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diff --git a/sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c b/sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c
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+/* Implementation of gamma function according to ISO C.
+   Copyright (C) 1997,1999,2002,2004,2006 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
+   		  Jakub Jelinek <jj@ultra.linux.cz, 1999.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <math.h>
+#include <math_private.h>
+
+
+long double
+__ieee754_gammal_r (long double x, int *signgamp)
+{
+  /* We don't have a real gamma implementation now.  We'll use lgamma
+     and the exp function.  But due to the required boundary
+     conditions we must check some values separately.  */
+  int64_t hx;
+  u_int64_t lx;
+
+  GET_LDOUBLE_WORDS64 (hx, lx, x);
+
+  if (((hx | lx) & 0x7fffffffffffffffLL) == 0)
+    {
+      /* Return value for x == 0 is Inf with divide by zero exception.  */
+      *signgamp = 0;
+      return 1.0 / x;
+    }
+  if (hx < 0 && (u_int64_t) hx < 0xfff0000000000000ULL && __rintl (x) == x)
+    {
+      /* Return value for integer x < 0 is NaN with invalid exception.  */
+      *signgamp = 0;
+      return (x - x) / (x - x);
+    }
+  if (hx == 0xfff0000000000000ULL)
+    {
+      /* x == -Inf.  According to ISO this is NaN.  */
+      *signgamp = 0;
+      return x - x;
+    }
+
+  /* XXX FIXME.  */
+  return __ieee754_expl (__ieee754_lgammal_r (x, signgamp));
+}