From f4e7849fa9fcd5ff0d7318f9d3d13fada6e4b317 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Storsj=C3=B6?= <martin@martin.st>
Date: Mon, 29 Jul 2019 23:48:01 +0300
Subject: [PATCH] Cygwin: math: Fix the return value for tgammal for zero and
 negative integers
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For zero, it should return HUGE_VAL (INFINITY), for negative integers,
it should return NAN.

Signed-off-by: Martin Storsjö <martin@martin.st>
---
 winsup/cygwin/math/tgammal.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/winsup/cygwin/math/tgammal.c b/winsup/cygwin/math/tgammal.c
index 99408eed7..25a37eaeb 100644
--- a/winsup/cygwin/math/tgammal.c
+++ b/winsup/cygwin/math/tgammal.c
@@ -285,6 +285,9 @@ long double __tgammal_r(long double x, int* sgngaml)
 		return (x);
 #endif
 #endif
+	if (x == 0.0L)
+		return copysignl(HUGE_VALL, x);
+
 	q = fabsl(x);
 
 	if (q > 13.0L)
@@ -299,8 +302,8 @@ long double __tgammal_r(long double x, int* sgngaml)
 gsing:
 				_SET_ERRNO(EDOM);
 				mtherr("tgammal", SING);
-#ifdef INFINITIES
-				return (INFINITYL);
+#ifdef NANS
+				return (NAN);
 #else
 				return (*sgngaml * MAXNUML);
 #endif