Eric Blake asked:
> For that matter, isnan() is specified to be a macro, not a function. On
> what platforms does the macro in the system <math.h> truly rely on a libm
> function?
On AIX, OSF/1, HP-UX:
AIX 4.3.2: isnan() is a function, defined in libm
OSF/1 4.0d: isnan() is a function, defined in libm
HP-UX 11.00: isnan() is a macro, dispatching to _Isnanf, isnan, _Isnanf80,
the first two being defined in libm.
Solaris 10: isnan() is a function, defined in libc
Cygwin: isnan() is a function, defined in cygwin.dll
Bruno
