1 files changed, 4 insertions, 0 deletions
diff --git a/includes.h b/includes.h
index 4740418a..633fd960 100644
--- a/includes.h
+++ b/includes.h
@@ -103,4 +103,8 @@ static /**/const char *const rcsid[] = { (char *)rcsid, "\100(#)" msg }
 #include "openbsd-compat/bsd-cygwin_util.h"
 #include "entropy.h"
 
+#ifndef MAP_FAILED
+# define MAP_FAILED ((void *)-1)
+#endif
+
 #endif /* INCLUDES_H */