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Friday, April 3, 2026

Thursday, April 2, 2026

Hubs, intervals and mathDuring Q1 2026, I’ve been working in the following areas: boost::container::hub boost::container::hub is a nearly drop-in replacement of C++26 std::hive sporting a simpler data structure and providing competitive performance with respect to the de facto reference implementation plf::hive. When I first read about std::hive, I couldn’t help thinking how complex the internal design of the container is, and wondered if something leaner could in fact be more effective. boost::container::hub critically relies on two realizations: Identification of empty slots by way of std::countr_zero operations on a bitmask is extremely fast. Modern allocators are very fast, too: boost::container::hub does many more allocations than plf::hive, but this doesn’t degrade its performance significantly (although it affects cache locality). boost::container::hub is formally proposed for inclusion in Boost.Container and will be officially reviewed April 16-26. Ion Gaztañaga serves as the review manager. using std::cpp 2026 I gave my talk “The Mathematical Mind of a C++ Programmer” at the using std::cpp 2026 conference taking place in Madrid during March 16-19. I had a lot of fun preparing the presentation and delivering the actual talk, and some interesting discussions were had around it. This is a subject I’ve been wanting to talk about for decades, so I’m somewhat relieved I finally got it over with this year. Always happy to discuss C++ and math, so if you have feedback or want to continue the conversation, please reach out to me. Boost.Unordered Written maintenance fixes PR#328, PR#335, PR#336, PR#337, PR#339, PR#344, PR#345. Some of these fixes are related to Node.js vulnerabilities in the Antora setup used for doc building: as the number of Boost libraries using Antora is bound to grow, maybe we should think of an automated way to get these vulnerabilities automatically fixed for the whole project. Reviewed and merged PR#317, PR#332, PR#334, PR#341, PR#342. Many thanks to Sam Darwin, Braden Ganetsky and Andrey Semashev for their contributions. Boost.Bimap Merged PR#31 (std::initializer_list constructor) and provided testing and documentation for this new feature (PR#54). The original PR was silently sitting on the queue for more than four years and it was only when it was brought to my attention in a Reddit conversation that I got to take a look at it. Boost.Bimap needs an active mantainer, I guess I could become this person. Boost.ICL Recent changes in libc++ v22 code for associative container lookup have resulted in the breakage of Boost.ICL. My understanding is that the changes in libc++ are not standards conformant, and there’s an ongoing discussion on that; in the meantime, I wrote and proposed a PR to Boost.ICL that fixes the problem (pending acceptance). Support to the community I’ve been helping a bit with Mark Cooper’s very successful Boost Blueprint series on X. Supporting the community as a member of the Fiscal Sponsorship Committee (FSC).📝The C++ Alliance

