Events

CppCon 2015 Program Highlights, 3 of N

The CppCon 2015 conference program has been posted for the upcoming September conference. We’ve received requests that the program continue to be posted in “bite-sized” posts, a few sessions at a time, to make the 100+ sessions easier to absorb, so here is another set of talks. This series of posts will conclude once the entire conference program has been posted in this way.

 

The C++ possess another language inside it: the template language. It is useful for a lot of things, from writting less code to compile time computations or checks, but can lengthen compile time too. To master it is not easy.

The following interrelated CppCon 2015 talks tackle these issues and more (part 1).

In this post:

  • Expression Templates - What, Why, When, Where
  • Visualizing Template Instantiations - Templator Demo
  • Variadic Templates - Guidelines, Examples and Compile-time computation
  • Variable Templates - C++14 compile-time computation
  • How I stopped worrying and love metaprogramming

 

Expression Templates - What, Why, When, Where - Part I, Part II, Part III

Expression Templates is one of this C++ idiom people learn to either love or hate. The main issues with ET is that everubody has its own conception about what they are, when they should be used, what benefits they give and what are their trade off. For a long time, Expression Tempaltes has been seen has a way to improve temporary heavy code. If the seminal implementation of ET by Todd Veldhuizen was actually about this, the landscape has changed since C++11 and C++14.

This workshop will go over : - what are exactly Expression Templates and what kind of use case they can solve elegantly and efficiently - what are the benefits that one may reap by using expression tempalte in its library - what are the real cost of expressont empaltes both at runtime and compile-time - which tools to use to not reinvent the tempalte wheel everytime including an introduction to Boost.PROTO an Boost.HANA.

The main objective is to clarify why, even in C++1*, this idiom has a meaningful set of applciations and how to navigate around its pitfalls.


Visualizing Template Instantiations - Templator Demo

Many C++ beginners shy away from employing templates in their code, because of the myth of templates being hard. Even seasoned C++ developers can have problems manually interpreting template code correctly as Olve Maudal's C++ pub quiz demonstrates. Overloads and template specializations make it hard for programmers and also IDEs to show a developer what happens without compiling a program and even with a compile one might not get, what actually happens unless an unintelligible error message from your compiler appears.

My students tried to alleviate that problem by visualizing template instantiation and overload selection in a C++ IDE and allow to navigate through template code in instantiation context that a compiler would only create internally and that is otherwise not available for humans. While still in its nascent state I hope to show what is possible and if things go as planned at the time of the submission you should be able to solve the template pub quiz questions without running the programs.


Variadic Templates - Guidelines, Examples and Compile-time computation

Writing class templates and functions accepting a variable number of arguments has been a burden before C++11. With variadic templates, both class templates with a variable number of arguments as well as functions can be formulated much easier and more type safe way.

Nevertheless, the authoring of variadic templates can be challenging for the uninitiated. Even the interpretation of variadic template code can be a problem, as Olve Maudal's famous pub quiz shows.

This session will build up understanding and the ability to use and author variadic template functions and variadic template classes from easy examples up to more complicated applications such as employing std::forward correctly, std::integer_sequence and other upcoming language features such as a template UDL operator that bridges the gap between string literals and std::integer_sequence.

Understanding pack expansion, sizeof... and other hard to get on first sight issues are my goal. In the end you should have seen guidelines that help you avoid the template instantiation trap from the pub quiz and correct usage of std::forward in your variadic templates.


Variable Templates - C++14 compile-time computation

C++11 introduced Variadic Templates, constexpr Functions and Literal Types that ease and allow type-safe computations at compile time. For embedded development this is an important aspect, because it provides a means to create ROMable data in type-safe C++.

In combination with C++14 mechanism of Variable Templates, that actually defines constants, and the relaxed constexpr function rules there are unprecedented possibilities for compile-time computations.

This talk does not only show the mechanisms available but also demonstrates non-trivial examples, how they can be used to compute interesting data at compile time.


