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diff --git a/sysdeps/generic/pow.c b/sysdeps/generic/pow.c
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+/*
+ * Copyright (c) 1985, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)pow.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint */
+
+/* POW(X,Y)  
+ * RETURN X**Y 
+ * DOUBLE PRECISION (VAX D format 56 bits, IEEE DOUBLE 53 BITS)
+ * CODED IN C BY K.C. NG, 1/8/85; 
+ * REVISED BY K.C. NG on 7/10/85.
+ * KERNEL pow_P() REPLACED BY P. McILROY 7/22/92.
+ * Required system supported functions:
+ *      scalb(x,n)      
+ *      logb(x)         
+ *	copysign(x,y)	
+ *	finite(x)	
+ *	drem(x,y)
+ *
+ * Required kernel functions:
+ *	exp__D(a,c)			exp(a + c) for |a| << |c|
+ *	struct d_double dlog(x)		r.a + r.b, |r.b| < |r.a|
+ *
+ * Method
+ *	1. Compute and return log(x) in three pieces:
+ *		log(x) = n*ln2 + hi + lo,
+ *	   where n is an integer.
+ *	2. Perform y*log(x) by simulating muti-precision arithmetic and 
+ *	   return the answer in three pieces:
+ *		y*log(x) = m*ln2 + hi + lo,
+ *	   where m is an integer.
+ *	3. Return x**y = exp(y*log(x))
+ *		= 2^m * ( exp(hi+lo) ).
+ *
+ * Special cases:
+ *	(anything) ** 0  is 1 ;
+ *	(anything) ** 1  is itself;
+ *	(anything) ** NaN is NaN;
+ *	NaN ** (anything except 0) is NaN;
+ *	+(anything > 1) ** +INF is +INF;
+ *	-(anything > 1) ** +INF is NaN;
+ *	+-(anything > 1) ** -INF is +0;
+ *	+-(anything < 1) ** +INF is +0;
+ *	+(anything < 1) ** -INF is +INF;
+ *	-(anything < 1) ** -INF is NaN;
+ *	+-1 ** +-INF is NaN and signal INVALID;
+ *	+0 ** +(anything except 0, NaN)  is +0;
+ *	-0 ** +(anything except 0, NaN, odd integer)  is +0;
+ *	+0 ** -(anything except 0, NaN)  is +INF and signal DIV-BY-ZERO;
+ *	-0 ** -(anything except 0, NaN, odd integer)  is +INF with signal;
+ *	-0 ** (odd integer) = -( +0 ** (odd integer) );
+ *	+INF ** +(anything except 0,NaN) is +INF;
+ *	+INF ** -(anything except 0,NaN) is +0;
+ *	-INF ** (odd integer) = -( +INF ** (odd integer) );
+ *	-INF ** (even integer) = ( +INF ** (even integer) );
+ *	-INF ** -(anything except integer,NaN) is NaN with signal;
+ *	-(x=anything) ** (k=integer) is (-1)**k * (x ** k);
+ *	-(anything except 0) ** (non-integer) is NaN with signal;
+ *
+ * Accuracy:
+ *	pow(x,y) returns x**y nearly rounded. In particular, on a SUN, a VAX,
+ *	and a Zilog Z8000,
+ *			pow(integer,integer)
+ *	always returns the correct integer provided it is representable.
+ *	In a test run with 100,000 random arguments with 0 < x, y < 20.0
+ *	on a VAX, the maximum observed error was 1.79 ulps (units in the 
+ *	last place).
+ *
+ * Constants :
+ * The hexadecimal values are the intended ones for the following constants.
+ * The decimal values may be used, provided that the compiler will convert
+ * from decimal to binary accurately enough to produce the hexadecimal values
+ * shown.
+ */
+
+#include <errno.h>
+#include <math.h>
+
+#include "mathimpl.h"
+
+#if (defined(vax) || defined(tahoe))
+#define TRUNC(x)	x = (double) (float) x
+#define _IEEE		0
+#else
+#define _IEEE		1
+#define endian		(((*(int *) &one)) ? 1 : 0)
+#define TRUNC(x) 	*(((int *) &x)+endian) &= 0xf8000000
+#define infnan(x)	0.0
+#endif		/* vax or tahoe */
+
+const static double zero=0.0, one=1.0, two=2.0, negone= -1.0;
+
+static double pow_P __P((double, double));
+
+double pow(x,y)  	
+double x,y;
+{
+	double t;
+	if (y==zero)
+		return (one);
+	else if (y==one || (_IEEE && x != x))
+		return (x);		/* if x is NaN or y=1 */
+	else if (_IEEE && y!=y)		/* if y is NaN */
+		return (y);
+	else if (!finite(y))		/* if y is INF */
+		if ((t=fabs(x))==one)	/* +-1 ** +-INF is NaN */
+			return (y - y);
+		else if (t>one)
+			return ((y<0)? zero : ((x<zero)? y-y : y));
+		else
+			return ((y>0)? zero : ((x<0)? y-y : -y));
+	else if (y==two)
+		return (x*x);
+	else if (y==negone)
+		return (one/x);
+    /* x > 0, x == +0 */
+	else if (copysign(one, x) == one)
+		return (pow_P(x, y));
+
+    /* sign(x)= -1 */
+	/* if y is an even integer */
+	else if ( (t=drem(y,two)) == zero)
+		return (pow_P(-x, y));
+
+	/* if y is an odd integer */
+	else if (copysign(t,one) == one)
+		return (-pow_P(-x, y));
+
+	/* Henceforth y is not an integer */
+	else if (x==zero)	/* x is -0 */
+		return ((y>zero)? -x : one/(-x));
+	else if (_IEEE)
+		return (zero/zero);
+	else
+		return (infnan(EDOM));
+}
+/* kernel function for x >= 0 */
+static double
+#ifdef _ANSI_SOURCE
+pow_P(double x, double y)
+#else
+pow_P(x, y) double x, y;
+#endif
+{
+	struct Double s, t, __log__D();
+	double  __exp__D(), huge = 1e300, tiny = 1e-300;
+
+	if (x == zero)
+		if (y > zero)
+			return (zero);
+		else if (_IEEE)
+			return (huge*huge);
+		else
+			return (infnan(ERANGE));
+	if (x == one)
+		return (one);
+	if (!finite(x))
+		if (y < zero)
+			return (zero);
+		else if (_IEEE)
+			return (huge*huge);
+		else
+			return (infnan(ERANGE));
+	if (y >= 7e18)		/* infinity */
+		if (x < 1)
+			return(tiny*tiny);
+		else if (_IEEE)
+			return (huge*huge);
+		else
+			return (infnan(ERANGE));
+
+	/* Return exp(y*log(x)), using simulated extended */
+	/* precision for the log and the multiply.	  */
+
+	s = __log__D(x);
+	t.a = y;
+	TRUNC(t.a);
+	t.b = y - t.a;
+	t.b = s.b*y + t.b*s.a;
+	t.a *= s.a;
+	s.a = t.a + t.b;
+	s.b = (t.a - s.a) + t.b;
+	return (__exp__D(s.a, s.b));
+}