WITH_LLD_IS_LD vs default WITHOUT_SYSTEM_COMPILER: What are the reasons?

[Ed Maste]

On 14 April 2017 at 20:16, Mark Millard <markmi at dsl-only.net> wrote:
> So it sounds like I can freely mix WITH_LLD_IS_LD and WITH_SYSTEM_COMPILER
> in any system-clang 4.0 based system build context, no actual problem
> cases, even if the existing system build used a binutils ld (for example).

Yes. WITH_LLD_IS_LD implying WITHOUT_SYSTEM_COMPILER was added because
LLD requires tblgen and libllvm, but they were originally built only
when needed for Clang. In cases where the SYSTEM_COMPILER default
logic determined that the host compiler was identical to the
to-be-built bootstrap compiler the build would skip building Clang,
tblgen, and libllvm. This was fixed by r316647 and the connection
between LLD_IS_LD and SYSTEM_COMPILER can be removed in due course.