ld.lld-12 segfault

Hello,

I've been trying the RCs for clang 12 and I've noticed that the linker
sometimes segfaults when using thin-lto.

I've tried the same build using clang 11 and it works, so it's clearly
a regression. I've installed the ubuntu packages from apt.llvm.org,
which don't seem to come with debug symbols.

Is there an easier way to debug this segfault besides compiling the
whole of LLVM from source? Can I find matching packages with debug
symbols somewhere?

With regards,
Martijn Otto