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From: Daryle Walker (dwalker07_at_[hidden])
Date: 2003-06-20 13:33:10


On Friday, June 20, 2003, at 12:38 AM, Gennaro Prota wrote:

> On Fri, 20 Jun 2003 00:49:42 -0400, Daryle Walker <dwalker07_at_[hidden]>
> wrote:
>
>> On Wednesday, June 18, 2003, at 9:59 PM, David Abrahams wrote:
>
>>> Slightly. They are still "non-portable constructions made up by
>>> compiler makers."
>>
>> As I understand it, the #include directive dumps the contents of a
>> file found from the standard (<>) and/or user ("") header space. The
>> only degrees of variance is how the mapping of header names to
>> files/sources occurs and how the standard headers are handled.
>
> Really?
>
> http://www.google.com/
> groups?threadm=plfbev89vgf08s0o3848bjssetqtqn0at9%404ax.com

There is nothing in that thread that affects what I said. That poster
is asking about the specifics of the implementation-defined mapping,
I'm just stating the existence of it.

> Also, I have resisted once but now you want to make me suffer :-)
>
>> From another post in this thread:
>
>> Warnings are completely non-portable, since:
>
>> 1. They have no official standing in the standard, just errors do
> ^^^^^^^^^^^^^^

[My mail client badly wrapped here. The "^" underlined the "errors do"]

> Really?

There're called "diagnostics" in the standard (besides the "#error"
directive).

>> [...]
>> 3. They are 100% legal code, the vendor just doesn't like it
>
> Really?

Yes. If they wasn't legal code, the compiler would have to flag it as
an error. Undefined behavior can exist (so change my 100% to 90+%),
but it's something the complier can't statically determine. The
warning mechanism can't find it either, since it's also limited to
static determination; it could flag code that has a high probability of
undefined behavior as a practical alternative.

>> Equating the implementation-defined parts of #include to the warning
>> concept, which has no official standing, is a gross >> misrepresentation.
>
> I don't think Dave was really equating. He was probably just saying
> that features not exactly specified, or not specified at all, by the
> standard can still be useful in practice.
>
> Not that I'm for BOOST_STATIC_WARNING, just to avoid such erroneous
> information about what is standard and what is not.

Daryle


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