diff --git a/Modules/_hashopenssl.c b/Modules/_hashopenssl.c
index a3fb052..9bdd274 100644
--- a/Modules/_hashopenssl.c
+++ b/Modules/_hashopenssl.c
@@ -18,6 +18,10 @@
 #include <openssl/evp.h>
 
 
+#ifndef HASH_OBJ_CONSTRUCTOR
+#define HASH_OBJ_CONSTRUCTOR 0
+#endif
+
 typedef struct {
     PyObject_HEAD
     PyObject            *name;  /* name of this hash algorithm */