From mboxrd@z Thu Jan  1 00:00:00 1970
From: fthain@telegraphics.com.au (Finn Thain)
Date: Wed, 19 Mar 2014 12:46:16 +1100 (EST)
Subject: [PATCH 00/12] scsi/NCR5380: fix debugging macros and #include
 structure
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To: linux-arm-kernel@lists.infradead.org
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On Tue, 18 Mar 2014, Joe Perches wrote:

> But using "if (0)" prevents the no_printk from occurring at all so there 
> would be no side-effects and the format & args would still be verified 
> by the compiler.

I'd prefer this (for symmetry and clarity):

#if NDEBUG
#define dprintk(flg, fmt, ...) \
        do { if ((NDEBUG) & (flg)) pr_debug(fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintk(flg, fmt, ...) \
        do { if (0) pr_debug(fmt, ## __VA_ARGS__); } while (0)
#endif

But you seem to be asking for this instead:

#if NDEBUG
#define dprintk(flg, fmt, ...) \
        do { if ((NDEBUG) & (flg)) pr_debug(fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintk(flg, fmt, ...) \
        do { if (0) no_printk(fmt, ## __VA_ARGS__); } while (0)
#endif

Why is that better?

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