LLVM Weekly - #304, October 28th 2019

Welcome to the three hundred and fourth issue of LLVM Weekly, a weekly newsletter (published every Monday) covering developments in LLVM, Clang, and related projects. LLVM Weekly is brought to you by Alex Bradbury. Subscribe to future issues at https://llvmweekly.org and pass it on to anyone else you think may be interested. Please send any tips or feedback to asb@asbradbury.org, or @llvmweekly or @asbradbury on Twitter.

News and articles from around the web

The 2019 LLVM Dev Meeting took place in San Jose last week and was a huge success. 630 attendees, a 17.5% growth in attendance vs last year. It was the Largest program yet with 2 keynotes, 26 technical talks, 11 tutorials, 2 panels, 4 BofS, 4 Student Research Competition presentations, 23 lightning talks and 31 proposed roundtables. Thanks to the organisers, sponsors, speakers, and attendees.

The migration from SVN to a git repo hosted by GitHub is now complete. Many thanks to Tom Stellard and everyone else involved in this effort. LLVM Weekly now uses git short hashes to refer to commits.

On the mailing lists

• James Y Knight kicked off an RFC thread on switching from Bugzilla to GitHub issues. Although there is plenty of interest, there are also a number of challenges to be resolved. Anton Korobeynikov created a doc to collect them.

• Siva Chandra has posted a v2 of the proposal for "ground truth files" for libc. It now uses TableGen rather than Python.

• Chris Bieneman shared an RFC on future directions for the LLVM build system. The proposal identifies that the build system is evolving in divergent ways and in places is more complex than it needs to be. He proposes a number of concrete changes to improve the situation.

• John McCall has shared an RFC on pointer authentication for arm64e, announcing that Apple would like to upstream their implementation for LLVM, Clang, and Swift.

• Hans Wennborg announces that a tag llvmorg-10-init has been created to mark "the initial commit with major version number 10". git describe can now be used to create names like llvmorg-10-init-8348-ga4783ef58d3.

• Thomas Preud'homme wonders if anyone has any FileCheck feature requests / wishlist items.

• David Greene has shared v3 of his LLVM complex types proposal.

• Gábor Márton summarises discussion at the ASTImporter round table at the LLVM Dev Meeting.

• Dmitriy Borisenkov penned an RFC on non 8-bit bytes in LLVM. David Chisnall asks for further clarification about the needs of the TON target.

LLVM commits

• The Arm backend started to gain IR intrinsics for MVE instructions. 1b45297, ceeff95.

• The git-llvm script now pushes to github. 3bf7fdd.

• The GlobalISel documentation has been restructured. feab033.

• The RISC-V backend gained support for -ffixed-xX flag for reserving GPRs. aed9d6d.

Clang commits

• Implementation of C++20 concepts continues with the addition of constraint enforcement and diagnostics. ffa214e.

• clang-objc-fuzzer was introduced. e5ecba4.

• C++20 support for explicitly defaulted comparison functions was added. d052a578.

• Initial intrinsics were implemented for Arm MVE. 08074cc.

Other project commits

• LLDB gained initial support for Arm register contexts on Windows. a59444a.

• It's now possible to build the sanitizers for RISC-V 64-bit. 977205b.