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Date: Wed, 02 Jan 2002 23:56:25 -0800
From: Andrew Morton <akpm@zip.com.au>
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To: "H . J . Lu" <hjl@lucon.org>
CC: Momchil Velikov <velco@fadata.bg>, Oliver Xymoron <oxymoron@waste.org>,
        vda <vda@port.imtp.ilyichevsk.odessa.ua>, linux-kernel@vger.kernel.org
Subject: Re: Extern variables in *.c files
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"H . J . Lu" wrote:
> 
> ...
> Compile doesn't emit the size info for
> 
> extern char a;

You're right.  I goofed.
 
> One way to fix it is to remove
> 
> extern char a;
> 
> and put
> 
> extern int a;
> 
> in a header file which is included by everyone.
> 

Yup.  Problem is, we have about 1500 instances in the kernel :(

(Wouldn't it be nice if `int a;' generated a compiler error
if a declaration `extern int a;' was not in scope?)

Oh well.  Seems that disabling -fno-common and enabling
--warn-common is the only way to autodetect bugs such as this.

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