[newlib-cygwin] Cygwin: math: Fix the return value for tgammal for zero and negative integers

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=f4e7849fa9fcd5ff0d7318f9d3d13fada6e4b317

commit f4e7849fa9fcd5ff0d7318f9d3d13fada6e4b317
Author: Martin Storsjö <martin@martin.st>
Date:   Mon Jul 29 23:48:01 2019 +0300

    Cygwin: math: Fix the return value for tgammal for zero and negative integers
    
    For zero, it should return HUGE_VAL (INFINITY), for negative integers,
    it should return NAN.
    
    Signed-off-by: Martin Storsjö <martin@martin.st>

Diff:
---
 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 99408ee..25a37ea 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