From resolution of https://code.google.com/p/ttf2eot/issues/detail?id=26

--- ttf2eot-0.0.2-2/OpenTypeUtilities.cpp	2009-04-30 04:18:46.000000000 -0500
+++ ttf2eot-0.0.2-2/OpenTypeUtilities.cpp	2016-03-31 01:06:39.109996011 -0500
@@ -25,6 +25,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
  */
 
+#include <cstddef>
 #include <string.h>
 #include <vector>
 
