From a815d279d2d7a9deffd0161f003d54ad012cc17f Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Mon, 2 Nov 2020 23:33:13 +0100
Subject: [PATCH] enable compiling with CYGWIN signgam for lgamma is not
 available

---
 src/include/cppduals/duals/dual | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/include/cppduals/duals/dual b/src/include/cppduals/duals/dual
index 4105a1778..ab2141ea3 100644
--- a/src/include/cppduals/duals/dual
+++ b/src/include/cppduals/duals/dual
@@ -34,9 +34,11 @@
 /// Configure whether system has POSIX extern int signgam;
 #ifndef CPPDUALS_HAVE_SIGNGAM
 #ifndef _WIN32
+#ifndef __CYGWIN__
 #define CPPDUALS_HAVE_SIGNGAM 1
 #endif
 #endif
+#endif
 namespace duals {
 
 /**