1: /* Default `INFINITY' constant.
    2:    Copyright (C) 2004 Free Software Foundation, Inc.
    3:    This file is part of the GNU C Library.
    4: 
    5:    The GNU C Library is free software; you can redistribute it and/or
    6:    modify it under the terms of the GNU Lesser General Public
    7:    License as published by the Free Software Foundation; either
    8:    version 2.1 of the License, or (at your option) any later version.
    9: 
   10:    The GNU C Library is distributed in the hope that it will be useful,
   11:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   12:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   13:    Lesser General Public License for more details.
   14: 
   15:    You should have received a copy of the GNU Lesser General Public
   16:    License along with the GNU C Library; if not, write to the Free
   17:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   18:    02111-1307 USA.  */
   19: 
   20: #ifndef _MATH_H
   21: # error "Never use <bits/inf.h> directly; include <math.h> instead."
   22: #endif
   23: 
   24: /* If we don't have real infinity, then we're supposed to produce a float
   25:    value that overflows at translation time, which is required to produce
   26:    a diagnostic.  GCC's __builtin_inff produces a quite nice diagnostic
   27:    that tells the user that the target doesn't support infinities.  */
   28: 
   29: #if __GNUC_PREREQ(3,3)
   30: # define INFINITY       (__builtin_inff())
   31: #else
   32: # define INFINITY       (1e9999f)
   33: #endif