*Created by: sergeken* compiling server_http.hpp with g++ 7.1 gives the following error messages: ../../Prometheus/src/web_services/server_http.hpp:278:44: error: uninitialized variable ‘content_length’ in ‘constexpr’ function unsigned long long content_length; ^~~~~~~~~~~~~~ Changing the try-catch block as following fixes the issue. if(it!=request->header.end()) { try { unsigned long long content_length = stoull(it->second); if(content_length>num_additional_bytes) { //Set timeout on the following boost::asio::async-read or write function auto timer=this->get_timeout_timer(socket, config.timeout_content); boost::asio::async_read(*socket, request->streambuf, boost::asio::transfer_exactly(content_length-num_additional_bytes), [this, socket, request, timer] (const boost::system::error_code& ec, size_t /*bytes_transferred*/) { if(timer) timer->cancel(); if(!ec) this->find_resource(socket, request); else if(on_error) on_error(request, ec); }); } else this->find_resource(socket, request); } catch(const std::exception &e) { if(on_error) on_error(request, boost::system::error_code(boost::system::errc::protocol_error, boost::system::generic_category())); return; } }