Just for the record: aMule compiles with llvm-gcc(4.2), but it segfaults upon start on x86_64. I'm sure whether it ran successfully the last time I tried it on my i686 machine a couple of months ago, but the compilation was a lot slower than with gcc.
Edit: In general it compiled faster code than gcc in less time for the C-code I tested, that's why I gave it a try.