From: Sheng Yang <sheng@linux.intel.com>
Organization: Intel Opensource Technology Center
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] 8250: Eliminate compile warning of 8250.c
Date: Tue, 25 Nov 2008 18:51:44 +0800
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On Tuesday 25 November 2008 18:43:34 Alan Cox wrote:
> > Can't understand initializing got "risk hiding future ones". As I know,
> > didn't
>
> Because if you set it to NULL and later delete a line which does the
> intended assignment you will no longer get a warning.
>
> > think BUG_ON(n==null) cover this. And I don't think leave it to compiler
> > is more proper here.
>
> The BUG_ON covers it, the current gcc gets this right and works it out.
>
> NAK again

The logic here is strange...

If you used old compiler, you would get a warning, and you thought that's 
ensured we won't delete a intended assignment by mistake.

If you used new compiler, you wouldn't get a warning, and you think this time 
the compiler get it right.

So, what result did you expect? A warning to notice that we didn't delete a 
intended assignment, or a "right" result? 

OK. if you worry about "delete a line which does the intended assignment", the 
updated version with BUG_ON(i == NULL) can help. 

-- 
regards
Yang, Sheng

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