Trying to use devel/tcltls (version 1.6.7) with libressl, which no longer
supports SSLv2:

/etc/make.conf:
  WITH_OPENSSL_PORT= yes
  OPENSSL_PORT= security/libressl

Port compilation issues a couple of telltale warnings, but manages
to build the Tcl tls package nevertheless:

  tls.c:561:21: warning: implicit declaration of function 'SSLv2_method'
  is invalid in C99 [-Wimplicit-function-declaration]
                ctx = SSL_CTX_new(SSLv2_method()); break;
                                  ^
  tls.c:561:21: warning: incompatible integer to pointer conversion passing
  'int' to parameter of type 'const SSL_METHOD *' (aka 'const struct
   ssl_method_st *') [-Wint-conversion]
                ctx = SSL_CTX_new(SSLv2_method()); break;
                                  ^~~~~~~~~~~~~~
  /usr/local/include/openssl/ssl.h:1523:40: note: passing argument
  to parameter 'meth' here SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth);
                                       ^
  tls.c:1118:9: warning: incompatible integer to pointer conversion assigning
  to 'const SSL_METHOD *' (aka 'const struct ssl_method_st *') from 'int'
  [-Wint-conversion]
        method = SSLv2_method ();
               ^ ~~~~~~~~~~~~~~~
  3 warnings generated.


The resulting Tcl package is unfortunately unusable:

  $ tclsh8.6
  % package require tls
  couldn't load file "/usr/local/lib/tls1.6.7/libtls.so.1":
    /usr/local/lib/tls1.6.7/libtls.so.1: Undefined symbol "SSLv2_method"


Would be nice to autodetect availability of SSLv2 and SSLv3, or better yet,
disable both.