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diff --git a/sysdeps/m68k/s_isinfl.c b/sysdeps/m68k/s_isinfl.c
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+/* Copyright (C) 1991, 1992, 1995, 1997, 2002 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 <math.h>
+#include "ieee754.h"
+
+/* Return 0 if VALUE is finite or NaN, +1 if it
+   is +Infinity, -1 if it is -Infinity.  */
+int
+__isinfl (long double value)
+{
+  union ieee854_long_double u;
+
+  u.d = value;
+
+  /* An IEEE 854 infinity has an exponent with the
+     maximum possible value and a zero mantissa.
+     In Motorola's interpretation the integer bit is ignored.  */
+  if ((u.ieee.exponent & 0x7fff) == 0x7fff &&
+      (u.ieee.mantissa0 & 0x7fffffff) == 0 && u.ieee.mantissa1 == 0)
+    return u.ieee.negative ? -1 : 1;
+
+  return 0;
+}
+
+hidden_def (__isinfl)
+weak_alias (__isinfl, isinfl);