Re: [boost] Re: Request: BOOST_ENABLE_LONG_LONG

From: David Abrahams (dave_at_[hidden])
Date: 2003-02-16 08:10:33

Gennaro Prota <gennaro_prota_at_[hidden]> writes:

> On Sat, 15 Feb 2003 12:00:36 -0000, "John Maddock"
> <jm_at_[hidden]> wrote:
>
>>> Can't we detect
>>> whether the compiler is supporting "long long" and only enable the
>>> long long code under those circumstances?  In fact, /don't/ we do
>>> that?
>>>
>>> If this is just about inconvenient warnings, it seems to me that
>>> telling people "disable long long support or disable the warning" is a
>>> perfectly sensible approach.
>>>
>>> What am I missing?
>>
>>I agree completely: the issue is that older EDG compilers (prior to 3.0.0)
>>don't signal whether they're in strict mode or not
>
> Well, it's unfair to offload it on the compilers though. They aren't
> certainly obliged to tell you that a non standard type is not
> available. 

No they are not, but IIUC we don't default to assuming that it is
available.  We only decide that it's available if the compiler
explicitly tells us so.

> But I'm getting tired of all this discussion, I'm just replying for
> the equity's sake. Just to set records straight: the problem was not
> compilers; it's just that one should IMHO be able to compile, let's
> say, boost::is_integral in strict mode, unless she does use
> is_integral<long long>. 

And you can't do that today?

> If I just use is_integral<int>, why should I get errors?

You should not.

> As you know (see
>
> http://lists.boost.org/MailArchives/boost/msg29582.php
>
> ) __NO_LONG_LONG is just a 3.0 addition. There's a whole world of EDG
> front ends that don't have it, and there's a whole world of EDG users
> who want to compile in strict mode. BTW, Dave asked "can't we detect
> whether the compiler is supporting long long?". Can we?

I'd still like to know.  In the cases where we can't detect that long
long is unavailable, I agree with Gennaro that we should not assume it
will be available.  People use EDG compilers especially to check
conformance, and so are especially likely to run in strict mode.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com