huge_vall.h 1.5 KB

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  1. /* `HUGE_VALL' constant for m68k (where it is infinity).
  2. Used by <stdlib.h> and <math.h> functions for overflow.
  3. Copyright (C) 1992, 1995, 1996, 1997, 1999, 2000, 2004
  4. Free Software Foundation, Inc.
  5. This file is part of the GNU C Library.
  6. The GNU C Library is free software; you can redistribute it and/or
  7. modify it under the terms of the GNU Lesser General Public
  8. License as published by the Free Software Foundation; either
  9. version 2.1 of the License, or (at your option) any later version.
  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. You should have received a copy of the GNU Lesser General Public
  15. License along with the GNU C Library; if not, see
  16. <http://www.gnu.org/licenses/>. */
  17. #ifndef _MATH_H
  18. # error "Never use <bits/huge_val.h> directly; include <math.h> instead."
  19. #endif
  20. #if __GNUC_PREREQ(3,3)
  21. # define HUGE_VALL (__builtin_huge_vall ())
  22. #elif __GNUC_PREREQ(2,96)
  23. # define HUGE_VALL (__extension__ 0x1.0p32767L)
  24. #elif defined __GNUC__
  25. # define HUGE_VALL \
  26. (__extension__ \
  27. ((union { unsigned long __l[3]; long double __ld; }) \
  28. { __l: { 0x7fff0000UL, 0x80000000UL, 0UL } }).__ld)
  29. #else /* not GCC */
  30. static union { unsigned char __c[12]; long double __ld; } __huge_vall =
  31. { { 0x7f, 0xff, 0, 0, 0x80, 0, 0, 0, 0, 0, 0, 0 } };
  32. # define HUGE_VALL (__huge_vall.__ld)
  33. #endif /* GCC 2.95. */