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Re: When is the complete type of an external definition known?

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On 2012-08-19, Vlad from Moscow <vlad.moscow@mail.ru> wrote:
>> Vlad from Moscow <vlad.moscow@mail.ru> writes:
>> 
>> > Let consider a sample code
>> >
>> >     #include <stdio.h>    
>> >     static int a[];
>> >     int main( void )
>> >     {
>> >        printf( "sizeof( a ) = %ul\n", sizeof( a ) );
>> >        return 0;
>> >     }
>> >     extern int a[10];
>> 
>> > Shall a compiler issue an error for this sample code? Or the composite
>> > type of the array 'a' shall be known already in the point where the
>> > printf is used?
>
> According to paragraph 2 of section 6.9.2 External object definitions
> "If a translation unit contains one or more tentative definitions
> for an identifier, and the translation unit contains no external
> definition for that identifier, then the behavior is exactly as if
> the translation unit contains a file scope declaration of that
> identifier, with the composite type as of the end of the translation
> unit, with an initializer > equal to 0."

  static int a[];

violates 6.9.2 p3:
"If the declaration of an identifier for an object is a tentative
definition and has internal linkage, the declared type shall not be
an incomplete type."

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When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-19 13:40 -0700
  Re: When is the complete type of an external definition known? Keith Thompson <kst-u@mib.org> - 2012-08-19 14:06 -0700
    Re: When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-19 14:30 -0700
      Re: When is the complete type of an external definition known? Ike Naar <ike@iceland.freeshell.org> - 2012-08-19 21:56 +0000
        Re: When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-19 16:42 -0700
          Re: When is the complete type of an external definition known? Keith Thompson <kst-u@mib.org> - 2012-08-19 19:22 -0700
            Re: When is the complete type of an external definition known? Wojtek Lerch <wojtek_l@yahoo.ca> - 2012-08-20 10:57 -0400
              Re: When is the complete type of an external definition known? Keith Thompson <kst-u@mib.org> - 2012-08-20 13:01 -0700
                Re: When is the complete type of an external definition known? Wojtek Lerch <wojtek_l@yahoo.ca> - 2012-08-20 16:58 -0400
              Re: When is the complete type of an external definition known? pacman@kosh.dhis.org (Alan Curry) - 2012-08-21 00:44 +0000
          Re: When is the complete type of an external definition known? Ike Naar <ike@sverige.freeshell.org> - 2012-08-20 05:57 +0000
            Re: When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-20 03:22 -0700
              Re: When is the complete type of an external definition known? Ike Naar <ike@sverige.freeshell.org> - 2012-08-20 12:27 +0000
                Re: When is the complete type of an external definition known? Jens Gustedt <jens.gustedt@loria.fr> - 2012-08-20 17:04 +0200
                Re: When is the complete type of an external definition known? Ike Naar <ike@iceland.freeshell.org> - 2012-08-20 16:35 +0000
                Re: When is the complete type of an external definition known? Jens Gustedt <jens.gustedt@loria.fr> - 2012-08-20 20:43 +0200
          Re: When is the complete type of an external definition known? James Kuyper <jameskuyper@verizon.net> - 2012-08-20 08:46 -0400
  Re: When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-19 14:24 -0700
  Re: When is the complete type of an external definition known? "Ersek, Laszlo" <lacos@caesar.elte.hu> - 2012-08-19 23:36 +0200
    Re: When is the complete type of an external definition known? Vlad from Moscow <vlad.moscow@mail.ru> - 2012-08-19 14:46 -0700

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