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Re: va_args Conformance

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On 01/31/2012 11:53 AM, Ben Bacarisse wrote:
> James Kuyper <jameskuyper@verizon.net> writes:
> 
>> On 01/31/2012 09:50 AM, Ben Bacarisse wrote:
>>> Shao Miller <sha0.miller@gmail.com> writes:
>>>
>>>> If the following program strictly conforming?
>>>>
>>>>   #include <stddef.h>
>>>>   #include <stdarg.h>
>>>>
>>>>   static void test(int, ...);
>>>>
>>>>   int main(void) {
>>>>       test(0, 42);
>>>>
>>>>       return 0;
>>>>     }
>>>>
>>>>   static void test(int x, ...) {
>>>>       typedef unsigned char one_char[1];
>>>>       /* Valid declaration on the next line */
>>>>       one_char * unused;
>>>>       va_list varargs;
>>>>       unsigned char * byte;
>>>>
>>>>       va_start(varargs, x);
>>>>       if (x)
>>>>           byte = va_arg(varargs, one_char);
>>>>       va_end(varargs);
>>>>
>>>>       return;
>>>>     }
>>>
>>> It looks fine to me.  Does some implementation reject it?
>>
>> The second argument of his call to test() has a type of int. He calls
>> va_arg() with a type of one_char, which is a typedef for unsigned
>> char.
> 
> I though his code did not do this.  Was that not the point of the
> if (x) with x == 0?

You're right - I didn't pay attention to that. Sorry!

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Thread

va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 09:12 -0500
  Re: va_args Conformance Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-31 14:50 +0000
    Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 10:11 -0500
      Re: va_args Conformance Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-31 17:19 +0000
        Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 12:31 -0500
          Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 12:34 -0500
            Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 12:40 -0500
          Re: va_args Conformance Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-31 17:52 +0000
    Re: va_args Conformance James Kuyper <jameskuyper@verizon.net> - 2012-01-31 11:27 -0500
      Re: va_args Conformance Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-01-31 16:53 +0000
        Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 12:09 -0500
        Re: va_args Conformance James Kuyper <jameskuyper@verizon.net> - 2012-01-31 12:15 -0500
  Re: va_args Conformance Harald van Dijk <haraldvdijk@gmail.com> - 2012-01-31 09:46 -0800
    Re: va_args Conformance Shao Miller <sha0.miller@gmail.com> - 2012-01-31 13:45 -0500
      Re: va_args Conformance Harald van Dijk <haraldvdijk@gmail.com> - 2012-01-31 11:28 -0800
      Re: va_args Conformance Harald van Dijk <haraldvdijk@gmail.com> - 2012-01-31 11:33 -0800

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