Re: [PATCH 00/12] scsi/NCR5380: fix debugging macros and #include structure

[Joe Perches]

On Tue, 2014-03-18 at 13:55 +0100, Geert Uytterhoeven wrote:
> On Tue, Mar 18, 2014 at 1:45 PM, Joe Perches <joe@xxxxxxxxxxx> wrote:

Hi Geert.

> > #define dprintk(flg, fmt, ...) \
> > do { if (0) pr_debug(fmt, ##__VA_ARGS__); } while (0)
> 
> Na, no_printk():
> 
> #define dprintk(flg, fmt, ...) no_printk(fmt, ##__VA_ARGS__)

Fine, but with a correction.

no_printk keeps all side effects like
performing any function calls made by the
statement or accessing any volatiles.

Using

do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)

does not have any side-effects.


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