diff --git a/osdep-cygwin.c b/osdep-cygwin.c
index f3a9042..15ca23c 100644
--- a/osdep-cygwin.c
+++ b/osdep-cygwin.c
@@ -16,6 +16,7 @@
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <sys/param.h>
 #include <sys/types.h>
 #include <sys/stat.h>