sys-devel/llvm-3.3-r1 depends on app-admin/chrpath which is keyworded at least on OSX From the description of package app-admin/chrpath, this package doesn't work on Mach-O executable too.
Definitely doesn't. It will first fail because LDR (the variable holding what to pass to the compiler to set a rpath) is not defined on darwin. Once you correct that you hit a brick wall because it relies on elf.h which is given by glibc on linux. I am trying to emerge clang-3.3-r1 on x86-macos with the dep to chrpath removed.
chrpath should indeed not be in the deps on non-ELF systems (such as Darwin/OSX)
fixed, thanks