;-)