Illumos is a fork of Solaris, itself a UNIX System V derived OS, very much not a BSD, though taking some code from BSD. I'm not sure what license they make new additions under, but the core is CDDL licensed and not BSD licensed, anyway.
(side tangent FWIW, NetBSD has no qualms with using GPLv3 GCC, only Free/Open do)
(Edit for another historical tangent: Sun helped create System V release 4, which specifically combined element of older SysV with BSD. Additionally, Solaris/"SunOS 5"'s predecessor SunOS 4 was a straight-up BSD. So Solaris is a pretty BSD-y UNIX, in a way...)
Well, yes -- it's nice and portable like that. I think at some point they got it building with PCC and TCC too?
My point is unlike the other BSDs they haven't made a point of deprecating/removing GCC from the source tree, or even using LLVM by default where they can. For third parties worried about GPLv3, you can easily delete all GPLv3 code with a rm -rf src/external/gpl3 :)
LLVM recently got a m68k backend. It's still marked experimental, so distros likely aren't enabling it yet. But it's seeing active developments from hobbyists. Main author of the m68k just had a book on LLVM published.
(side tangent FWIW, NetBSD has no qualms with using GPLv3 GCC, only Free/Open do)
(Edit for another historical tangent: Sun helped create System V release 4, which specifically combined element of older SysV with BSD. Additionally, Solaris/"SunOS 5"'s predecessor SunOS 4 was a straight-up BSD. So Solaris is a pretty BSD-y UNIX, in a way...)