Re: do { } while (0) question

From: Jiri Slaby
Date: Tue Aug 01 2006 - 04:49:51 EST

Heiko Carstens wrote:
Hi Andrew,

your commit e2c2770096b686b4d2456173f53cb50e01aa635c does this:

Always use do {} while (0). Failing to do so can cause subtle compile
failures or bugs.

-#define hotcpu_notifier(fn, pri)
-#define register_hotcpu_notifier(nb)
-#define unregister_hotcpu_notifier(nb)
+#define hotcpu_notifier(fn, pri) do { } while (0)
+#define register_hotcpu_notifier(nb) do { } while (0)
+#define unregister_hotcpu_notifier(nb) do { } while (0)

#if KILLER == 1
#define MACRO
#define MACRO do { } while (0)

if (some_condition)


How do you want to define KILLER, 0 or 1? I personally choose 0.

<a href="";>Jiri Slaby</a>
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8 22A0 32CC 55C3 39D4 7A7E
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