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-rw-r--r--math/w_lgamma.c60
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diff --git a/math/w_lgamma.c b/math/w_lgamma.c
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+/* @(#)w_lgamma.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_lgamma.c,v 1.6 1995/05/10 20:49:24 jtc Exp $";
+#endif
+
+/* double lgamma(double x)
+ * Return the logarithm of the Gamma function of x.
+ *
+ * Method: call __ieee754_lgamma_r
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+#ifdef __STDC__
+	double __lgamma(double x)
+#else
+	double __lgamma(x)
+	double x;
+#endif
+{
+#ifdef _IEEE_LIBM
+	return __ieee754_lgamma_r(x,&signgam);
+#else
+        double y;
+	int local_signgam = 0;
+        y = __ieee754_lgamma_r(x,&local_signgam);
+	if (_LIB_VERSION != _ISOC_)
+	  /* ISO C99 does not define the global variable.  */
+	  signgam = local_signgam;
+        if(_LIB_VERSION == _IEEE_) return y;
+        if(!__finite(y)&&__finite(x)) {
+            if(__floor(x)==x&&x<=0.0)
+                return __kernel_standard(x,x,15); /* lgamma pole */
+            else
+                return __kernel_standard(x,x,14); /* lgamma overflow */
+        } else
+            return y;
+#endif
+}
+weak_alias (__lgamma, lgamma)
+strong_alias (__lgamma, __gamma)
+weak_alias (__gamma, gamma)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__lgamma, __lgammal)
+weak_alias (__lgamma, lgammal)
+strong_alias (__gamma, __gammal)
+weak_alias (__gamma, gammal)
+#endif