I tried some of the examples with g++/cc and with clang. Clang is a lot better but it still produces some pretty ridiculous output (but not gigs of ridiculous output fortunately).
Oh, I totally agree. That said, these examples are engineered to make your compiler shit a brick. Most of the time clang++ gives you much more readable output. g++, however, is a lot more careful about your digits. It'll take a little while before clang++ gains serious traction in the scientific community.