Strange things in math.h under Intel OSX

Hi there,

It seems like Apple may have done some mistakes in their port
of the standard c library (which I seriously doubt). I bumped in to
this problem when I compiled
some tests for OpenEXR (under Intel OS X on a MacBook Pro). It says
that a function from math.h is invalid. As you may know, there are two
versions of some of the stuff in the std-c library, one for ppc and
the other for i386. math.h is one of them. There is a macro/function
called isnan() that determines if a float is a number or not, and it
was here I bumped into the strange things. I opened up both versions
of math.h and compared the implementation of the isnan() macro...

Here is the one in the i386 math.h:

#define isnan(x)        \
       (       sizeof (x) == sizeof(float )    ?       __isnanf(x)     \
       :       sizeof (x) == sizeof(double)    ?       __isnand(x)     \

        :       __isnan (x))

And here is the one from the ppc math.h:

#define      isnan( x )         ( ( sizeof ( (x) ) == sizeof(double) )
?           \
                             __isnand ( (double)(x) ) :
                 \
                               ( sizeof ( (x) ) == sizeof( float) ) ?
          \
                             __isnanf ( (float)(x) ) :