[flang-dev] [RFC] Refactor Clang: move frontend/driver/diagnostics code to LLVM

[Doerfert, Johannes via flang-dev]

On 6/9/20 10:12 AM, Andrzej Warzynski wrote:
> On 02/06/2020 18:04, Chris Tetreault wrote:
> > I wonder if, instead of just putting it in llvm, it makes sense to 
> have some sort of "llvm-frontend" subproject?
>
> There seems to be preference to move this common-code into a separate 
> project. Keep in mind that we already have llvm/lib/Frontend which was 
> created recently for this kind of functionality (see [1] & [2], also 
> CC'ed Johannes). The new library that we propose would be shared 
> between subprojects (initially just clang and flang) and it feels that 
> we tend to use LLVM for such things (e.g. FileCheck, LIT, bits of 
> TableGen). Do we really want a separate subproject for the common 
> Driver code?
>
> Out of the proposed names I feel that 'frontend-support' would be the 
> most accurate name (nothing clang, flang or llvm specific, just 
> language agnostic code to share between various frontends, including 
> some infra). That's the name I will be using below, though we still 
> need to decide whether it's going to be a subdirectory within LLVM or 
> a new subproject.

I'm not against a subproject *but* if we also move the existing 
llvm/lib/Frontend stuff, that would introduce a dependence from 
llvm-core to this project, which I think is uncommon. We could also have 
both. At the end of the day it depends on the benefit we would get from 
an independent subproject.