Fixes compile error when building with OpenSSL v1.1:
contrib/epee/include/net/net_helper.h: In member function ‘void epee::net_utils::blocked_mode_client::shutdown_ssl()’:
contrib/epee/include/net/net_helper.h:579:106: error: ‘SSL_R_SHORT_READ’ was not declared in this scope
if (ec.category() == boost::asio::error::get_ssl_category() && ec.value() != ERR_PACK(ERR_LIB_SSL, 0, SSL_R_SHORT_READ))
^
contrib/epee/include/net/net_helper.h:579:106: note: suggested alternative: ‘SSL_F_SSL_READ’
See boost/asio/ssl/error.hpp.
Boost handles differences between OpenSSL versions.
cmake: fail if Boost is too old for OpenSSL v1.1
29497f7920