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Re: [Patch] Support DEC-C extensions
On Fri, 30 Sep 2011 09:24:03 +0200
Tristan Gingold <gingold@adacore.com> wrote:
>
> On Sep 29, 2011, at 5:54 PM, Basile Starynkevitch wrote:
> > I believe that such an extension is useful on other systems, even when their ABI don't
> > pass the number of arguments.
> >
> > The use case I would have in mind is when the signature of the called function (that is
> > the number & types of arguments) is determined by something else, perhaps a global
> > variable or data. Think e.g. of a printf-like function, except that the format string is
> > conventionally assigned to some fixed global before calling it.
>
> In fact you can't access to the arguments with ANSI-C as va_start needs a named argument. So you can't write such code.
I agree with that point, but that suggests that such a function is not DEC like. (and
IIRC, in the good days of <vaargs.h> ten years ago, not today's <stdarg.h>, such a
function was possible).
I was only saying that there is no reason to call such an extension DEC-like. And
apparently, you tested it on a x86/Linux which is not a DEC system :-)
And I do think that such an extension can be useful.
Cheers.
--
Basile STARYNKEVITCH http://starynkevitch.net/Basile/
email: basile<at>starynkevitch<dot>net mobile: +33 6 8501 2359
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