I'm not knowledgeable enough about portability of LLVM, but if it's binary compatible with GCC-compiled stuff (or can be made such) on Windows, then, sure.
See, the problem here is that if you want interop, with, eg. Ruby, Erlang, R, Perl, Go and probably a bunch of others (the only other exception I know of is PHP (PECL) that uses MS toolchain), then you have to produce compatible binaries.
Ideally, it shouldn't be about the flavor of compiler, but be some kind of official documented format... that many compilers can easily implement. But, since de facto this format is "just use GCC", then, in practical terms, either use GCC, or pretend you use GCC.
See, the problem here is that if you want interop, with, eg. Ruby, Erlang, R, Perl, Go and probably a bunch of others (the only other exception I know of is PHP (PECL) that uses MS toolchain), then you have to produce compatible binaries.
Ideally, it shouldn't be about the flavor of compiler, but be some kind of official documented format... that many compilers can easily implement. But, since de facto this format is "just use GCC", then, in practical terms, either use GCC, or pretend you use GCC.