[PATCH] D62215: Fixes to distribution example for X86_64 Arch Linux

Wed May 22 16:09:13 PDT 2019

winksaville added a comment.

> I actually really appreciate you trying this out and reporting back with such detailed feedback on your experience. Thank you for your patience, and I'm sorry if I'm being a bit of a pain.

Been a good learning experince for me, both LLVM and cmake, I hope you don't think I'm being pedantic or odd,
but I'm just trying to verify how things should work. Additionally, I want to get Arch Linux to provide static and
dynamic libraries for clang.

> I think the correct fix for this is to use lld on non-Darwin platforms, and that can be done by adding the following code to DistributionExample.cmake:
> 
>   if (NOT APPLE)
>     set(BOOTSTRAP_LLVM_ENABLE_LLD On CACHE BOOL "")
>   endif()
> 
> 
> This will force using LLD on non-Darwin builds. This combined with adding "libcxxabi" to `LLVM_ENABLE_RUNTIMES` should actually get your build working without any further changes (none of the gold stuff should be needed).

This seems a reasonable solution,

> Additionally we should probably consider adding better error checking to the bootstrap configurations to error out during configuration on some of these problems. For example we should be able to verify that when `BOOTSTRAP_LLVM_ENABLE_LTO=On` the following things should be true.
> 
> - If your host is Windows, in stage 1 you must be building `lld`, and in stage 2 you must be linking with it
> - If your host is Linux, in stage 1 you must be building `lld`, and in stage 2 you must be linking with it -or- you must build the Gold plugin in stage1 and link with `ld.gold` in stage 2.
> - If your host is Darwin, you must not be using `lld`

IIRC, on linux if LTO is ON I had to use `ld.gold` for both stage 1 and 2, although that maybe
just the way it ended up and it wasn't necessary. But I'll test whatever you come up with.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62215/new/

https://reviews.llvm.org/D62215