LLVM Weekly

LLVM Weekly - #669, October 26th 2026. LLVM and MLIR FOSDEM devrooms CfPs, debuginfo API changes, -fspatial-safety C++ proposal, library layering of Clang Parser and Sema, removing LLDB's GUI mode, and more. llvmweekly.org/issue/669

LLVM Weekly - #668, October 19th 2026. Static memory planner for MLIR, LLVM Memory Safety Workshop, fpconvert, LoopFusion cost model, Flang inline runtime check operations, LLVM libc on Hexagon, and more llvmweekly.org/issue/668

LLVM Weekly - #667, October 12th 2026. Improving lit, last chance to register for LLVM Dev Meeting 2026, Women in Compilers and Tools meetup, ClangIR support built by default RFC accepted, LLDB debugserver in Swift, testing LLDB WebAssembly support, and more llvmweekly.org/issue/667

LLVM Weekly - #666, October 5th 2026. Sharing floating point routine implementations between libc and compiler-rt, EDG C++ frontend open sourced, September ClangIR progress report, forbidding AI generated communication, GitHub issues making merging difficult, and more. llvmweekly.org/issue/666

LLVM Weekly - #665, September 28th 2026. Remembering Johannes Doerfert. Also: Wasm externref support, LLVM Foundation board minutes, bitinsert/bitextract, Flang -finit-local, and more. llvmweekly.org/issue/665

Remembering Johannes Doerfert: "It is with great sadness that we share the news of the passing of Johannes Doerfert. [...] Johannes was one of the most prolific and respected contributors to the LLVM compiler project, and his loss will be deeply felt." blog.llvm.org/posts/2026-0...

LLVM Weekly - #664, September 21st 2026. Improving HLSL support in clangd, linker I/O tricks and their downsides, SuperH backend, BRay - tracing with BOLT, AMDGPU UndefinedBehaviorSanitizer, copy profiler, and more llvmweekly.org/issue/664

LLVM Weekly - #663, September 14th 2026. GSoC Clang API notes project report, MLIR project lighthouse update, MLIR news, -fkeep-inline-functions, Fortran LLDB plugin, and more llvmweekly.org/issue/663

LLVM Weekly - #662, September 7th 2026. Proposed contributor policy refresh, AGENTS .md, building ClangIR by default, nanoMIPS upstreaming, deleting the ExecutionEngine interpreter, DirectX an official backend, and more llvmweekly.org/issue/662

LLVM Weekly - #661, August 31st 2026. LLVM 23.1.0 released, changing MachineIR to use block arguments instead of PHIs, August ClangIR progress, and more. llvmweekly.org/issue/661

LLVM Weekly - #660, August 24th 2026. Compile-time improvements in LLVM 23, LNT v5 proposal, Xtensa LLD support, cpp-bounded-buffers source transformation, and more. llvmweekly.org/issue/660

LLVM Weekly - #659, August 17th 2026. Promoting the DirectX backend to an official backend, SortedVectorMap, ClangIR alias analysis, gathering historical libcxx benchmark data, and more. llvmweekly.org/issue/659

LLVM Weekly - #658, August 10th 2026. LLVM Developers' Meeting program announced, upstreaming the Intel PISA (virtual ISA for GPUs) backend, moving LLDB away from TypeSystemClang, MLIR newsletter returns, dynamic debugging, and more llvmweekly.org/issue/658

LLVM Weekly - #657, August 3rd 2026. Enabling the new pass manager for codegen, when is it worthwhile adding a new intrinsic, byte type support in llubi, new LLVM libc logo, IR Outline removed, Furo theme now used for LLVM docs, and more llvmweekly.org/issue/657

LLVM Weekly - #656, July 27th 2026. Improving HLSL support in clangd, -fdefined-pointer-subtraction, documenting LLDB platform/target support requirements, raising WASM MLIR to other dialects, and more llvmweekly.org/issue/656

LLVM Weekly - #655, July 20th 2026. LLVM 23.x branched, July ClangIR progress report, DS2 debug server, SpacemiT-X100 (RISC-V RVA23U64) LNT perf tracking now live, Templight removed, and more llvmweekly.org/issue/655

