From: Denis Vlasenko <vda@ilport.com.ua>
To: "colin" <colin@realtek.com.tw>
Subject: Re: CONFIG_PRINTK doesn't makes size smaller
Date: Tue, 20 Sep 2005 11:30:10 +0300
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On Tuesday 20 September 2005 09:14, colin wrote:
> 
> Hi there,
> I tried to make kernel with CONFIG_PRINTK off. I considered it should become
> smaller, but it didn't because it actually isn't an empty function, and
> there are many copies of it in vmlinux, not just one. Here is its
> definition:
>     static inline int printk(const char *s, ...) { return 0; }
> 
> I change the definition to this and it can greatly reduce the size by about
> 5%:
>     #define printk(...) do {} while (0)
> However, this definition would lead to error in some situations. For
> example:
>     1. (printk)
>     2. ret = printk
> 
> I hope someone could suggest a better definition of printk that can both
> make printk smaller and eliminate errors.

I think isolated testcase (a preprocessed .c file) would be interesting.
Use make dir/dir/file.i, reduce result to small .c file which shows
the problem, and show it on lkml.
--
vda
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