view tests/nan.h @ 17364:7524d97ae56f

stdalign: port to stricter ISO C11 ISO C11 says that _Alignof's operand must be a parenthesized type. Problem reported by Eli Zaretskii in <http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00960.html>. * doc/posix-headers/stdalign.texi (stdalign.h): Document this. * m4/stdalign.m4 (gl_STDALIGN_H): Don't use _Alignof (expr).
author Paul Eggert <eggert@cs.ucla.edu>
date Fri, 29 Mar 2013 19:47:13 -0700
parents e542fd46ad6f
children 344018b6e5d7
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/* Macros for not-a-number.
   Copyright (C) 2007-2013 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */


/* NaNf () returns a 'float' not-a-number.  */

/* The Compaq (ex-DEC) C 6.4 compiler and the Microsoft MSVC 9 compiler choke
   on the expression 0.0 / 0.0.  */
#if defined __DECC || defined _MSC_VER
static float
NaNf ()
{
  static float zero = 0.0f;
  return zero / zero;
}
#else
# define NaNf() (0.0f / 0.0f)
#endif


/* NaNd () returns a 'double' not-a-number.  */

/* The Compaq (ex-DEC) C 6.4 compiler and the Microsoft MSVC 9 compiler choke
   on the expression 0.0 / 0.0.  */
#if defined __DECC || defined _MSC_VER
static double
NaNd ()
{
  static double zero = 0.0;
  return zero / zero;
}
#else
# define NaNd() (0.0 / 0.0)
#endif


/* NaNl () returns a 'long double' not-a-number.  */

/* On Irix 6.5, gcc 3.4.3 can't compute compile-time NaN, and needs the
   runtime type conversion.
   The Microsoft MSVC 9 compiler chokes on the expression 0.0L / 0.0L.  */
#ifdef __sgi
static long double NaNl ()
{
  double zero = 0.0;
  return zero / zero;
}
#elif defined _MSC_VER
static long double
NaNl ()
{
  static long double zero = 0.0L;
  return zero / zero;
}
#else
# define NaNl() (0.0L / 0.0L)
#endif