1 files changed, 1 insertions, 0 deletions

diff --git a/fmacros.h b/fmacros.h
index 4cdbc13..f6a6d7d 100644
--- a/fmacros.h
+++ b/fmacros.h
@@ -7,6 +7,7 @@
 #endif
 
 #if defined(__CYGWIN__)
+#define _POSIX_C_SOURCE 200112L
 #include <sys/cdefs.h>
 #endif