Wednesday, April 1, 2026

Tuesday, March 31, 2026

Systems, CI Updates Q1 2026Code Coverage Reports - designing new GCOVR templates A major effort this quarter and continuing on since it was mentioned in the last newsletter is the development of codecov-like coverage reports that run in GitHub Actions and are hosted on GitHub Pages. Instructions: Code Coverage with Github Actions and Github Pages. The process has really highlighted a phenomenon in open-source software where by publishing something to the whole community, end-users respond back with their own suggestions and fixes, and everything improves iteratively. It would not have happened otherwise. The upstream GCOVR project has taken an interest in the templates and we are working on merging them into the main repository for all gcovr users. Boost contributors and gcovr maintainers have suggested numerous modifications for the templates. Great work by Julio Estrada on the template development. Better full page scrolling of C++ source code files Include ‘functions’ listings on every page Optionally disable branch coverage Purposely restrict coverage directories to src/ and include/ Another scrolling bug fixed Both blue and green colored themes Codacy linting New forward and back buttons. Allows navigation to each “miss” and subsequent pages Server Hosting This quarter we decommissioned the Rackspace servers which had been in service 10-15 years. Rene provided a nice announcement: Farewell to Wowbagger - End of an Era for boost.org There was more to do then just delete servers, I built a new results.boost.org FTP server replacing the preexisting FTP server used by regression.boost.org. Configured and tested it. Inventoried the old machines, including a monitoring server. Built a replacement wowbagger called wowbagger2 to host a copy of the website - original.boost.org. The monthly cost of a small GCP Compute instance seems to be around 5% of the Rackspace legacy cloud server. Components: Ubuntu 24.04. Apache. PHP 5 PPA. “original.boost.org” continues to host a copy of the earlier boost.org website for comparison and development purposes which is interesting to check. Launched server instances for corosio.org and paperflow. Fil-C Working with Tom Kent to add Fil-C https://github.com/pizlonator/fil-c test into the regression matrix https://regression.boost.org/ . Built a Fil-C container image based on Drone images. Debugging the build process. After a few roadblocks, the latest news is that Fil-C seems to be successfully building. This is not quite finished but should be online soon. Boost release process boostorg/release-tools The boostorg/boost CircleCI jobs often threaten to cross the 1-hour time limit. Increased parallel processes from 4 to 8. Increased instance size from medium to large. And yet another adjustment: there are 4 compression algorithms used by the releases (gz, bz2, 7z, zip) and it is possible to find drop-in replacement programs that go much faster than the standard ones by utilizing parallelization. lbzip2 pigz. The substitute binaries were applied to publish-releases.py recently. Now the same idea in ci_boost_release.py. All of this reduced the CircleCI job time by many minutes. Certain boost library pull requests were finally merged after a long delay allowing an upgrade of the Sphinx pip package. Tested a superproject container image for the CircleCI jobs with updated pip packages. Boost is currently in a code freeze so this will not go live until after 1.91.0. Sphinx docs continue to deal with upgrade incompatibilities. I prepared another set of pull requests to send to boost libraries using Sphinx. Doc Previews and Doc Builds Antora docs usually show an “Edit this Page” link. Recently a couple of Alliance developers happened to comment the link didn’t quite work in some of the doc previews, and so that opened a topic to research solutions and make the Antora edit-this-page feature more robust if possible. The issue is that Boost libraries are git submodules. When working as expected submodules are checked out as “HEAD detached at a74967f0” rather than “develop”. If Antora’s edit-this-page code sees “HEAD detached at a74967f0” it will default to the path HEAD. That’s wrong on the GitHub side. A solution we found (credit to Ruben Perez) is to set the antora config to edit_url: ‘{web_url}/edit/develop/{path}’. Don’t leave a {ref} type of variable in the path. Rolling out the antora-downloads-extension to numerous boost and alliance repositories. It will retry the ui-bundle download. Refactored the release-tools build_docs scripts so that the gems and pip packages are organized into a format that matches Gemfile and requirement.txt files, instead of what the script was doing before “gem install package”. By using a Gemfile, the script becomes compatible with other build systems so content can be copy-pasted easily. CircleCI superproject builds use docbook-xml.zip, where the download url broke. Switched the link address. Also hosting a copy of the file at https://dl.cpp.al/misc/docbook-xml.zip Boost website boostorg/website-v2 Collaborated in the process of on-boarding the consulting company Metalab who are working on V3, the next iteration of the boost.org website. Disable Fastly caching to assist metalab developers. Gitflow workflow planning meetings. Discussions about how Tools should be present on the libraries pages. On the DB servers, adjusted postgresql authentication configurations from md5 to scram-sha-256 on all databases and multiple ansible roles. Actually this turns out to be a superficial change even though it should be done. The reason is that newer postgres will use scram-sha-256 behind-the-scenes regardless. Wrote deploy-qa.sh, a script to enable metalab QA engineers to deploy a pull request onto a test server. The precise git SHA commit of any open pull request can be tested. Wrote upload-images.sh, a script to store Bob Ostrom’s boost cartoons in S3 instead of the github repo. Mailman3 Synced production lists to the staging server. Wrote a document in the cppalliance/boost-mailman repo explaining how the multi-step process of syncing can be done. boostorg Migrated cppalliance/decimal to boostorg/decimal. Jenkins The Jenkins server is building documentation previews for dozens of boostorg and cppalliance repositories where each job is assigned its own “workspace” directory and then proceeds to install 1GB of node_modules. That was happening for every build and every pull request. The disk space on the server was filling up, every few weeks yet another 100GB. Rather than continue to resize the disk, or delete all jobs too quickly, was there the opportunity for optimization? Yes. In the superproject container image relocate the nodejs installation to /opt/nvm instead of root’s home directory. The /opt/nvm installation can now be “shared” by other jobs which reduces space. Conditionally check if mermaid is needed and/or if mermaid is already available in /opt/nvm. With these modifications, since each job doesn’t need to install a large amount of npm packages the job size is drastically reduced. Upgraded server and all plugins. Necessary to fix spurious bugs in certain Jenkins jobs. Debugging Jenkins runners, set subnet and zone on the cloud server configurations. Fixed lcov jobs, that need cxxstd=20 Migrated many administrative scripts from a local directory on the server to the jenkins-ci repository. Revise, clean, discard certain scripts. Dmitry contributed diff-reports that should now appear in every pull request which has been configured for LCOV previews. Implemented –flags in lcov build scripts [–skip-gcovr] [–skip-genhtml] [–skip-diff-report] [–only-gcovr] Ansible role task: install check_jenkins_queue nagios plugin automatically from Ansible. GHA Completed a major upgrade of the Terraform installation which had lagged upstream code by nearly two years. Deployed a series of GitHub Actions runners for Joaquin’s latest benchmarks at https://github.com/boostorg/boost_hub_benchmarks. Installed latest VS2026. MacOS upgrade to 26.3. Drone Launched new MacOS 26 drone runners, and FreeBSD 15.0 drone runners.📝The C++ Alliance

