Report from the February 2019 ISO C++ meeting (Core Language working group)

by Jason Merrill

The February 2019 ISO C++ meeting was held in Kailua-Kona, Hawaii. As usual, Red Hat sent three developers to the meeting: I attended in the Core Language working group, Jonathan Wakely in Library, and Thomas Rodgers in SG1 (parallelism and concurrency). The meeting went smoothly, although there was significant uncertainty at the beginning where we would end up. In the end, Modules and Coroutines were accepted into the C++20 draft, so now we have our work cut out for us nailing down the remaining loose corners. Here ar highlights from the meeting...

Italian C++ Conference 2019

The C++ Conference, made in Italy
Saturday June 15, Milan

We are excited to announce the conference keynote speaker
Andrei Alexandrescu

CPPP

by Jonathan Boccara

Here is an exciting piece of news for the C++ community: the CPPP conference has been officially announced!

The Day I Fell in Love with Fuzzing

by Chris Wellons

In 2007 I wrote a pair of modding tools, binitools, for a space trading and combat simulation game named Freelancer. The game stores its non-art assets in the format of “binary INI” files, or “BINI” files. The motivation for the binary format over traditional INI files was probably performance: it’s faster to load and read these files than it is to parse arbitrary text in INI format...

Boost 1.70.0 released

New Libraries​

• Outcome: A set of tools for reporting and handling function failures in contexts where directly using C++ exception handling is unsuitable, from Niall Douglas.
• Histogram: Fast and extensible multi-dimensional histograms with convenient interface for C++14, from Hans Dembinski.

Updated Libraries​

1. Asio:

• Fixed a Windows-specific memory leak that may occur when system_executor is used.
• Improved dispatch, post and defer documentation.
• Fixed compile errors that occur when using the composed read and write operations with MSVC 11.0.
• Fixed a macOS-specific warning about the deprecation of OSMemoryBarrier.
• Changed composed asynchronous read and write operations to move buffer sequence objects.
• Added a fallback error code for when we OpenSSL produces an SSL_ERROR_SYSCALL result without an associated error.
• Suppressed the eof error on SSL shutdown as it actually indicates success.
• Ensured SSL handshake errors are propagated to the peer before the local operation completes.
• Fixed buffer_sequence_begin and buffer_sequence_end to prevent implicit conversion.
• Changed the range-based asynchronous connect operation to deduce the EndpointSequence iterator type.
• Fixed calculation of absolute timeout when the backend uses pthread_cond_timedwait.
• Changed receive operations to return the correct number of bytes transferred when truncation (error::message_size) occurs on a datagram-oriented socket.
• Enabled recycling of the memory used to type-erase a function object with the polymorphic executor.
• Added a new BOOST_ASIO_DISABLE_VISIBILITY configuration #define.
• Added the noexcept qualifier to various functions.
• Added a constructor for local::basic_endpoint that takes a string_view.
• Relaxed the completion condition type requirements to only require move-constructibility rather than copy-constructibility.
• Added a make_strand helper function.
• Added a new async_compose function that simplifies the implementation of user-defined asynchronous operations.
• Added a new DynamicBuffer_v2 concept which is CopyConstructible.
• Updated the Coroutines TS support and promoted it to the asio namespace.
• Added a new async_result form with an initiate static member function.
• Added the ability to use custom I/O executors with I/O objects (such as sockets).
• This release includes a number of new features, bug fixes, performance enhancements, and documentation improvements. Notable changes include:
• Consult the Revision History for further details.

...

CppCast Episode 194: Linear Algebra and Audio with Guy Davidson

by Rob Irving and Jason Turner

Guy Davidson is the Principal Coding Manager of Creative Assembly, makers of the Total War franchise, Alien: Isolation and Halo Wars 2, Guy has been writing games since the early 1980s. He is now also a contributor to SG14, the study group devoted to low latency, real time requirements, and performance/efficiency especially for Games, Financial/Banking, and Simulations, and to SG13, the HMI study group. He speaks at schools, colleges and universities about programming and likes to help good programmers become better programmers.

How to Emulate the Spaceship Operator Before C++20 with CRTP

by Henrik Sjöström

Making a class comparable is usually something of a chore. In C++20 we’ll get the “three-way comparison operator” or informally spaceship operator <=>. It will allow the compiler to create comparison operators when we want a simple lexicographical comparison and when we have a more complex comparison we only need to implement a single operator to be able to do all comparisons...

C++ Insights - Variadic Templates

by Rainer Grimm

Variadic templates are a C++ feature which looks quite magic the first time you see it. Thanks to C++ Insights, most of the magic disappears...

Overload 150 is now available

This means war!.
Careless use of language can upset people. Frances Buontempo asks what we can do to make the developer experience better.

NullableAttribute and C# 8.
C# 8 will bring many new features. Jon Skeet investigates the metadata representation of Nullable Reference Types.

lvalues, rvalues, glvalues, prvalues, xvalues, help!.
C++11 introduced new value categories. Anders Schau Knatten explains his way of thinking about them.

Modern SAT solvers: fast, neat and underused (part 1 of N).
SAT solvers can quickly find solutions to Boolean Logic problems. Martin Hořeňovský demonstrates how this can be used to solve arbitrary Sudoku puzzles.

The Duality….
Genetic algorithms can find solutions that other algorithms might miss. Anders Modén discusses their use in conjunction with back-propagation for finding better solutions.

Blockchain-Structured Programming.
Coins are a wedge-shaped piece used for some purpose. Teedy Deigh shares her angle on the technology underpinning crypto-currencies.

The BooSTL Algorithms: Boost Algorithms That Extend the STL (3/3)

by Jonathan Boccara

The BooSTL algorithms are what we can call the Boost algorithms which are in the same spirit as those of the STL. They encapsulate operations on collections, and being able to use them allows to write (or re-write) more expressive code. To cover all their contents, we split up the articles of the BooSTL into three parts:

• the BooSTL algorithms on sorting and partitioning,
• the BooSTL algorithms on searching,
• the other BooSTL algorithms.

So here we go to cover the rest of the BooSTL algorithms which are not in sorting, partitioning nor searching.