Re : Work around for compiler error parsing 'aligned' attribute? (Bug 11071)?

Have you looked at http://llvm.linuxfoundation.org/index.php/Main_Page?
They claim to build linux kernel with clang/llvm, after patching the kernel of course. May be some of these patch set can help you in the road of building uClibc with clang (last time I tried IIRC it wasn’t so easy, but it is nice to see someone else interesting on doing that).

Cheers,