LLVM Weekly - #654, July 13th 2026. llvm-ub-aware-interpreter update, x86-64 Lightweight Fault Isolation, LangRef rewritten in Markdown, x86-64 ABI implemented in LLVM's new ABI library, MS contributed exception_ptr, and more llvmweekly.org/issue/654

LLVM Weekly - #653, July 6th 2026. LLVM in CACM, impact of template use of Flang's compile times, 23.x branching next week, alternative std::vector representation, and more llvmweekly.org/issue/653

LLVM Weekly - #652, June 29th 2026. EuroLLVM 2026 recordings now available, optimising LLVM's bump allocator, revisiting commit access criteria, Wasm reference types as target extension types, building flang with PGO and BOLT, and more llvmweekly.org/issue/652

LLVM Weekly - #651, June 22nd 2026. US LLVM Dev Meeting call for papers + registration + student travel grant applications all open, allocator provenance model, ClangIR upstreaming update, CopySanitizer, llvm.pext/llvm.pdep, parallel DWARF processing in BOLT, and more llvmweekly.org/issue/651

LLVM Weekly - #650, June 15th 2026. Seeking new LLVM Foundation board members, AI review of PRs, linking massive binaries in LLD, Hygon X86 processors, Windows x64 unwind v3, SpacemiT X60 scheduling model now default for RISC-V, and more llvmweekly.org/issue/650

LLVM Weekly - #649, June 8th 2026. Improvements to LLVM's hash table implementations, MLIR token type, breaking the Python revlock, migrating docs to Markdown, parallel DWARF linker, and more llvmweekly.org/issue/649

LLVM Weekly - #648, June 1st 2026. Call for LLVM Dev Meeting workshops, BorrowSanitizer, Apple Metal/AIR backend, MC layer RVY (CHERI), DEC Alpha support added to libsanitizer(!), and more. llvmweekly.org/issue/648

LLVM Weekly - #647, May 25th 2026. Importance of open access to ISO standards documents, reST => Markdown?, 32-bit RISC-V support in BOLT, and more llvmweekly.org/issue/647

I've blogged about Qt Creator 20 and the faster clangd at: www.qt.io/blog/qt-crea...

LLVM Weekly - #646, May 18th 2026. New strict FP proposals, OpenACC runtime, AArch64 code layout optimisations, C1-Nano scheduling model, misc-static-initialization-cycle clang-tidy check, Tel Aviv / Portland / Berlin LLVM meetups, and more llvmweekly.org/issue/646

LLVM Weekly - #645, May 11th 2026. 22.1.5, May ClangIR upstreaming report, parallel DWARF processing in BOLT, C1-Premium scheduling model, Instrumentor pass, clang-ssaf-analyzer, -fexperimental-abi-lowering, and more. llvmweekly.org/issue/645

LLVM Weekly - #644, May 4th 2026. GSoC 2026 started (congratulations and welcome to all new contributors!), US LLVM dev meeting PC volunteers, draft LLVM moderation guide, MLIR token type, and more llvmweekly.org/issue/644

LLVM Weekly - #643, April 27th 2026. EuroLLVM slide decks available, Vulkan-style memory model, 22.1.4, improving function size estimation for Arm, -fstrict-bool, and more. llvmweekly.org/issue/643

LLVM Weekly - #642, April 20th 2026. EuroLLVM roundtable notes, ClangIR upstreaming status update, Arm C1-Ultra scheduling model, SerenityOS, and more llvmweekly.org/issue/642

LLVM Weekly - #641, April 13th 2026. See some of you at EuroLLVM! Tracking down and fixing a performance regression, LLD ELF performance improvements, LLVM Foundation DevOps Infra Engineer, llvm-testing-tools package for FileCheck and split-file, and more. llvmweekly.org/issue/641

LLVM Weekly - #640, April 6th 2026. The role of a maintainer, maintainer workload + AI generated fixes, RVCC incubator proposal, JSIR a high-level MLIR-based IR for JavaScript, and more llvmweekly.org/issue/640

LLVM Weekly - #639, March 30th 2026. C++26 is complete, clang-reforge for rewriting codebases for bounds safety, unity builds, DAG combine topological sorting, tailcalls for Clang's bytecode interpreter implementation, and more llvmweekly.org/issue/639

