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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"