what's the two !! usage?
baumann.Pan_at_gmail.com
Date: 03/30/05
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Date: 29 Mar 2005 17:52:48 -0800
hi all,
in the linux kernel code compiler.h
i read
#define likely(x) __builtin_expect(!!(x), 1)
#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
#define __builtin_expect(exp,c) (exp)
#endif
what's the meaing of !!(x)?
thanks
baumann@pan
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