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diff --git a/newlib/libm/mathfp/e_atanh.c b/newlib/libm/mathfp/e_atanh.c
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+++ b/newlib/libm/mathfp/e_atanh.c
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+
+/* @(#)e_atanh.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice 
+ * is preserved.
+ * ====================================================
+ *
+ */
+
+/*
+FUNCTION
+        <<atanh>>, <<atanhf>>---inverse hyperbolic tangent
+
+INDEX
+        atanh
+INDEX
+        atanhf
+
+ANSI_SYNOPSIS
+        #include <math.h>
+        double atanh(double <[x]>);
+        float atanhf(float <[x]>);
+
+TRAD_SYNOPSIS
+        #include <math.h>
+        double atanh(<[x]>)
+        double <[x]>;
+
+        float atanhf(<[x]>)
+        float <[x]>;
+
+DESCRIPTION
+        <<atanh>> calculates the inverse hyperbolic tangent of <[x]>.
+
+        <<atanhf>> is identical, other than taking and returning
+        <<float>> values.
+
+RETURNS
+        <<atanh>> and <<atanhf>> return the calculated value.
+
+        If
+        @ifinfo
+        |<[x]>|
+        @end ifinfo
+        @tex
+        $|x|$
+        @end tex
+        is greater than 1, the global <<errno>> is set to <<EDOM>> and
+        the result is a NaN.  A <<DOMAIN error>> is reported.
+
+        If
+        @ifinfo
+        |<[x]>|
+        @end ifinfo
+        @tex
+        $|x|$
+        @end tex
+        is 1, the global <<errno>> is set to <<EDOM>>; and the result is
+        infinity with the same sign as <<x>>.  A <<SING error>> is reported.
+
+        You can modify the error handling for these routines using
+        <<matherr>>.
+
+PORTABILITY
+        Neither <<atanh>> nor <<atanhf>> are ANSI C.
+
+QUICKREF
+        atanh - pure
+        atanhf - pure
+
+
+*/
+
+/* atanh(x)
+ * Method :
+ *    1.Reduced x to positive by atanh(-x) = -atanh(x)
+ *    2.For x>=0.5
+ *                  1              2x                          x
+ *	atanh(x) = --- * log(1 + -------) = 0.5 * log1p(2 * --------)
+ *                  2             1 - x                      1 - x
+ *	
+ * 	For x<0.5
+ *	atanh(x) = 0.5*log1p(2x+2x*x/(1-x))
+ *
+ * Special cases:
+ *	atanh(x) is NaN if |x| > 1 with signal;
+ *	atanh(NaN) is that NaN with no signal;
+ *	atanh(+-1) is +-INF with signal.
+ *
+ */
+
+#include "fdlibm.h"
+
+#ifndef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+static const double one = 1.0, huge = 1e300;
+#else
+static double one = 1.0, huge = 1e300;
+#endif
+
+#ifdef __STDC__
+static const double zero = 0.0;
+#else
+static double zero = 0.0;
+#endif
+
+#ifdef __STDC__
+	double atanh(double x)
+#else
+	double atanh(x)
+	double x;
+#endif
+{
+	double t;
+	__int32_t hx,ix;
+	__uint32_t lx;
+	EXTRACT_WORDS(hx,lx,x);
+	ix = hx&0x7fffffff;
+	if ((ix|((lx|(-lx))>>31))>0x3ff00000) /* |x|>1 */
+	    return (x-x)/(x-x);
+	if(ix==0x3ff00000) 
+	    return x/zero;
+	if(ix<0x3e300000&&(huge+x)>zero) return x;	/* x<2**-28 */
+	SET_HIGH_WORD(x,ix);
+	if(ix<0x3fe00000) {		/* x < 0.5 */
+	    t = x+x;
+	    t = 0.5*log1p(t+t*x/(one-x));
+	} else 
+	    t = 0.5*log1p((x+x)/(one-x));
+	if(hx>=0) return t; else return -t;
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */