So I added +libpng12 to feeds/xorg/lib/imlib2/Makefile, what do I need to do to get the build system recognize that I've specified the dependency?  Even after this update it still complains that imglib2
"is missing dependencies for:" libpng12.  I have a total rebuild after "make clean" running, but I'm
hoping that (1) that works, and (2) that there's an easier way?

More generally, is the trunk expected to be often broken?  Is there some branch a humble
developer should be working from instead?

Thanks,
Andy