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diff --git a/gnulib/lib/rint.c b/gnulib/lib/rint.c
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+/* Round according to the current rounding mode.
+ Copyright (C) 2007, 2010-2011 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#if ! defined USE_LONG_DOUBLE
+# include <config.h>
+#endif
+
+/* Specification. */
+#include <math.h>
+
+#include <float.h>
+#include <stdlib.h>
+
+#undef MIN
+
+#ifdef USE_LONG_DOUBLE
+# define RINT rintl
+# define DOUBLE long double
+# define MANT_DIG LDBL_MANT_DIG
+# define MIN LDBL_MIN
+# define L_(literal) literal##L
+#elif ! defined USE_FLOAT
+# define RINT rint
+# define DOUBLE double
+# define MANT_DIG DBL_MANT_DIG
+# define MIN DBL_MIN
+# define L_(literal) literal
+#else /* defined USE_FLOAT */
+# define RINT rintf
+# define DOUBLE float
+# define MANT_DIG FLT_MANT_DIG
+# define MIN FLT_MIN
+# define L_(literal) literal##f
+#endif
+
+/* -0.0. See minus-zero.h. */
+#if defined __hpux || defined __sgi || defined __ICC
+# define MINUS_ZERO (-MIN * MIN)
+#else
+# define MINUS_ZERO L_(-0.0)
+#endif
+
+DOUBLE
+RINT (DOUBLE x)
+{
+ /* 2^(MANT_DIG-1). */
+ static const DOUBLE TWO_MANT_DIG =
+ /* Assume MANT_DIG <= 5 * 31.
+ Use the identity
+ n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */
+ (DOUBLE) (1U << ((MANT_DIG - 1) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 1) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 2) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 3) / 5))
+ * (DOUBLE) (1U << ((MANT_DIG - 1 + 4) / 5));
+
+ /* The use of 'volatile' guarantees that excess precision bits are dropped at
+ each addition step and before the following comparison at the caller's
+ site. It is necessary on x86 systems where double-floats are not IEEE
+ compliant by default, to avoid that the results become platform and
+ compiler option dependent. 'volatile' is a portable alternative to gcc's
+ -ffloat-store option. */
+ volatile DOUBLE z = x;
+
+ /* Consider the current rounding mode, cf.
+ <http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/float.h.html>.
+ This implementation supports only rounds-to-nearest. */
+ if (FLT_ROUNDS != 1)
+ abort ();
+
+ if (z > L_(0.0))
+ {
+ /* Avoid rounding error for x = 0.5 - 2^(-MANT_DIG-1). */
+ if (z < L_(0.5))
+ z = L_(0.0);
+ /* Avoid rounding errors for values near 2^k, where k >= MANT_DIG-1. */
+ else if (z < TWO_MANT_DIG)
+ {
+ /* Round to the next integer. */
+ z += TWO_MANT_DIG;
+ z -= TWO_MANT_DIG;
+ }
+ }
+ else if (z < L_(0.0))
+ {
+ /* Avoid rounding error for x = -(0.5 - 2^(-MANT_DIG-1)). */
+ if (z > - L_(0.5))
+ z = MINUS_ZERO;
+ /* Avoid rounding errors for values near -2^k, where k >= MANT_DIG-1. */
+ else if (z > -TWO_MANT_DIG)
+ {
+ /* Round to the next integer. */
+ z -= TWO_MANT_DIG;
+ z += TWO_MANT_DIG;
+ }
+ }
+ return z;
+}