LLVM Weekly - #645, May 11th 2026

Welcome to the six hundred and forty-fifth 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 via email: asb@asbradbury.org, or Mastodon: @llvmweekly@fosstodon.org / @asb@fosstodon.org, or Bluesky: @llvmweekly.org / @asbradbury.org.

I’ve written up the recipes I use to build 32-bit RISC-V sysroots with Yocto for LLVM cross compilation and testing.

According to the LLVM Calendar in the coming week there will be the following:

Office hours with the following hosts: Aaron Ballman, Alexey Bader, Alina Sbirlea, Kristof Beyls, Johannes Doerfert.
Online sync-ups on the following topics: Flang, alias analysis, qualification, modules, libc++, lifetime safety, LLVM/Offload, OpenMP for flang, HLSL, memory safety, reflection.
For more details see the LLVM calendar, getting involved documentation on online sync ups and office hours.

LLVM 22.1.5 was released.
Bruno Cardoso Lopes posted the May ClangIR upstreaming progress report.
Pedro Vicente and Guilherme Lopes started an RFC thread on bitinsert and bitextract instructions for LLVM IR which woud be used for extracting or inserting contiguous ranges of bits in the new byte type.
JinRui Shi proposed a new parallel DWARF processing approach in BOLT.
Aman LaChapelle and Walter Erquinigo started an RFC thread on interpreted binary interactive debugging, which aims to help debugging programs written in e.g. mixed Python and native C/C++.
Charles Zablit suggested switching from libedit to replxx in LLDB.

A scheduling model was added for the Arm “C1-Premium”. a3c18c0.
The require-logical-module flag can be used to require the use of logical alloc/gep instructions. 9fe04e0.
The elementwise modifier can now be used with atomicrmw. 239ca8d.
The LangRef now documents the expected layout for patchable-function-entry and patchable-function-prefix attributes. 6e27684.
MC layer support was added for the experimental RISC-V Zvvmm integrated matrix extension. a8b0124.
The LoopFusion pass was documented. cb15e67.
The initial infrastructure for the Instrumentor pass was committed. 7b4175c, c507e20.
Developer guidelines were added for the AMDGPU backend. f996fa2.
MC layer support was added for WebAssembly’s typed select instruction. 82b2aeb.
The 2026 Security Response Group Transparency report is now available. 143aa41.

The clang-ssaf-analyzer tool was introduced, which can run whole program analysis over an ‘LUSummary’. 51d2a66.
Infrastructure was added for NVPTX builtins in ClangIR. 8a4f8ba.
As part of Thread Safety Analysis, attributes can now be put on function pointers. d1e84bb.
Through -fexperimental-abi-lowering, the LLVMABI function call ABI lowering can be used. 07b5dfe.

BOLT’s gadget scanner documentation was updated. 25deb6e.
A basic dl_iterate_phdr implementation was added to LLVM libc. a1d21cc.
PIC/dynamic linking is no longer marked as experimental in the Wasm linker. d063eeb.
Instructions were added for debugging the LLDB VSCode extension. 31d1ce8.
A more complex mlir-reduce example was added to the documentation. 6a9c3b6.