[llvm-dev] [cfe-dev] GN build roundtable summary; adding GN build files to the repo

[John Paul Adrian Glaubitz via llvm-dev]

Hi!

On 11/1/18 5:44 PM, Brian M. Rzycki via llvm-dev wrote:
> GN is the current build darling of Google. However, on my Red Hat and Ubuntu hosts there are no packages to install and others have pointed out certain architectures aren't supported with GN today. Until gn is a 'dnf install gn' or 'apt install gn' away this makes the build dependencies on LLVM more onerous.

Jepp, that's basically my main argument. Apparently, the current plan seems to be
"Let's integrate it first, then we'll resolve the issues that GN currently has
 some time later."

> I'm also a bit hesitant because the culture at Google seems to quickly deprecate services and tools for "the-next-new-shiny".  I remember when Chromium and the AOSP used makefiles and moved to GYP. And now GN is replacing GYP in several projects. That's two build system overhauls in the span of about 4 years.

That's really short. I would fear that Google drops GN only short time later and
then we are left with something in LLVM that is unmaintained and unsupported by
upstream.

> I would rather have the discussion of the pros/cons of fully replacing CMake and all that would entail for a complex project like LLVM.

And keeping in mind that LLVM is an extremely important project that a lot of downstream
projects are building on because of the fact that a lot of languages like Rust and Julia
are relying on LLVM as their code-generating backend. So, if you break the build system,
you will get a lot of angry downstream users.

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz at debian.org
`. `'   Freie Universitaet Berlin - glaubitz at physik.fu-berlin.de
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