Re: [boost] Portable signbit macro/function?

From: Peter Dimov (pdimov_at_[hidden])
Date: 2006-08-04 08:46:17

Johan Råde wrote:

> Do you think that
>
>    inline bool signbit(float x)
>    {
>        // check that signbit_mask contains at most one 1 bit
>        BOOST_ASSERT(!(signbit_mask & (signbit_mask - 1)));
>        return binary_cast<boost::uint32_t>(x) & signbit_mask;
>    }
>
> is a good idea?

The unit tests of signbit should be enough to determine whether it works on 
a particular platform.