flt-eval-method.h 1.6 KB

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  1. /* Define __GLIBC_FLT_EVAL_METHOD.
  2. Copyright (C) 2016-2021 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <https://www.gnu.org/licenses/>. */
  15. #ifndef _MATH_H
  16. # error "Never use <bits/flt-eval-method.h> directly; include <math.h> instead."
  17. #endif
  18. /* __GLIBC_FLT_EVAL_METHOD is the value of FLT_EVAL_METHOD used to
  19. determine the evaluation method typedefs such as float_t and
  20. double_t. It must be a value from C11 or TS 18661-3:2015, and not
  21. -1. */
  22. /* In the default version of this header, follow __FLT_EVAL_METHOD__.
  23. -1 is mapped to 2 (considering evaluation as long double to be a
  24. conservatively safe assumption), and if __FLT_EVAL_METHOD__ is not
  25. defined then assume there is no excess precision and use the value
  26. 0. */
  27. #ifdef __FLT_EVAL_METHOD__
  28. # if __FLT_EVAL_METHOD__ == -1
  29. # define __GLIBC_FLT_EVAL_METHOD 2
  30. # else
  31. # define __GLIBC_FLT_EVAL_METHOD __FLT_EVAL_METHOD__
  32. # endif
  33. #else
  34. # define __GLIBC_FLT_EVAL_METHOD 0
  35. #endif