Re: Broken isnan(3) and/or DQNAN on Tru64

[Ludovic Courtès]

Hi,

Bruno Haible <address@hidden> writes:

>> So people compiling with GCC on this platform should pass `-mieee'
>> (`configure' could add it automatically.)
>
> The gnulib module 'fpieee' adds it automatically.

This module appears to be overzealous: `gl_FP_IEEE' just checks for the
host CPU, but on alpha*-linux-gnu, `-mieee' is apparently not needed:

--8<---------------cut here---------------start------------->8---
#include <math.h>

int
main (int argc, char *argv[])
{
  return isnan (NAN);
}
--8<---------------cut here---------------end--------------->8---

Compiled with GCC 4.2.4 on Debian GNU/Linux on Alpha, it returns 1.

Or maybe that's a Debian patch that enables `-mieee' by default?

Thanks,
Ludo'.