Another year and another C++ Status! It’s hard to believe, but it’s my fifth time I am writing this summary. And, as usually, C++ language is very alive. The biggest news for the year?
Of course, it must be: the final draft for C++17!.
What else have happened? See my full report below.
Other reports: 2016, 2015, 2014, 2013, 2012.
Timeline
- January 14, Alex Stephanov is retiring.
- February 29 - March 5: ISO meeting in Jacksonville, FL, USA
- March 9, Clang 3.8 released
- April 19-23, - ACCU Conference
- April 1, Intel Compiler v17.0
- April 27, GCC 6.1 Released
- June 6-10, NDC Oslo
- June 20-25, ISO meeting in Oulu, Finland
- June 27, VS Update 3
- August 22, GCC 6.2 released
- Sep 2, Clang 3.9 released
- September 17 - 23, CppCon 2016
- November 7 - 12: ISO meeting Issaquah, WA, USA
- November 16, VS 2017 RC available!
- November 15 & 16, code::dive conference in Wroclaw, PL
- November 18 & 19 MeetingCpp, Berlin
C++11/14 compiler status
Before we dive into newest stuff, let’s recall what’s the status of C++11 and C++14 implementation.
Just for the reference Clang (since 3.4 ), GCC (since 5.0) and Intel (version 15.0) already have full support for C++11/14.
Visual Studio (as of current VS 15.0 RC) lacks some features: Expression SFINAE (Partial), Two-phase name lookup, C99 preprocessor (Partial). See this VS blog post for more information. Still, I don’t see that situation as a blocker.
C++17
Let’s now focus on the main topic from this year.
During the ISO meeting in Oulu (June), the Committee accepted the draft for C++17. This is definitely not a minor release since a lot of features were added!
Here’s what we’ll get in the version:
Language features
| Feature | Paper |
|---|---|
| New auto rules for direct-list-initialization | N3922 |
| static_assert with no message | N3928 |
| typename in a template template parameter | N4051 |
| Removing trigraphs | N4086 |
| Nested namespace definition | N4230 |
| Attributes for namespaces and enumerators | N4266 |
| u8 character literals | N4267 |
| Allow constant evaluation for all non-type template arguments | N4268 |
| Remove Deprecated Use of the register Keyword | P0001R1 |
| Remove Deprecated operator++(bool) | P0002R1 |
| Removing Deprecated Exception Specifications from C++17 | P0003R5 |
| Make exception specifications part of the type system | P0012R1 |
| Aggregate initialization of classes with base classes | P0017R1 |
| Lambda capture of *this | P0018R3 |
| Using attribute namespaces without repetition | P0028R4 |
| Dynamic memory allocation for over-aligned data | P0035R4 |
| Unary fold expressions and empty parameter packs | P0036R0 |
| Template argument deduction for class templates | P0091R3 |
| Non-type template parameters with auto type | P0127R2 |
| Guaranteed copy elision | P0135R1 |
| New specification for inheriting constructors (DR1941 et al) | P0136R1 |
| Direct-list-initialization of enumerations | P0138R2 |
| Stricter expression evaluation order | P0145R3 |
| constexpr lambda expressions | P0170R1 |
| Differing begin and end types in range-based for | P0184R0 |
| Pack expansions in using-declarations | P0195R2 |
| Structured Bindings | P0217R3 |
| Hexadecimal floating-point literals | P0245R1 |
| Ignore unknown attributes | P0283R2 |
| init-statements for if and switch | P0305R1 |
| Inline variables | P0386R2 |
| DR: Matching of template template-arguments excludes compatible templates | P0522R0 |
| Improving std::pair and std::tuple | N4387 |
constexpr if-statements | P0292R2 |
Library features
- Merged: The Parallelism TS, a.k.a. “Parallel STL.”, P0024R2
- Merged: The Library Fundamentals 1 TS (most parts), P0220R1
- Merged: File System TS, P0218R1
- Merged: The Mathematical Special Functions IS, PDF - WG21 P0226R1
Resources:
While the above features look quite ok, we could see during the year that people were not entirely satisfied with the standard. As you might recall, last year I posted a survey on the preferred features for C++17 (number of votes for a feature, multiple selections were accepted), over 650 participants:
And this is what went into the standard:
Note:array_view, string_view were renamed into span and string_span see this info, and here.
Not much to be honest… Fortunately, most of the really desired features are close to being standardized, so it’s good sign for C++20.
Also, you can see those slides from Michael Wang:
PDF: Michael Wong – C++17, is it great or just OK…
Still, other people aren’t such harsh for C++, Phil Nash: C++17 - Why it’s better than you might think.
I think that C++17 is a decent release. We could always have more, but the committee did a good job this year anyway.
If you’re unhappy about not having concept, ranges, modules in the standard… you can still play with their experimental versions!
What’s your opinion?
ISO C++ meetings
There were three committee meetings this year.
February 29 - March 5: Jacksonville, FL, USA
- Herb Sutter: Trip report: Winter ISO C++ standards meeting
- Botond Ballo, Trip Report: C++ Standards Meeting in Jacksonville, February 2016
- Trip Report C++ Meeting at Jacksonville—J. Daniel Garcia
- GoingNative 48: ISOC++ @Jacksonville Debriefing
June 20-25, Oulu, Finland
The most important meeting this year, they voted the C++17 draft!
- Herb Sutter: Trip report: Summer ISO C++ standards meeting (Oulu)
- M. Wong: C++17, All Final Features from Oulu in a Few Slides
November 7-12: Issaquah, WA, USA
- Botond Ballo: Trip Report: C++ Standards Meeting in Issaquah, November 2016
- Michael Wong: The view from Nov 2016 C++ Standard Meeting Issaquah
- GoingNative 55: ISO C++ @Issaquah Debriefing
Compiler Notes
Current versions, updates
The best resource to stay up to date with all the features and compiler releases is probably: cppreference.com/C++ compiler support.
