an oldie but a goodie .. ISO C90 does not support 'long long'

[raf]

On Sat, Nov 05, 2022 at 02:22:55PM +0000, Michael Wojcik <Michael.Wojcikatmicrofocus.com> wrote:

> > From: openssl-users <openssl-users-bounces at openssl.org> On Behalf Of raf via
> > openssl-users
> > Sent: Friday, 4 November, 2022 18:54
> > 
> > On Wed, Nov 02, 2022 at 06:29:45PM +0000, Michael Wojcik via openssl-users
> > <openssl-users at openssl.org> wrote:
> > 
> > >
> > > I'm inclined to agree. While there's an argument for backward compatibility,
> > > C99 was standardized nearly a quarter of a century ago. OpenSSL 1.x is
> > > younger than C99. It doesn't seem like an unreasonable requirement.
> > 
> > Would this be a choice between backwards-compatibility with C90
> > compilers and compatibility with 32-bit architectures?
> 
> I don't see how.
> 
> It's a question of the C implementation, not the underlying
> architecture. A C implementation for a 32-bit system can certainly
> provide a 64-bit integer type. If that C implementation conforms to
> C99 or later, it ought to do so using long long and unsigned long
> long. (I'm excluding C implementations for exotic systems where, for
> example, CHAR_BIT != 8, such as some DSPs; those aren't going to be
> viable targets for OpenSSL anyway.)
> 
> > Is there another way to get 64-bit integers on 32-bit systems?
> 
> Sure. There's a standard one, which is to include <stdint.h> and
> use int64_t and uint64_t. That also requires C99 or later and an
> implementation which provides those types; they're not required.

Sorry. I assumed that it was clear from context that I was only
thinking about C90-compliant 64-bit integers on 32-bit systems.

> And for some implementations there are implementation-specific
> extensions, which by definition are not standard.
> 
> And you can roll your own. In a non-OO language like C, this would
> be intrusive for the parts of the source base that rely on a 64-bit
> integer type.
> 
> > I suspect that that there are more 32-bit systems than there are
> > C90 compilers.
> 
> Perhaps, but I don't think it's relevant here. In any case, OpenSSL is
> not in the business of supporting every platform and C implementation
> in existence. There are the platforms supported by the project, and
> there are contributed platforms which are included in the code base
> and supported by the community (hopefully), and there are unsupported
> platforms.
> 
> If someone wants OpenSSL on an unsupported platform, then it's up to
> them to do the work.

So it sounds like C90 is now officially unsupported.
I got the impression that, before this thread, it was believed
that C90 was supported, and the suggestion of a pull request
indicated a willingness to retain/return support for C90.
Perhaps it just indicated a willingness to accept community
support for it.

I'd be amazed if anyone could actually still be using a
30 year old C90 compiler, rather than a compiler that
just gives warnings about C90. :-)

> -- 
> Michael Wojcik

cheers,
raf