Monday, March 30, 2026

Sunday, March 29, 2026

C++26 is done! — Trip report: March 2026 ISO C++ standards meeting (London Croydon, UK)News flash: C++26 is done! 🎉 On Saturday, the ISO C++ committee completed technical work on C++26 in (partly) sunny London Croydon, UK. We resolved the remaining international comments on the C++26 draft, and are now producing the final document to be sent out for its international approval ballot (Draft International Standard, or DIS) and … Continue reading C++26 is done! — Trip report: March 2026 ISO C++ standards meeting (London Croydon, UK) →📝Sutter’s Mill

Saturday, March 28, 2026

Friday, March 27, 2026

Statement from the C++ Alliance on WG21 Committee Meeting SupportThe C++ Alliance is proud to support attendance at WG21 committee meetings. We believe that facilitating the attendance of domain experts produces better outcomes for C++ and for the broader ecosystem, and we are committed to making participation more accessible. We want to be unequivocally clear: the C++ Alliance does not, and will never, direct or compel attendees to vote in any particular way. Our support comes with no strings attached. Those who attend are free and encouraged to exercise their independent judgment on every proposal before the committee. The integrity of the WG21 standards process depends on the independence of its participants. We respect that process deeply, and any suggestion to the contrary does not reflect our values or our program. If you are interested in learning more about our attendance program, please reach out to us at info@cppalliance.org.📝The C++ Alliance

Thursday, March 26, 2026

Wednesday, March 25, 2026

Windows Store Deployment with windeployqtMicrosoft introduced the Windows Store with Windows 8 as central place to download and update software. To place software into the Microsoft Store, developers must sign it digitally. Microsoft checks the Software before it is published into the Microsoft Store. The AppxManifest.xml describes the packaging information for the Microsoft Store. The makeappx tool creates the appx installer, which is signed with the signtool from the Windows SDK. With Qt 6.11, windeployqt got extra command line arguments to create an AppxManifest.xml , namely those are the --appx and --appx-certificate arguments.📝Qt Blog
Fast Remote Desktop (RDP) from macOS to WindowsI regularly use Windows’ Remote Desktop Protocol (RDP) to connect from a non-Windows client to a Windows host machine (e.g., from my MacBook Pro to my CAD/Gaming Desktop Tower PC) to access software otherwise not available on Linux or macOS (mostly CAD/eCAD software like SolidWorks or Altium Designer). Unfortunately, by default the Remote Desktop client application from Micro$oft has terrible performance issues, especially when connecting from macOS to Windows. However, with a little bit of tweaking on the host and switching from the Remote Desktop Client (nowadays just called “Windows App”) to FreeRDP (or any alternative that is using FreeRDP under the hood) we can make the performance and visual fidelity bearable. Changes on the Host On the host machine, make sure to use an updated Windows. Open the “Group Policy Editor” and navigate to: Computer Configuration > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host Under “Remote Session Environment” configure the following policies: “Use hardware graphics adapter for all Remote Desktop Service sessions” Enabled “Prioritize H.264/AVC 444 graphic mode for Remote Desktop Connections” Disabled “Configure H.264/AVC hardware encoding for Remote Desktop Connections” Enabled Under Connections configure the following policies: “Select RDP transport protocols” Enabled with Use either UDP or TCP Reboot the host machine. Changes on the Client Meanwhile, download, and install Royal TSx for macOS . Install the Remote Desktop plugin, and create a new connection. Make sure to set the following options: Under Display Options Set Colors to High Color (15 Bit) Uncheck Use full retina resolution Set Scale Factor to 100% Set Desktop Size to Auto Expand Set Resize Mode to Smart Reconnect Under Performance Chose LAN as Connection Speed Uncheck all but Graphics Pipeline and Font Smoothing Configure the remaining settings as you prefer. Now, you can connect to a Remote Desktop session that has acceptable performance and doesn’t look like Godzilla vomited all over your screen.📝Arvids Blog