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Re: Style question: Declaration of globals in header file

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"James R. Kuyper" <jameskuyper@verizon.net> writes:

> On 06/12/2017 12:00 PM, Steve Keller wrote:
> ...
>> Until now I thought tentative definition are there to allow easier
>> definition of objects with external linkage (i.e. only one definition
>> in a header file to be included several times).  Since that is not
>> allowed, I now wonder what the purpose of tentative definitions is.
>> I don't see much use of having them in *one* translation unit.
>
> I gather that at least one of the purposes it's intended to serve is
> to allow mutually recursive external definitions:
>
>
>     const void *first;
>     const void *second = &first;
>     const void *first = &second;

But that can be done without a tentative definition using extern on the
first declaration.  You could have given an example with all static
objects, but then that leaves the question of the purpose of tentative
definitions of names with external linkage open which is the main thrust
of the thread.

<snip>
-- 
Ben.

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Style question: Declaration of globals in header file Steve Keller <keller@no.invalid> - 2017-06-06 19:33 +0200
  Re: Style question: Declaration of globals in header file "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-06 14:21 -0400
    Re: Style question: Declaration of globals in header file Steve Keller <keller@no.invalid> - 2017-06-12 11:07 +0200
      Re: Style question: Declaration of globals in header file bartc <bc@freeuk.com> - 2017-06-12 11:03 +0100
      Re: Style question: Declaration of globals in header file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-12 11:40 +0100
      Re: Style question: Declaration of globals in header file James Kuyper <jameskuyper@verizon.net> - 2017-06-12 07:33 -0400
        Re: Style question: Declaration of globals in header file Steve Keller <keller@no.invalid> - 2017-06-12 18:00 +0200
          Re: Style question: Declaration of globals in header file "James R. Kuyper" <jameskuyper@verizon.net> - 2017-06-12 12:11 -0400
            Re: Style question: Declaration of globals in header file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-12 17:27 +0100
          Re: Style question: Declaration of globals in header file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-12 17:18 +0100
          Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-12 09:44 -0700
      Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-12 07:55 -0700
        Re: Style question: Declaration of globals in header file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-12 16:51 +0100
  Re: Style question: Declaration of globals in header file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-06-06 19:21 +0100
  Re: Style question: Declaration of globals in header file Jorgen Grahn <grahn+nntp@snipabacken.se> - 2017-06-06 19:54 +0000
  Re: Style question: Declaration of globals in header file Andrey Tarasevich <andreytarasevich@hotmail.com> - 2017-06-06 18:37 -0700
    Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-07 07:54 -0700
      Re: Style question: Declaration of globals in header file David Brown <david.brown@hesbynett.no> - 2017-06-07 17:23 +0200
        Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-07 11:10 -0700
          Re: Style question: Declaration of globals in header file David Brown <david.brown@hesbynett.no> - 2017-06-07 22:13 +0200
            Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-07 14:57 -0700
              Re: Style question: Declaration of globals in header file David Brown <david.brown@hesbynett.no> - 2017-06-08 00:05 +0200
              Re: Style question: Declaration of globals in header file bartc <bc@freeuk.com> - 2017-06-07 23:19 +0100
                Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-07 16:16 -0700
              Re: Style question: Declaration of globals in header file Ian Collins <ian-news@hotmail.com> - 2017-06-08 12:56 +1200
                Re: Style question: Declaration of globals in header file David Brown <david.brown@hesbynett.no> - 2017-06-08 08:51 +0200
                Re: Style question: Declaration of globals in header file David Thompson <dave.thompson2@verizon.net> - 2017-07-09 22:43 -0400
                Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-07-10 08:46 -0700
                Re: Style question: Declaration of globals in header file Robert Wessel <robertwessel2@yahoo.com> - 2017-07-10 21:00 -0500
                Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-07-10 21:08 -0700
                Re: Style question: Declaration of globals in header file Robert Wessel <robertwessel2@yahoo.com> - 2017-07-11 01:18 -0500
                Re: Style question: Declaration of globals in header file bartc <bc@freeuk.com> - 2017-06-08 10:10 +0100
                Re: Style question: Declaration of globals in header file raltbos@xs4all.nl (Richard Bos) - 2017-06-17 18:08 +0000
            Re: Style question: Declaration of globals in header file "Patrick.Schluter" <Patrick.Schluter@free.fr> - 2017-06-10 08:36 +0200
    Re: Style question: Declaration of globals in header file Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-09 10:09 -0700
      Re: Style question: Declaration of globals in header file supercat@casperkitty.com - 2017-06-09 12:17 -0700
  Re: Style question: Declaration of globals in header file Tim Rentsch <txr@alumni.caltech.edu> - 2017-06-09 09:52 -0700

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