REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_TLSv1_0", CURL_SSLVERSION_TLSv1_0, CONST_CS|CONST_PERSISTENT);
REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_TLSv1_1", CURL_SSLVERSION_TLSv1_1, CONST_CS|CONST_PERSISTENT);
REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_TLSv1_2", CURL_SSLVERSION_TLSv1_2, CONST_CS|CONST_PERSISTENT);
+#endif
+#if PHP_HTTP_CURL_VERSION(7,52,0)
+ REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_TLSv1_3", CURL_SSLVERSION_TLSv1_3, CONST_CS|CONST_PERSISTENT);
#endif
REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_SSLv2", CURL_SSLVERSION_SSLv2, CONST_CS|CONST_PERSISTENT);
REGISTER_NS_LONG_CONSTANT("http\\Client\\Curl", "SSL_VERSION_SSLv3", CURL_SSLVERSION_SSLv3, CONST_CS|CONST_PERSISTENT);