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Re: extern array as a pointer

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From Keith Thompson <kst-u@mib.org>
Newsgroups comp.lang.c
Subject Re: extern array as a pointer
Date Tue, 12 Jul 2016 09:30:56 -0700
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Frank Tetzel <s1445051@mail.zih.tu-dresden.de> writes:
[...]
> But why? Why is "extern int *array" containing the first element which
> is 0? Why doesn't the compiler or rather the linker warn about this? Is
> the type information lost for the linker?

Yes, that's exactly the problem: the linker is required to pay attention
to type information.

Careful use of header files, so you don't have multiple unchecked
declarations of the same thing, can avoid problems like this.

> In the past i used *array and array[] interchangeable. I might have to
> reconsider that.

Please do.  And read section 6 of the comp.lang.c FAQ:

http://www.c-faq.com/

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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extern array as a pointer sinbad <sinbad.sinbad@gmail.com> - 2016-07-12 03:06 -0700
  Re: extern array as a pointer BartC <bc@freeuk.com> - 2016-07-12 11:45 +0100
    Re: extern array as a pointer Frank Tetzel <s1445051@mail.zih.tu-dresden.de> - 2016-07-12 13:58 +0200
      Re: extern array as a pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-12 13:33 +0100
      Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:30 -0700
        Re: extern array as a pointer James Kuyper <jameskuyper@verizon.net> - 2016-07-12 12:52 -0400
          Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 11:30 -0700
            Re: extern array as a pointer supercat@casperkitty.com - 2016-07-12 11:51 -0700
        Re: extern array as a pointer supercat@casperkitty.com - 2016-07-12 10:55 -0700
    Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:28 -0700
  Re: extern array as a pointer Nobody <nobody@nowhere.invalid> - 2016-07-12 13:26 +0100
    Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:26 -0700
  Re: extern array as a pointer Richard Heathfield <rjh@cpax.org.uk> - 2016-07-12 13:46 +0100
  Re: extern array as a pointer James Kuyper <jameskuyper@verizon.net> - 2016-07-12 12:33 -0400

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