musl - Re: [C23 128 bit 4/4] C23: implement proper support for int128_t and uint128

Follow @Openwall on Twitter for new release announcements and other news

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Wed, 31 May 2023 18:58:15 +0200
From: Jens Gustedt <jens.gustedt@...ia.fr>
To: musl@...ts.openwall.com
Subject: Re: [C23 128 bit 4/4] C23: implement proper support for int128_t and uint128_t

Am 31. Mai 2023 18:30:16 MESZ schrieb Alexander Monakov <amonakov@...ras.ru>:
> 
> On Wed, 31 May 2023, Jₑₙₛ Gustedt wrote:
> 
> > Again, this is not an extension but an optional feature, and this has
> > nothing of bleeding edge. This is present in compilers since ages, and
> > everybody is using their specific ways to go around the restrictions
> > of previous C standards.
> 
> So, to make sure, by compiler support do you mean __int128 here?

yes

> It is
> not supported on 32-bit platforms neither by GCC nor by LLVM. On 64-bit
> platforms it is piggy-backing on double-word operations support required
> for implementing 64-bit 'long long' on 32-bit platforms.

So what? On the arch where it exist, it is used and useful. (And I also think that implementations improved over the state from 20 years ago that you describe.)

Nobody is talking about offering it on compilers where there is no support. With the proposed patches this becomes  an optional feature with feature tests. A real improvement for users, that up to now have to guess on their own.

Jens

-- 
Jens Gustedt - INRIA & ICube, Strasbourg, France

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.