LLVM Weekly - #638, March 23rd 2026. Better frontend benchmarks, Scudo allocator in LLVM libc, byte type in LLVM IR, endian.h, modular printf, and more llvmweekly.org/issue/638

LLVM Weekly - #637, March 16th 2026. 22.1.1 released, so many meetups, RISC-V ropi-rwpi, Br replaced with UncondBr/CondBr, modernize-use-std-bit checker, and more llvmweekly.org/issue/637

LLVM Weekly - #636, March 9th 2026. Template for out-of-tree MLIR optimiser projects, LLVM Research Library, proposed new docs theme, --cstdlib, clang-tidy performance-user-std-move, and more llvmweekly.org/issue/636

LLVM Weekly - #635, March 2nd 2026. LLVM 22.1.0 released, guidance for GSoC 2026 applicants, status of GISel by default for AArch64, bugpoint deleted, and more llvmweekly.org/issue/635

LLVM Weekly - #634, February 23rd 2026. Chris Lattner on the Claude C Compiler, LLVM Foundation board meeting minutes, LLDB accelerator support, removing bugpoint, TSan adaptive delay scheduling, LLDB tree-sitter Swift+Rust syntax highlighting, and more llvmweekly.org/issue/634

LLVM Weekly - #633, February 16th 2026. Area team election results, EuroLLVM early bird pricing ending soon, a long-term vision for improving LLVM build times, SpacemiT X100 scheduling model, clang::no_outline and more llvmweekly.org/issue/633

LLVM Weekly - #632, February 9th 2026. Final day to vote in LLVM area team elections, Hexagon-MLIR open sourced, IR outliner, lots of meetups, WebAssembly GlobalISel, ^^ reflection operator, and more llvmweekly.org/issue/632

LLVM Weekly - #631, February 2nd 2026. GSoC ideas, Scalable Static Analysis Framework linker, MIPS R5900 (PS2 Emotion Engine) support, lots of documentation additions, and more llvmweekly.org/issue/631

LLVM Weekly - #630, January 26th 2026. EuroLLVM registration open, LLVM community area team election voting about to start, more RISC-V LLVM performance improvements, LLVM IR byte type, a flurry of LLVM IR intrinsic additions or changes, and more llvmweekly.org/issue/630

LLVM Weekly - #629, January 19th 2026. Nominations for area team elections open, LLDB developments in 2025, 22.x branched, "human in the loop" AI contribution policy, advanced symbol resolution for clang-repl, optimising conditional traps on x86-64, and more. llvmweekly.org/issue/629

LLVM Weekly - #628, January 12th 2026. 22.x branching tomorrow, LLVM: the bad parts, MLIR python bindings improvements, softPromoteHalfType default for backends, cross-compiling OpenCL libraries, and more llvmweekly.org/issue/628

Nikita Popov (who sadly isn't on Bluesky) has a great new post. LLVM: The bad parts www.npopov.com/2026/01/11/L...

LLVM Weekly - #627, January 5th 2026. Twelve years of LLVM Weekly, EuroLLVM CfP closing soon, GNU toolchain in 2025 summary, PCH to speed-up LLVM builds, LLVM ABI lowering library starting to land, and more llvmweekly.org/issue/627

LLVM Weekly - #626, December 29th 2025. Happy holidays! SFrame feedback, restrict progress, Nvidia Olympus AArch64 CPU scheduling model, libcxx rotate optimisations, and more. llvmweekly.org/issue/626

LLVM Weekly - #625, December 22nd 2025. FOSDEM LLVM dev room program, propeller profile conversion tool, AI tool policy, Arm C1 processors, Lightweight Fault Isolation upstreaming starts, and more llvmweekly.org/issue/625

LLVM Weekly - #624, December 15th 2025. Experience with [[clang:::musttail]], 2025 highlights for the MLIR vector dialect, -fdevirtualize-speculatively, closing the perf gap between RISC-V LLVM and GCC part 1, and more llvmweekly.org/issue/624

Does LLVM produce slower RISC-V code than GCC? Currently, yes. Can we make LLVM produce faster code? Also, yes! lukelau.me/2025/12/10/c... #llvm #riscv