Messages in this thread | | | Date | Fri, 25 May 2007 22:32:13 +0100 | From | Al Viro <> | Subject | Re: double exclamation (!!) suckage in the kernel |
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On Sat, May 26, 2007 at 02:26:11AM +0530, Satyam Sharma wrote: > also be brave enough to take a C quiz here :-) > > > what type should x have for !!x to be a valid expression? > > Any integer type (includes pointers)
Er, no... Pointers are not integer types *and* you can use ! on any scalar type (including floating ones, even though it's not particulary useful there).
> > what will be the type of result? > > int (I guess boolean for C99?)
Actually, ! and comparisons still give int in C99 (and !x is defined as (x == 0) in all situations). - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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