EVP_KEYEXCH_free
EVP_KEYEXCH_free(kex); /* up-ref successful but push to stack failed */
sk_EVP_KEYEXCH_pop_free(kex_stack, EVP_KEYEXCH_free);
EVP_KEYEXCH_free(exchange);
EVP_KEYEXCH_free(data);
EVP_KEYEXCH_free(exchange);
EVP_KEYEXCH_free(exchange);
EVP_KEYEXCH_free(ctx->op.kex.exchange);
EVP_KEYEXCH_free(rctx->op.kex.exchange);
void EVP_KEYEXCH_free(EVP_KEYEXCH *exchange);
EVP_KEYEXCH_free(kex);
EVP_KEYEXCH_free(kex);