From d1ddaa8a0eca167db6669f42ff57f478500ca323 Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Mon, 8 Apr 2024 01:28:49 +0300
Subject: [PATCH] Fix Cygwin failures

---
 test/parsers_test.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/test/parsers_test.cpp b/test/parsers_test.cpp
index 8f01731..7eaaaeb 100644
--- a/test/parsers_test.cpp
+++ b/test/parsers_test.cpp
@@ -300,6 +300,10 @@ void test_config_file(const char* config_file)
     check_value(a2[6], "m1.v3", "3");
 }
 
+#if defined(__CYGWIN__)
+  extern "C" int putenv (char *__string);
+#endif
+
 void test_environment()
 {
     options_description desc;
@@ -308,7 +312,7 @@ void test_environment()
         ("bar", new untyped_value, "")
         ;
 
-#if (defined(_WIN32) && ! defined(BOOST_BORLANDC) && ! defined(BOOST_EMBTC)) || (defined(__CYGWIN__))
+#if defined(_WIN32) && ! defined(BOOST_BORLANDC) && ! defined(BOOST_EMBTC)
     _putenv("PO_TEST_FOO=1");
 #else
     putenv(const_cast<char*>("PO_TEST_FOO=1"));