[patch,fortran] Handle (signed) zeros, infinities and NaNs in some intrinsics

[Steve Kargl]

On Sat, Oct 11, 2014 at 03:13:00PM +0200, FX wrote:
> The attached patch fixes the compile-time simplification of special
> values (positive and negative zeros, infinities, and NaNs) in
> intrinsics EXPONENT, FRACTION, RRSPACING, SET_EXPONENT, SPACING.
> Those are all the intrinsics in the Fortran 2008 standard that say
> anything about these special values, so it makes sense to fix them.
> This is the compile-time part of PR 48979
> (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48979).
> 

Looks ok to me.

-- 
Steve