Re: Thoughts on llvm/clang in base

[John Marino <dragonflybsd@xxxxxxxxx>]

On 10/15/2012 16:33, B. Estrade wrote:
> On Mon, Oct 15, 2012 at 03:17:08PM +0100, peeter (must) wrote:
>> On Mon, Oct 15, 2012 at 2:39 PM, B. Estrade<estrabd@gmail.com>  wrote:
>>> Just throwing this out there, but one thing that made me sad about
>>> FreeBSD's dumping GCC as base was that it was also dumping OpenMP
>>> support. Given that SMP is the goal, it was a pretty hefty technical
>>> benefit that was thrown away for mostly political reasons. I hope
>>> OpenMP support in clang/LLVM is bolstered in practice, there are certainly
>>> a number of academic efforts using it for OpenMP research. I am not
>>> aware of a strong clang/LLVM effort to support it outside of that arena,
>>> though. That DF has GCC with faily current OpenMP support in base is a
>>> strong reason for me to consider using it primarily over FreeBSD,
>>> which is my traditional go-to BSD.
>>>
>>> Thank you,
>>> Brett
>>
>>
>> Just to chime in with this, we're using OpenMPI on DF and it'd be
>> very, very bad news for us if support for OpenMPI would be
>> discontinued for the mentioned reason. We'd need to change the
>> platform then. . .
>>
>> Cheers, Peeter
>
> Do you mean OpenMP (shared memory) or OpenMPI (message passing?).
>
> OpenMPI is a separate library and not tied into a compiler or its
> runtime like OpenMP is (e.g., "GOMP" is the GCC project to handle the
> frontend/transformations/runtime).
>

DragonFly will probably continue with its unique 2-compiler 
configuration for the long term.  If clang is brought into base, it 
would be at the expense of GCC 4.4.  GCC 4.7 will probably have 
longevity because it doesn't need C++ to build while GCC4.8 and 
clang/llvm do.  So I think nobody will have to make a choice -- even if 
DF in time switches to clang as the default compiler, nothing stops 
users from setting the "backup" gcc47 as the default.

Now, does OpenMP support require libGOMP?  Becaues that's not been built 
right now.  Neither is libssp, which is the cause of a couple of package 
failures so I am thinking about having libssp in base.

John