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LLVM Weekly - #127, June 6th 2016

Welcome to the one hundred and twenty-seventh 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 and pass it on to anyone else you think may be interested. Please send any tips or feedback to, or @llvmweekly or @asbradbury on Twitter.

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News and articles from around the web

Graham Markall at Embecosm has been comparing the code size of RISC-V binaries produced by the GCC and LLVM ports, as well as compared to ARM. GCC is currently ahead, though it is worth noting the LLVM port has seen much less attention.

Matthias Reisinger is a Google Summer of Code student working on enabling polyhedral optimisations for the Julia programming language. He's written a blog post detailing his initial steps and immediate future plans. Hopefully we'll see more posts over the summer.

Loïc Hamot has been working on a C++ to D converter, implemented using Clang.

The MSVC team have blogged about the latest release of Clang with Microsoft CodeGen, based on Clang 3.8.

There is going to be a clang-tidy code dojo in Warsaw on Tuesday the 7th of June.

On the mailing lists

LLVM commits

  • LLVM gained support for 'SJLJ' (setjmp/longjmp) exception handling on x86 targets. r271244.

  • LLVM now requires CMake 3.4.3 to build r271325.

  • Support was added for attaching metadata to global variables. r271348.

  • The AArch64 backend switched to use SubtargetFeatures rather than testing for specific CPUs. r271555.

Clang commits

  • The release notes have been updated to explain the current level of OpenMP support (full support of non-offloading features of OpenMP 4.5). r271263.

  • Clang's source-based code coverage has been documented. r271454.

Other project commits

  • An -fno-exceptions libc++abi library variant was defined, to match the -fno-exceptions libc++ build. r271267.

  • LLDB's compact unwind printing tool gained support for ARMv7's compact unwind format. r271744.