Re: double exclamation (!!) suckage in the kernel

["Satyam Sharma" <satyam.sharma@gmail.com>]

On 5/26/07, Satyam Sharma <satyam.sharma@gmail.com> wrote:
> On 5/26/07, Al Viro <viro@ftp.linux.org.uk> wrote:
> >
> > That's a question for a quiz in introductory course on C:
>
> Ugh ... ok, I've embarrassed myself publicly already, so I'll
> also be brave enough to take a C quiz here :-)

Hmmm, and now I seem to have flunked ...

> >         what type should x have for !!x to be a valid expression?
>
> Any integer type (includes pointers)

gcc doesn't seem to mind a ! on a float either (does it do an implicit
cast to int first?). Can't think of too many situations where one would
want to do a ! on a float, actually, in any case ...

> >         what will be the type of result?
>
> int (I guess boolean for C99?)