[LLVMdev] LLD Standalone CMake build

[Greg Fitzgerald]

I'm hoping to revive the LLD standalone CMake build.  I'm new to this
build but it looks like it borrowed code from an old version of
compiler-rt, which I did some work on last year.  Like compiler-rt,
I'd like to get the LLD build up running with only CMAKE_PREFIX_PATH
instead of defining custom variables like LLD_PATH_TO_LLVM_BUILD and
LLD_PATH_TO_LLVM_SOURCE.  Any objection to that?

Also, two files ELFLinkingContext.cpp and MachOLinkingContext.cpp
include a private header from the LLVM source tree,
"llvm/Config/config.h" to get access to HAVE_CXXABI_H.  Can the
dependency on HAVE_CXXABI_H be removed?  If no, mind if I add a
config.h.cmake to LLD's "include/lld/Config"?

Thanks,
Greg