diff --git a/cryptography/hazmat/backends/openssl/ssl.py b/cryptography/hazmat/backends/openssl/ssl.py
index 168d542..3af0074 100644
--- a/cryptography/hazmat/backends/openssl/ssl.py
+++ b/cryptography/hazmat/backends/openssl/ssl.py
@@ -94,7 +94,6 @@
 static const int SSL_MODE_ENABLE_PARTIAL_WRITE;
 static const int SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER;
 static const int SSL_MODE_AUTO_RETRY;
-static const int SSL_MODE_RELEASE_BUFFERS;
 static const int SSL3_RANDOM_SIZE;
 typedef ... X509_STORE_CTX;
 static const int X509_V_OK;
@@ -263,6 +262,13 @@
     SSL_CTX *,
     int (*)(const SSL *, int *, void *)) = NULL;
 #endif
+
+#ifdef SSL_MODE_RELEASE_BUFFERS
+static const int Cryptography_HAS_RELEASE_BUFFERS = 1;
+#else
+static const int Cryptography_HAS_RELEASE_BUFFERS = 0;
+const int SSL_MODE_RELEASE_BUFFERS = 0;
+#endif
 """
 
 CONDITIONAL_NAMES = {
@@ -276,5 +282,10 @@
         "SSL_set_tlsext_host_name",
         "SSL_get_servername",
         "SSL_CTX_set_tlsext_servername_callback",
-    ]
+    ],
+
+    "Cryptography_HAS_RELEASE_BUFFERS": [
+        "SSL_MODE_RELEASE_BUFFERS",
+    ],
+
 }