Messages in this thread | | | Date | Sun, 23 Mar 2003 00:27:11 -0800 (PST) | From | Linus Torvalds <> | Subject | Re: [PATCH] parallel port |
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On Sun, 23 Mar 2003, Adrian Bunk wrote: > > > > for me. I think I complained about that once before already. Tssk, tssk. > > It's perhaps a silly question: > Why did you use a "do ... while (0)" in your fix?
I always do that (well, almost always), just because it protects macros from being mis-used.
For example, if you have
#define macro(x) ((x) = 3)
that _looks_ safe, but it allows people to write
x++ = macro(x);
or similar nonsense. So if you want a macro that always behaves like a statement (and can't be used as an expression), the "do { } while (0)" will do that.
[ The real answer is that it's so built in to my spine, that I just can't stop myself. Even if it doesn't really matter. ]
Linus
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