N3910: What can signal handlers do? -- Hans-J. Boehm

By Blog Staff | Feb 16, 2014 04:47 PM | Tags: None

Note: This paper was among the final papers adopted into draft C++14 yesterday at the Issaquah WA USA ISO C++ meeting.

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3910

Date: 2014-02-14

What can signal handlers do?

by Hans-J. Boehm

Excerpt:

This is a revision of N3787. It attempts to reflect the remaining comments from CWG discussions in Chicago. It also reflects further in person discussions with Jens Maurer and Clark Nelson at the Issaquah meeting, and subsequent feedback from both SG1 and core. Some of the wording here came directly from Jens.

... in the process of relaxing the restrictions on asynchronous signal handlers to allow use of atomics, we inadvertently made it impossible to use even local variables of non-volatile, non-atomic type.

N3905: Extending std::search to use Additional Searching Algorithms (Version 4) -- Marshall Clow

By Blog Staff | Feb 16, 2014 04:40 PM | Tags: None

Note: This paper was among the papers adopted into the draft Library Fundamentals TS yesterday at the Issaquah WA USA ISO C++ meeting.

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3905

Date: 2014-02-14

Extending std::search to use Additional Searching Algorithms (Version 4)

by Marshall Clow

Excerpt:

Note: This is an update of n3703, from the summer 2013 mailing. ...

std::search is a powerful tool for searching sequences, but there are lots of other search algorithms in the literature. For specialized tasks, some of them perform significantly better than std::search. In general, they do this by precomputing statistics about the pattern to be searched for, betting that this time can be made up during the search.

The basic principle is to break the search operation into two parts; the first part creates a "search object", which is specific to the pattern being searched for, and then the search object is passed, along with the data being searched, to std::search.

This is done by adding an additional overload to std::search, and some additional functions to create the search objects.

Two additional search algorithms are proposed for inclusion into the standard: "Boyer-Moore" and "Boyer-Moore-Horspool". Additionally, the interface for the search objects is documented so that library implementers and end users can create their own search objects and use them with std::search.

...

Thanks to LWG, which reviewed an earlier version of this document, Matt Austern, who suggested overloading std::search, and especially Daniel Krügler, who wrote most of the wording for the standard, and Stephan T. Lavavej, who reviewed it.

C++ Papers for Issaquah - Library, Graphics, Networking, Numerics and Undefined Behavior

By Meeting C++ | Feb 12, 2014 12:51 PM | Tags: undefined behavior standardization numerics networking library issaquah intermediate graphics experimental c++14 advanced

This is the last part in the series for Issaquah, and its the most diverse:

C++ Papers for Issaquah - Library, Graphics, Networking, Numerics & Undefined Behavior

by Jens Weller

From the Article:

The 4th and last part about the C++ Papers for Issaquah. I already covered the first batch of proposals from the Library subgroup in the previous part, now its all about papers from Library, Graphics, Networking, Numerics and Undefined Behavior. A very diverse part.

C++ Papers for Issaquah - Library I

By Meeting C++ | Feb 11, 2014 03:58 AM | Tags: standardization issaquah intermediate experimental c++14 advanced

The third part of my series about the papers for Issaquah is about the first batch of library proposals

C++ Papers for Issaquah - Library I

by Jens Weller

From the article:

The 3rd part of the C++ papers for Issaquah series will be about the library proposals. The last part covered the papers from concepts, database and evolution. There are a lot of proposals from the library group, and I think some of them are the most interesting, as they don't have any impact on the core language.

C++ Papers for Issaquah - Concepts, Database and Evolution

By Meeting C++ | Feb 6, 2014 04:33 PM | Tags: standardization issaquah intermediate experimental evolution database concepts advanced

This is the second part of my series about the papers for the next C++ committee meeting in Issaquah:

C++ Papers for Issaquah - Concepts, Database & Evolution

by Jens Weller

From the article:

This is the second part about the papers for the C++ committee meeting in February in Issaquah. This time featuring papers from the subgroups of concept, database and evolution. Again, most papers in this series aim for a standard after C++14, most important for C++14 will be the national comments on the new standard. Also there are no new papers from the core working group, only the active issues, defects report and closed issues report are on this mailing.

N3906: ISO/IEC PDTS 18822, File System, National Body Comments -- Barry Hedquist

By Blog Staff | Feb 4, 2014 09:49 AM | Tags: None

Note: These are the results of the main international review and comment ballot for the File System TS. The Issaquah ISO C++ meeting that begins on Monday will be a ballot resolution meeting for both C++14 and the File System TS.

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3906

Date: 2014-02-03

ISO/IEC PDTS 18822, File System, National Body Comments

by Barry Hedquist

Excerpt:

Attached is a revision of SC22 N4901, the complete set of National Body Comments submitted to JTC1 SC22 in response to the SC22 Letter Ballot for ISO/IEC PDTS 18822, File System.

N3900: WG21 2014-01-31 Telecon Minutes -- Herb Sutter

By Blog Staff | Feb 3, 2014 12:33 PM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3900

Date: 2014-01-31

WG21 2014-01-31 Telecon Minutes

by Herb Sutter

Excerpt:

The focus of the upcoming face to face meeting in Issaquah will be ballot resolution:

• C++14 CD ballot comment resolution to produce a C++14 DIS at the end of Issaquah.
• File System PDTS ballot comment resolution.

In remaining time we will also work on issues lists and TS work.

N3852: C++ CD Comment Status, Rev. 3 -- William M. Miller

By Blog Staff | Jan 30, 2014 12:17 PM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3852

Date: 2014-01-30

C++ CD Comment Status, Rev. 3

by William M. Miller

Excerpt:

This document summarizes the status of WG21 prior to the 2014-02 (Issaquah) meeting in addressing National Body comments on Committee Draft document N3690.

In total, 85 comments were received. To date, 41 have been accepted as proposed, 8 have been accepted with modifications, 22 have been rejected, and 14 remain to be addressed.

C++ Papers for Issaquah -- Concurrency

By Meeting C++ | Jan 29, 2014 07:47 AM | Tags: standardization performance intermediate experimental concurrency c++14 advanced

So I just started to read through the papers for the next C++ committee meeting in Issaquah in February, first part is about Concurrency:

C++ Papers for Issaquah -- Concurrency

by Jens Weller

From the article:

In february the C++ committee is going to meet for a week in Issaquah, it could be the final Meeting for C++14, the papers in this series will reflect both, C++14 and the standard that will come after it. Currently mostly known as C++1y. A lot of papers that are not part of C++14 will be formed into technical specifications, which some will then become C++1y later. Like the last series, I will again focus on the working groups, and post the papers sorted by the name of the working group, starting with concurrency.

N3899: Nested Allocation -- Lawrence Crowl

By Blog Staff | Jan 24, 2014 06:55 PM | Tags: None

A new WG21 paper is available. A copy is linked below, and the paper will also appear in the next normal WG21 mailing. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N3899

Date: 2014-01-20

Nested Allocation

by Lawrence Crowl

Excerpt:

Stack allocation is generally faster than heap allocation. C and C++ have exploited this speed by allocating statically-sized local variables on the execution stack. With the exception of the rather limited alloca facility, all non-statically-sized objects could only be allocated on the heap.

That is, programmers had the choice between fast-but-limited and general-but-slow.

This paper explores some of the issues when refining allocation choices.