From: DavMac AT iname DOT com (Davin McCall)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: and another thing...
Date: Thu, 27 May 1999 04:23:54 GMT
Organization: Monash Uni
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

On Wed, 26 May 1999 11:56:59 -0500, Mark Phillips
<umphill5 AT cs DOT umanitoba DOT ca> wrote:

>
[some snipped]
>Creating: test.exe
>Error: main.o(.data+0x0):main.cc: multiple definition of 'foo'
>Error: h.o(.data+0x0):h.cc first defined here
>
>When I do this:
[at end of response]

>Shouldn't the preprocessor directives in 'header.h' handle the multiple
>declaration linking errors?

You need to use the 'extern' keyword for the variable ie.

       extern bool foo;


>love
>mark

I'm honored.  ;-)

regards,
Davin.


>
>// file #1 main.cc
>#include "header.h"
>
>int main()
>{
>   fun1();
>   return 0;
>}
>
>// file #2 h.cc
>#include "header.h"
>
>void fun1()
>{
>   foo = 1;
>}
>
>// file #3 header.h
>#ifndef HEADER_H
>#define HEADER_H
>
>void fun1();
>bool foo;
>
>#endif
>
>

__________________________________________________________
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my programming page: http://yoyo.cc.monash.edu.au/~davmac/