LLVM Weekly - #660, August 24th 2026

Welcome to the six hundred and sixtieth 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.

News and articles from around the web and events

Alexis Engelke blogged about compile-time improvements in LLVM 23.

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

• Office hours with the following hosts: Kristof Beyls, Amara Emerson.
• Online sync-ups on the following topics: Formal specification, pointer authentication, OpenMP, Flang, RISC-V, LLVM libc, HLSL, LLVM libc math.
• For more details see the LLVM calendar, getting involved documentation on online sync ups and office hours.

On the forums

• Louis Dionne proposed a major rework of LNT (LNT v5).

• Fangrui Song posted a detailed RFC on teaching RegAllocFast to consume SSA MachineIR directly, dropping PHIElimination and TwoAddressInstructionPass from the pipeline. This improved codegen time by ~4.5% for lld/ELF/Driver.cpp.

• Simeon Schaub is looking to change the i128 datalayout default to match Clang.

• Peter Smith started a discussion on a policy to move the default version of -fbinutils-version forward.

• Tom Eccles started a Flang RFC discussion on enabling a reassociation of some floating point expressions by default.

• Kazu Hirata proposed moving llvm::FoldingSet<T> to an open-addressing hash set.

• Alexey Gerenkov shared an RFC on Xtensa support in lld/ELF.

LLVM commits

• Trivial vector prediction (VP) intrinsics were removed. ad9138f.

• TargetOption::FloatABIType was removed, replaced fully by the float-abi module flag. 7e0416d.

• The elementwise modifier can now be used on atomic loads and stores. 7baba22.

• The mysteriously named Float8E5M4FNU format is now supported in convert.{to,from}.aribtary.fp. 9353edd.

• Some fixes were made to the documentation on writing a new backend. 39f2142.

• The target-abi module flag was documented. 077ec54.

Clang commits

• The cpp-bounded-buffers source transformation was added, which will rewrite raw pointers and arrays into bounded types. 2f4a2d5.

• [[clang::lifetime_capture_by(X)]] can now be used for plain structs and containers like std::vector. a14f953.

• The __builtin_type_order intrinsic was implemented. 0085ac9.

Other project commits

• freopen was implemented in LLVM libc. e297b4f.

• LLDB formatters were added for pretty printing MSVC STL std::expected, std::valarray, and std::source_location. 9a9b501, b8193ac, d952ddc.

• The strict property assembly format was enabled for various MLIR dialects. d2391bc, eb5ce30, 247df97, and more.