fclrexcpt.c

来自「linux下的C语言库源码有一百多M解压后很不错」· C语言 代码 · 共 49 行

/* Clear given exceptions in current floating-point environment.
   Copyright (C) 1997,99,2000,01 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <fenv_libc.h>

#undef feclearexcept
int
__feclearexcept (int excepts)
{
  fenv_union_t u;

  /* Get the current state.  */
  u.fenv = fegetenv_register ();

  /* Clear the relevant bits.  */
  u.l[1] = u.l[1] & ~((-(excepts >> (31 - FPSCR_VX) & 1) & FE_ALL_INVALID)
		      | (excepts & FPSCR_STICKY_BITS));

  /* Put the new state in effect.  */
  fesetenv_register (u.fenv);

  /* Success.  */
  return 0;
}

#include <shlib-compat.h>
#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
strong_alias (__feclearexcept, __old_feclearexcept)
compat_symbol (libm, __old_feclearexcept, feclearexcept, GLIBC_2_1);
#endif

versioned_symbol (libm, __feclearexcept, feclearexcept, GLIBC_2_2);