It indeed is a journey for the most patient of us. Or, at least, was about 8 years ago, when I needed to build gcc for the Cortex M3 target. I guess not much has changed since then, and one still has a great opportunity to learn what mpfr, gmp and the rest of scary words mean, before either giving up or pushing through that crap. It's like eating super hot peppers: first one suffers, then enjoys the knowledge that they are a tough one. And maybe an endorphin rush, if they have suffered intensely enough.