How I stopped worrying and love metaprogramming

Horrible software engineering technique conceived in the forge of Hell or the Only True Way of doing C++ in 2015, template metaprogramming and its cohort of companion techniques are sure to create animation in a group of programmers.

What if we were to tell you that an actual software product, actually sold to real customers and in production for now several years has been built on it? What if we were to tell you that a lot of advanced template techniques helped us to build a better software faster?

This talk is all about real life examples of template metaprogramming, why they are useful and when and how you could use them in your own projects.

CppCon 2015 Program Highlights, 2 of N

The CppCon 2015 conference program has been posted for the upcoming September conference. We’ve received requests that the program continue to be posted in “bite-sized” posts, a few sessions at a time, to make the 100+ sessions easier to absorb, so here is another set of talks. This series of posts will conclude once the entire conference program has been posted in this way.

 

The standard template library (STL) is an important part of the C++ language. Knowing what there is inside and how to use it is an important part to create a program.

The following interrelated CppCon 2015 talks tackle these issues and more.

In this post:

  • STL Algorithms in Action
  • Enhancing STL containers
  • C++11/14/17 Atomics the Deep dive: the gory details, before the story consumes you!
  • Parallelizing the C++ Standard Library
  • Ranges and the Future of the STL

 

STL Algorithms in Action

This will be an entertaining trip through the STL algorithms, where we will view many of them in their natural habitats, going about their natural algorithm business. Then we will take some of them out of their native environments and make them do tricks that are entirely unexpected. In the end, you will gain a new appreciation for what the algorithms are and how pervasively they can be used throughout your code.

 

Enhancing STL containers

STL has a big history. Due to class paradigm of C++, many STL containers have a flat layout in memory, i.e. containers naturally store objects and address objects rather than their indexing entities such as smart pointers (which are, strictly speaking, objects too). This model has a benefit of lower memory fragmentation, that causes better CPU cache performance. However, many tasks in real life require reordering of objects, that requires compexity of O(n*q), where q is a size of an object and n is a compexity measured in operations. Thus, some imlementations of operations with reordering objects in some containers are much slower that they could be. This problem could sometimes be solved by storing “pointers” as index entities in containers instead of the objects by themselves, what improves performance by q times, but causes memory fragmentation and worse cache performance. Algorithmically, the solution with pointers is obviously better, but it is still not the most efficient one. In the presentation I will show myimplementations of containers using both approaches and having the best of two worlds. I will compare these methods with classical and modern approaches and draw some conclusion, encouraging everybody to use the power of algorithms with C++.

 

C++11/14/17 Atomics the Deep dive: the gory details, before the story consumes you!

In 2011, C++11 atomics offered three memory models but 6 settings. Most compilers have started implementing most of these (relaxed, seq_cst, acquire, release, acq_rel) but not consume (For that you will need to see Paul's talk which naturally follows this talk.) For this, I will deep dive into what each memory model setting means (especially for Games Development and low latency, a new SG14 in the C++ Standard) and how C++11 atomics are used to improve handling of mutable shared state. We have improved on it in C++14 and have more crazy things planned for C++17. I will also look at how C++ atomics are a natural precursor to SG5's Transactional Memory which was approved in Lenexa for publication.

 

Parallelizing the C++ Standard Library

As the era of frequency scaling comes to an end, multi-core parallelism has become an essential focal point in computational research. Mainstream languages, however, have not yet adapted to take full advantage of parallelism provided by the hardware. While new languages such as Rust and Swift are catching on and implementing multi-core algorithms in their libraries, C++ has only started to do so. A parallel Standard Library could bring with it many positive features that users can begin taking advantage of.

This talk will focus around two standards proposals, N4409 and N4406. N4409 outlines the details of a parallel Standard Library and features of these new parallel algorithms. The complementary N4406 outlines abstractions to take advantage of various mechanisms for parallel execution. We will cover the reasons why the new Standard Library would be beneficial to C++ users and our experience implementing these algorithms in HPX. The presentation will address what exactly the two proposals define, the challenges we faced, and the results we collected. In addition, we will discuss extensions made to these proposals and the C++11/14 standard in HPX to support these semantics in a distributed environment.

