One of the LLD developers, Rui Ueyama, looks back at the progress LLD did in 2016, see http://lists.llvm.org/pipermail/llvm-dev/2016-December/107981.html.
- "Now I'm pretty sure that that [LLD] is going to be a serious (and better, in my opinion) alternative to the existing GNU linkers [..]."
- "LLD is now able to link most x86-64 userland programs."
- "The FreeBSD project and we are trying to make LLD the system default linker of the operating system, and except a few tricky programs such as the kernel or a bootloader, the linker works mostly fine." Already achieved!
- "LLD supports x86, x86-64, x32, AArch64, AMDGPU, ARM, PPC64 and MIPS32/64,
though completeness varies."
- "[T]here are already a few systems that are using LLD as system
linkers, such as CloudABI or Fuchsia. Chromium and Clang/LLVM itself has
build options to use LLD to build them."
And, as a bonus:
- "LLD got faster [..] At the beginning of this year,
LLD took about 16 seconds to produce a 1.5 GB clang (debug build)
executable. Now, it takes about 14.5 seconds on single core and 8.5 seconds
on 20 cores. ld.gold takes about 25 seconds and 20 seconds,
respectively. [..] If you have a problem of too long link time, I'd recommend to try LLD."
Update spring 2017 According to one of the developers "LLD/ELF is now ready for production use at least for x86-64 (and probably for AArch64 and MIPS).", see http://lists.llvm.org/pipermail/llvm-dev/2017-March/111083.html
It also contains a brief description on how to make use of LLD.