[Openembedded-architecture] Bringing clang to OE-Core

[Denys Dmytriyenko]

On Thu, Apr 07, 2016 at 01:51:19PM -0700, Khem Raj wrote:
> 
> > On Apr 7, 2016, at 1:39 PM, Phil Blundell <pb at pbcl.net> wrote:
> > 
> > On Thu, 2016-04-07 at 10:25 -0700, Khem Raj wrote:
> >> There has been steady demand for clang infrastructure in OE from multiple users and developers. I have therefore opened a feature enhancement
> >> request, its being used primarily in SDKs by some users. Its in good shape for most of architectures which are supported in OE-Core.
> >> 
> >> https://bugzilla.yoctoproject.org/show_bug.cgi?id=9417
> >> 
> >> to bring meta-clang into OE-core as additional compiler option.
> > 
> > What is the advantage of merging it into oe-core rather than maintaining
> > it as a separate layer?  Are there other (existing/proposed) recipes in
> > oe-core that would benefit from it?
> 
> you can benefit from using compile you want.
> 
> > 
> > You mentioned that it's being used "primarily in SDKs".  How confident
> > are you that everything else in oe-core is indeed compilable with clang?
> 
> most ( barring 25 odd) recipes
> build fine with clang in OE-Core. I have large images with webkit and qt which
> are using clang as default compiler but there are certain packages which just
> don’t behave.
> 
> > 
> > To be honest, my personal reaction is that if we have two compilers in
> > oe-core then we're just going to have twice as many compiler bugs to
> > contend with, and unless there is some very compelling win from having
> > it merged I would leave it out.  But of course it's not me that makes
> > the decisions.
> 
> I am just fine to maintain it as external layer, I am looking for if there is
> enough interest that makes sense to move it to Core. This impacts
> core piece of infrastructure and it will benefit from being closer to
> that core. Not mentioning that OE-Core would become usable for clang interested
> users and distros.

I have discussed this with Khem during ELC this week. My specific usecase is 
not necessarily requiring clang, but rather LLVM. We have some DSP code 
generation tools based on LLVM that I would love to add to meta-ti BSP layer, 
but don't want an extra dependency on meta-openembedded or any other layer.

So, my specific request would be to bring LLVM recipes to oe-core. Currently 
those are duplicated in at least 4 layers and it seems the latest one is in 
meta-amd. Moving LLVM to OE-Core would benefit us all.

The reason I support Khem's proposal is because clang depends on LLVM and it 
would bring the pieces I require along with it to OE-COre. :)

-- 
Denys