The Absurdity of Error Handling: Finding a Purpose for Errors in Safety-Critical SYCL Erik Tomusk CppCon 2023 October 5, 2023© 2023 Codeplay Software Ltd. Codeplay Corporate Slide 2© 2023 Codeplay explicitly stated© 2023 Codeplay Software Ltd. Outline • Definition of Safety • Definition of Error Handling • Case Study • Why is this Important? • Is it Really so bad? • What does this mean for execution time (in mainstream compilers) 17Definition of Error Handling 18© 2023 Codeplay Software Ltd. Definition of Error Handling • Exceptions and error codes are sometimes used for reporting or information

CppCon 2024 Customizing Compilation Error Messages Formatting a Compile-Time String During Substitution Failure Patrick Roberts, P.E. Principal Software Engineer 1CppCon 2024 What problem does solve? 2CppCon 2024 3CppCon 2024 4CppCon 2024 5CppCon 2024 6 Guidelines for a helpful error message Where is the error? ✅ What is wrong? ✅ How can it be fixed? ❌CppCon 2024 7CppCon 2024 8CppCon 2024 9

Modern C++ Handling Phil Nash Error2018 2019series disappointments of a (total) Part 1int parse_int(std::string_view number)// TODO: +, -, digit separators? int acc = 0; for(char c first_digit = false; } return ParseStatus::Numeric; } 42 42 (starts with an int) Error: x42 is not an int test("42"); test("42x"); test("x42"); [[nodiscard]] void test(std::string_view int)”, i); break; case ParseStatus::NonNumeric: std::println(“Error: {} is not an int", str); break; } }int parse_int(std::string_view number) {

TechAtBloomberg.com © 2024 Bloomberg Finance L.P. All rights reserved. • Create a basic HTTP server. • Allow a single-threaded server handling multiple clients. • Use the sender/receiver asynchronous work consist of accepting incoming client connections. • Each client processes requests until an error is received. Basic DesignTechAtBloomberg.com © 2024 Bloomberg Finance L.P. All rights reserved. std::execution (sender/receiver): http://wg21.link/p2300 • https://github.com/NVIDIA/stdexec.git • https://github.com/beman-project/execution26 • Sender/receiver networking: http://wg21.link/p2762 • Implementation:

Design patterns for error handling in C++ programs using parallel algorithms and executors Mark Hoemmen* mhoemmen@stellarscience.com CppCon 2020 * hoʊ’mən, or hœm’mən; he/himWho am I? • > 10 years 2017 • Started new job at Stellar Science in March Eschew raw pointersOutline • Parallelism makes error handling harder… • …C++ parallel algorithms and tasks specifically • Message Passing Interface (MPI): Responsiveness ILLIAC IV: the 1st massively parallel computer (image: Steve Jurvetson)Parallel hinders error handling • … because parallelism relaxes execution order – Deliberately, to improve performance

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 6.3 HTTP servers and clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . implementions of HTTP (HTTPServer and AsyncHTTPClient). • An asynchronous networking library including the classes IOLoop and IOStream, which serve as the building blocks for the HTTP components and can other protocols. The Tornado web framework and HTTP server together offer a full-stack alternative to WSGI. While it is possible to use the Tornado HTTP server as a container for other WSGI frameworks

Prerequisites: Tornado 6.3 requires Python 3.9 or newer. The following optional packages may be useful:pycurl [http://pycurl.io/] is used by the optional tornado.curl_httpclient. Libcurl version 7.22 or higher is required browser HTTP servers and clients tornado.httpserver — Non-blocking HTTP server tornado.httpclient — Asynchronous HTTP client tornado.httputil — Manipulate HTTP headers and URLs tornado.http1connection http1connection – HTTP/1.x client/server implementation Asynchronous networking tornado.ioloop — Main event loop tornado.iostream — Convenient wrappers for non-blocking socketstornado.netutil — Miscellaneous network

Oracle VM VirtualBox R ⃝ User Manual Version 4.2.32 c⃝ 2004-2015 Oracle Corporation http://www.virtualbox.org Contents 1 First steps 11 1.1 Why is virtualization useful? . . . . . . . . . . . . . . host floppy not found . . . . . . . . . . . . . . . . . . . . . . . . 212 12.7.5 Strange guest IDE error messages when writing to CD/DVD . . . . . . . 212 12.7.6 VBoxSVC IPC issues . . . . . . . . . . . VirtualBox base package. Currently, Oracle provides the one extension pack, which can be found at http://www.virtualbox.org and provides the following added functional- ity: a) The virtual USB 2.0 (EHCI)

requests to Node 2 ○ Node 2 acts as a service server, receives requests from Node 1, and sends back responses ■ Node 2 also uses parameters at run-time to change its behaviorWhat is ROS 2? ● In this ROS requests to Node 2 ○ Node 2 acts as a service server, receives requests from Node 1, and sends back responses ■ Node 2 also uses parameters at run-time to change its behavior ● Each node should be responsible requests to Node 2 ○ Node 2 acts as a service server, receives requests from Node 1, and sends back responses ■ Node 2 also uses parameters at run-time to change its behavior ● Each node should be responsible

Introductory Tutorial. Requirements Python [http://www.python.org] 2.5 (or a higher release of 2.x). Django [http://www.djangoproject.com] 1.4.5, 1.5 or higher South [http://south.aeracode.org/] 0.7.2 or higher compatibility issues) django-sekizai [https://github.com/ojii/django-sekizai] 0.7 or higher html5lib [http://code.google.com/p/html5lib/] 0.90 or higher django-i18nurls [https://github.com/brocaar/django-i18nurls] your database size to increase. Installing in a virtualenv using pip Installing inside a virtualenv [http://www.virtualenv.org] is the preferred way to install any Django installation. This should work on