Visual Studio
Current version VS 2015 update 3 (27th June 2016)
But you can check out the recent RC candidate for VS 2017: Visual Studio 2017 Release Candidate.
- C++14/17 Features and STL Fixes in VS “15” Preview 5
- VS 2015 Update 2’s STL is C++17-so-far Feature Complete, January 22, 2016
- Vcpkg: a tool to acquire and build C++ open source libraries on Windows
- Standards version switches in the compiler
- C++ Core Guidelines Checkers: Preview of the Lifetime Safety checker
There are also various libraries available from Microsoft:
GCC
- Gcc 6.1 released in 27th April (currently 6.3, December 21, 2016)
- GCC 6 Release Series Changes
- Among The Changes/Features Coming For GCC 6
- C++14 (the GNU++14 dialect) will be the default C++ mode over C++98
- C++ Concepts are now supported when running in the GNU++1z/C++1z mode.
- The libstdc++ library has experimental C++17 support for a number of new features along with an experimental implementation of the File System TS and the 2nd Library Fundamentals TS.
- GCC 6 Will Warn You About Misleading Code Indentations
- Current C++1y/C++14 Support in GCC
- Looking forward to GCC6 – Many new warnings
- The C++ Hightlights and more of GCC 6.1, meetingcpp
- library status
On Windows you can use the latest MinGW distro from nuwen.net (Stephan T. Lavavej): Nuwen MinGW distro updated with GCC 6.3 and Boost 1.63.
Clang
- Current version: 3.9.1 - 23 Dec 2016, Release Notes
- Current C++ Support in Clang
- libc++ C++1z Status
- 9 March 2016 - Clang 3.8 released
Clang has its implementation of modules; you can play with it here.
Intel compiler
- Version 17.0 appeared in April 1, 2016, 17.0 (XE 2017) (release notes)
- C++14 Features Supported by Intel® C++ Compiler
- C++17 Features Supported by Intel® C++ Compiler - a bit outdated?
Conferences
As usually, we had two main C++ conferences - CppCon and Meeting C++, but I’d like to mention another one where C++ was the core topic - code::dive from Wroclaw, PL. Plus, there’s NDC Oslo with a good set of talks as well.
CppCon
- Link to the official page
- Link to YouTube channel with videos from the conference this year
- Best CppCon 2016 talks, reddit
Trip reports:
Meeting C++
This year Bjarne Stroustrup gave the opening keynote (“What C++ is and what it will become”). The closing keynote was presented by Louis Dionne (“C++ metaprogramming: evolution and future directions”).
Code::Dive in Wroclaw, PL
November 15th & 16th, code::dive
At last a really awesome C++ conference in Poland! :)
This year the conference took two days, and it included a lot of talks about C++ and native development.
code::dive is non-profit, annual conference for C++ enthusiasts
sponsored by NOKIA. The main idea behind the conference is to share the
knowledge beyond cutting edge technologies and build networking
between the people.
Some of the presenters: Scott Meyers, Venkat Subramaniam, Andrei Alexandrescu, Dan Sacks, Ulrich Drepper, Michael Wong, Chandler Carruth, Sean Parent, and much more!
NDC Oslo 2016
NDC Oslo 2016, 6th-10th June 2016
Speakers: Andrei Alexandrescu, Anthony Williams, Dan Saks, Detlef Vollmann, Mark Isaacson, and more.
BTW: The main problem with the conferences: how to watch all of those valuable talks! :) One tip is to watch it at bigger speed (1.5x, 2.0x, …) in the player, but still, it requires a lot of time!
Books
Some of the books released this year worth seeing:
- Procedural Content Generation for C++ Game Development Paperback, January 30, 2016, January 30, 2016
- Optimized C++, by Kurt Guntheroth, May 21, 2016
- C++ Game Development Cookbook, by Druhin Mukherjee, May 30, 2016
- C++ Standard Library Quick Reference by Peter Van Weert Marc Gregoire, June 14, 2016
- Qt5 C++ GUI Programming Cookbook, by Lee Zhi Eng, July 29, 2016
- C++ in 24 Hours, 6th Edition, by Rogers Cadenhead, Jesse Liberty, August 13, 2016
- C ++ Windows Programming Paperback by Stefan Bjornander, September 12, 2016
- Options and Derivatives Programming in C++, by Carlos Oliveira, September 30, 2016
- C++: The Ultimate Beginners Guide to C++ Programing by Steve Tale, December 3, 2016
I am still waiting for Large-Scale C++ Volume I, John Lakos, but its release date is moving later and later…
Summary
I think that C++ developers were looking for much more with C++17. In 2015 we got a lot of promises, ideas about the new standard, so people started to dream too much. The reality appeared a bit different, a lot of those impressive features were not accepted or put on hold.
Still, we shouldn’t complain. C++ 17 will be a really decent release, and a lot of teams and companies are not even near accepting/using C++11. The adaptation is also an important factor when looking at the language use. It’s much better to have reliable, verified, checked features than something fragile that might change. I’d like to have concepts, ranges, modules soon… but C++20 is not that far. And yet I can play with those features using their quite stable experimental versions.
I’m glad to see that the committee is working consistently, and also quite transparently. You can feel the enormous community behind the language. So, all in all I think 2017 will be a good year for C++.
- What do you think about C++ in 2016?
- What was the most important event/news for you?
- Did I miss something? Let me know in comments!
The poll below: what's your favourite C++17 feature?