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-rw-r--r--math/w_tgamma.c54
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diff --git a/math/w_tgamma.c b/math/w_tgamma.c
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+/* @(#)w_gamma.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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: w_gamma.c,v 1.7 1995/11/20 22:06:43 jtc Exp $";
+#endif
+
+/* double gamma(double x)
+ * Return  the logarithm of the Gamma function of x or the Gamma function of x,
+ * depending on the library mode.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+	double __tgamma(double x)
+#else
+	double __tgamma(x)
+	double x;
+#endif
+{
+        double y;
+	int local_signgam;
+	y = __ieee754_gamma_r(x,&local_signgam);
+	if (local_signgam < 0) y = -y;
+#ifdef _IEEE_LIBM
+	return y;
+#else
+	if(_LIB_VERSION == _IEEE_) return y;
+
+	if(!__finite(y)&&__finite(x)) {
+	  if(__floor(x)==x&&x<=0.0)
+	    return __kernel_standard(x,x,41); /* tgamma pole */
+	  else
+	    return __kernel_standard(x,x,40); /* tgamma overflow */
+	}
+	return y;
+#endif
+}
+weak_alias (__tgamma, tgamma)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__tgamma, __tgammal)
+weak_alias (__tgamma, tgammal)
+#endif