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diff --git a/lib/libm/src/s_casinf.c b/lib/libm/src/s_casinf.c
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+/*	$OpenBSD: s_casinf.c,v 1.1 2008/09/07 20:36:09 martynas Exp $	*/
+/*
+ * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*							casinf()
+ *
+ *	Complex circular arc sine
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * void casinf();
+ * cmplxf z, w;
+ *
+ * casinf( &z, &w );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Inverse complex sine:
+ *
+ *                               2
+ * w = -i clog( iz + csqrt( 1 - z ) ).
+ *
+ *
+ * ACCURACY:
+ *
+ *                      Relative error:
+ * arithmetic   domain     # trials      peak         rms
+ *    IEEE      -10,+10     30000       1.1e-5      1.5e-6
+ * Larger relative error can be observed for z near zero.
+ *
+ */
+
+#include <complex.h>
+#include <math.h>
+
+float complex
+casinf(float complex z)
+{
+	float complex w;
+	float x, y;
+	static float complex ca, ct, zz, z2;
+	/*
+	float cn, n;
+	static float a, b, s, t, u, v, y2;
+	static cmplxf sum;
+	*/
+
+	x = creal(z);
+	y = cimag(z);
+
+	if(y == 0.0f) {
+		if(fabsf(x) > 1.0f) {
+			w = M_PI_2 + 0.0f * I;
+			/*mtherr( "casinf", DOMAIN );*/
+		}
+		else {
+			w = asinf (x) + 0.0f * I;
+		}
+		return (w);
+	}
+
+	/* Power series expansion */
+	/*
+	b = cabsf(z);
+	if(b < 0.125) {
+		z2.r = (x - y) * (x + y);
+		z2.i = 2.0 * x * y;
+
+		cn = 1.0;
+		n = 1.0;
+		ca.r = x;
+		ca.i = y;
+		sum.r = x;
+		sum.i = y;
+		do {
+			ct.r = z2.r * ca.r  -  z2.i * ca.i;
+			ct.i = z2.r * ca.i  +  z2.i * ca.r;
+			ca.r = ct.r;
+			ca.i = ct.i;
+
+			cn *= n;
+			n += 1.0;
+			cn /= n;
+			n += 1.0;
+			b = cn/n;
+
+			ct.r *= b;
+			ct.i *= b;
+			sum.r += ct.r;
+			sum.i += ct.i;
+			b = fabsf(ct.r) + fabsf(ct.i);
+		}
+		while(b > MACHEPF);
+		w->r = sum.r;
+		w->i = sum.i;
+		return;
+	}
+	*/
+
+
+	ca = x + y * I;
+	ct = ca * I;	/* iz */
+	/* sqrt( 1 - z*z) */
+	/* cmul( &ca, &ca, &zz ) */
+	/*x * x  -  y * y */
+	zz = (x - y) * (x + y) + (2.0f * x * y) * I;
+	zz = 1.0f - creal(zz) - cimag(zz) * I;
+	z2 = csqrtf (zz);
+
+	zz = ct + z2;
+	zz = clogf (zz);
+	/* multiply by 1/i = -i */
+	w = zz * (-1.0f * I);
+	return (w);
+}