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diff --git a/sysdeps/libm-ieee754/s_roundf.c b/sysdeps/libm-ieee754/s_roundf.c
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+/* Round float to integer away from zero.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <math.h>
+
+#include "math_private.h"
+
+
+static const float huge = 1.0e30;
+
+
+float
+__roundf (float x)
+{
+ int32_t i0, j0;
+
+ GET_FLOAT_WORD (i0, x);
+ j0 = ((i0 >> 23) & 0xff) - 0x7f;
+ if (j0 < 23)
+ {
+ if (j0 < 0)
+ {
+ if (huge + x > 0.0F)
+ {
+ i0 &= 0x80000000;
+ if (j0 == -1)
+ i0 |= 0x3f800000;
+ }
+ }
+ else
+ {
+ u_int32_t i = 0x007fffff >> j0;
+ if ((i0 & i) == 0)
+ /* X is integral. */
+ return x;
+ if (huge + x > 0.0F)
+ {
+ /* Raise inexact if x != 0. */
+ i0 += 0x00400000 >> j0;
+ i0 &= ~i;
+ }
+ }
+ }
+ else
+ {
+ if (j0 == 0x80)
+ /* Inf or NaN. */
+ return x + x;
+ else
+ return x;
+ }
+
+ SET_FLOAT_WORD (x, i0);
+ return x;
+}
+weak_alias (__roundf, roundf)