 

Ranges and the Future of the STL

Range-based interfaces are functional and composable, and lead to code that is correct by construction. With concepts and ranges coming to the STL, big changes are in store for the Standard Library and for the style of idiomatic C++. The effort to redefine the Standard Library is picking up pace. Come hear about one potential future of the STL from one of the key people driving the change.

CppCon 2015 Keynote #2: Better Code -- Data Structures (Sean Parent)

cppcon-040.PNGThe CppCon 2015 program is already chock-full of strong topics and speakers, with a handful of the big talks still to be announced. Here's another of those...

From the announcement:

Keynote: Sean Parent

We are announcing the second keynote for next month’s conference.

Sean Parent, principal scientist at Adobe, will be continuing his “Better Code” keynote series from last year’s C++Now keynote (on complete types) with “Better Code: Data Structures.”

Abstract: The standard library containers are often both misused and underused. Instead of creating new containers, applications are often structured with incidental data structures composed of objects referencing other object. This talk looks at some of the ways the standard containers can be better utilized and how creating (or using non-standard library) containers can greatly simplify code. The goal is no incidental data structures.

Speakers bio: Sean Parent is a principal scientist and software architect for Adobe’s mobile digital imaging group. Sean has been at Adobe since 1993 when he joined as a senior engineer working on Photoshop and later managed Adobe’s Software Technology Lab. In 2009 Sean spent a year at Google working on Chrome OS before returning to Adobe. From 1988 through 1993 Sean worked at Apple, where he was part of the system software team that developed the technologies allowing Apple’s successful transition to PowerPC.

CppCon 2015 Program Highlights, 1 of N

The CppCon 2015 conference program has been posted for the upcoming September conference. We've received requests that the program continue to be posted in "bite-sized" posts, a few sessions at a time, to make the 100+ sessions easier to absorb, so here is another set of talks. This series of posts will conclude once the entire conference program has been posted in this way.

 

There is lots -- lots -- of existing C++ code. How can you effectively bring existing C++ code forward to C++11/14? How can you upgrade your coding styles and conventions? How can tools help you and your team to use correct modern C++ in your production projects?

The following interrelated CppCon 2015 talks tackle these issues and more.

In this post:

  • Keynote: Writing Good C++14 (Bjarne Stroustrup)
  • Plenary: Writing Good C++14 By Default (Herb Sutter)
  • A Few Good Types: Evolving array_view and string_view For Safe C++ Code (Neil MacIntosh)
  • More than Lint: Modern Static Analysis For C++ (Neil MacIntosh)

 

Keynote: Writing Good C++14

How do we use C++14 to make our code better, rather than just different? How do we do so on a grand scale, rather than just for exceptional programmers? We need guidelines to help us progress from older styles, such as “C with Classes”, C, “pure OO”, etc. We need articulated rules to save us from each having to discover them for ourselves. Ideally, they should be machine-checkable, yet adjustable to serve specific needs.

In this talk, I describe a style of guidelines that can be deployed to help most C++ programmers. There could not be a single complete set of rules for everybody, but we are developing a set of rules for most C++ use. This core can be augmented with rules for specific application domains such as embedded systems and systems with stringent security requirements. The rules are prescriptive rather than merely sets of prohibitions, and about much more than code layout. I describe what the rules currently cover (e.g., interfaces, functions, resource management, and pointers). I describe tools and a few simple classes that can be used to support the guidelines.

The core guidelines and a checker tool reference implementation will be open source projects freely available on all major platforms (initially, GCC, Clang, and Microsoft).

Use, comment, and contribute!

Speaker: Bjarne Stroustrup, Managing Director, Morgan Stanley. Stroustrup is the creator and original implementer of C++. He is also a Visiting Professor in Computer Science at Columbia University, a Distinguished Research Professor in Computer Science at Texas A&M University, and continues to actively participate and lead language evolution in the ISO C++ committee.

 

Writing Good C++14 By Default

Modern C++ is clean, safe, and fast. It continues to deliver better and simpler features than were previously available. How can we help most C++ programmers get the improved features by default, so that our code is better by upgrading to take full advantage of modern C++?

This talk continues from Bjarne Stroustrup’s Monday keynote to describe how the open C++ core guidelines project is the cornerstone of a broader effort to promote modern C++. Using the same cross-platform effort Stroustrup described, this talk shows how to enable programmers write production-quality C++ code that is, among other benefits, type-safe and memory-safe by default -- free of most classes of type errors, bounds errors, and leak/dangling errors -- and still exemplary, efficient, and fully modern C++.

Background reading: Bjarne Stroustrup’s 2005 “SELL” paper, “A rationale for semantically enhanced library languages," is important background for this talk.

Speaker: Herb Sutter, author and chair of the ISO C++ committee.

 

A Few Good Types: Evolving array_view and string_view for Safe C++ Code

The Library Fundamentals TS already contains a string_view type, and possibly soon an array_view type. These are important and should be used pervasively as function parameters, especially instead of (pointer, length) pairs which are generally unsafe. They offer additional benefits in the form of decoupling: allowing functions to be specified in terms of high-level views rather than references to specific, concrete string and container types which bind both caller and callee to a specific implementation detail. As a specific example, using string_view in function signatures allows them to be called with any of the endless proliferation of string types that exist in codebases today (std::string, CStringT, char*, BSTR, HSTRING, MyString etc).

We can and should evolve these types further as a key part of achieving memory safety for C++ code.

This example-driven talk shares our experience with preventing defects in large-scale commercial C++ codebases by applying modestly evolved versions of the proposed array_view and string_view types, plus a small number of related types such as not_null. Adopting these types enables simpler and safer code that eliminates important classes of defects by construction. The types are carefully designed to have usually exactly zero space and time overhead over the current unsafe idioms they replace, so as to leave no valid performance reason against adopting them. Using these types enables high-quality static analysis, and is allowing Microsoft to fully replace non-standard and non-portable annotation systems for type and memory safety in our own code bases.

We believe this approach is generally applicable to code at all levels, from application code down to the most performance-sensitive systems code. An open source reference implementation of the types that supports all major compilers and platforms will be available on GitHub.

More than Lint: Modern Static Analysis for C++

Static analysis tools have the potential to significantly improve programmer productivity as well as the safety, reliability and efficiency of the code they write. Modern static analysis has moved well beyond the mental model people often have based on “lint”: just finding simple “typos” or “thinkos”. Static analysis can find subtle, complex bugs early, identify opportunities to improve performance, encourage consistent style and appropriate usage of libraries and APIs.

This talk will look at the different purposes static analysis tools can be used to meet all these different goals. It will present specific examples from our experience working with sophisticated analysis tools on large, commercial codebases. The talk will also present a specific implementation of a modern static analysis toolkit for C++. This toolkit is being used in a number of different contexts: to provide tool-based enforcement of new coding guidelines and rules, to migrate people to modern C++ coding idioms and to find important security and reliability defects. One notable example of its use is to implement the checker for enforcement of a core set of coding guidelines that are presented in Bjarne Stroustrup’s keynote address.

Some of the tools described in the talk will be available for download as a Community Technology Preview in the latter part of 2015.

Speaker: Neil MacIntosh, Microsoft. Neil is the lead for the C++ static analysis frameworks used widely within Microsoft, including PREfix, PREfast, and ESPx, and is currently involved on making them work better with portable C++14 code rather than nonstandard annotations.

CppCon 2015 program additions posted

cppcon-046.PNGFrom the cppcon.org announcement:

2015 Program Additions

Most of this fall’s program is already online, but we are still working on it. Today we are announcing three new sessions and a panel.

Herb Sutter will be presenting “Writing Good C++14 By Default.” Herb’s session will build on Bjarne Stroustrup’s keynote of the previous day on “Writing Good C++14.”

Chandler Carruth, C++ Language and Compiler Lead at Google, will be presenting “Tuning C++: Benchmarks, and Compilers, and CPUs! Oh My!

Sumant Tambe will be presenting “Reactive Stream Processing in Industrial IoT using DDS and Rx.cpp,” which includes a live demo of a distributed complex event processing system for Internet of Things.

Our Monday evening panel will be Grill the Committee, featuring the opportunity for audience members to question members of the ISO C++ committee. We’ve not yet identified the panel members, but last year’s panel featured a dozen committee members and we’ll have a similar panel this year.

19 C++ User Group Meetings in August

The monthly overview on upcomging C++ User Group meetings:

19 C++ User Group Meetings in August

by Jens Weller

A short overview:

5.8 C++ UG Saint Louis - "Fun with Lambdas" Lightning Talk\, Interview Questions and more
5.8 C++ UG Austin - Introduction to the QT Framework using C++ and QML
6.8 C++ UG Edinburgh - C++ Edinburgh
10.8 C++ UG Denver - Denver Tech Center C++ Developers
12.8 C++ UG Utah - Regular Monthly Meeting
12.8 C++ UG San Francisco/ Bay area - Presentation and Q&A
12.8 C++ UG Washington, DC - Q & A / Info Sharing
17.8 C++ UG Austin - North Austin Monthly C/C++ Pub Social
17.8 C++ UG Juce - Deploy Pure Data patches to any OS with JUCE
18.8 C++ UG Berlin - TBA
19.8 C++ UG Düsseldorf - Treffen der C++ User Gruppe NRW
19.8 C++ UG Hamburg - constexpr
20.8 C++ UG Ruhrgebiet - August Meetup - std::advance(CodingStandard, Modern::c++)
24.8 C++ UG Göteborg - Let's meetup and discuss the format for this group
25.8 C++ UG Chicago - Using NuGet to manage external dependencies in Visual C++ builds
26.8 C++ UG San Francisco/ Bay area - Workshop and Discussion Group
26.8 C++ UG Washington, DC - Q & A / Info Sharing
26.8 C++ UG Aarhus - Access Guards
27.8 C++ UG Munich - Pruning Error Messages From Your C++ Template Code

C++ Siberia 2015

Program, speakers etc. are all online now in Russian.

C++ Siberia 2015

Organized by Sergey Platonov

What to expect at Siberia C++:

The event will take place in Novosibirsk, Siberia, Russia in August 2015. People from Yandex, Boost, PVS-Studio and many more companies will share their knowledge on compilers, concurrency and much more.

CppCon 2015 program is available: 100+ talks, all new

cppcon-054.PNGThe CppCon 2015 program has been posted! A few additional well-known speakers will also be announced soon for the remaining plenary sessions, but the majority of the program is now set: After the opening keynote by Bjarne Stroustrup on "Writing Good C++14," once again there are 100+ top-quality talks in 6 tracks all week long at this year's premier C++ festival, presented by over 80 speakers from around the world.

Note that there are no repeats -- all of the 100+ talks are new since last year. (If you missed last year's talks, you can watch them for free online on YouTube and Channel 9.) This year the program committee had even more submissions than last time, nearly twice as many as could be accepted. Even though this meant turning down lots of very good talk proposals simply for lack of room, the good news is that's because there was so much even stronger material, and this year's program is packed with the very best topics and content on C++ available this year. Register now for September 20-25, 2015!

Here's the announcement:

CppCon 2015 Program Available

The CppCon 2015 Program is now (mostly) available with talk titles, abstracts, and speakers. The program contains over 100 one-hour sessions by over 80 speakers including many speakers returning from last year’s very successful program as well as many new voices. Not all sessions are announced yet, but we have announced our opening keynote by C++ creator Bjarne Stroustrup on Writing Good C++14.

Finally, we would like to thank the program committee, the speakers on the program, and the many more who proposed talks which we unfortunately just couldn’t squeeze in this year. Thank you for your hard work and enthusiastic support for this year’s program!