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LLVM Weekly - #113, Feb 29th 2016

Welcome to the one hundred and thirteenth 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.

News and articles from around the web

LLVM and Clang 3.8RC3 has been tagged.

EuroLLVM 2016 is less than a month away. If you want to attend, be sure to register.

The Red Hat blog has a summary of new features in the upcoming GCC 6 release.

The Meeting C++ blog has a helpful summary of a subset of the proposals for the next C++ committee meeting.

On the mailing lists

LLVM commits

  • The Sparc backend now contains definitions for all registers and instructions defined in the Sparc v8 manual. r262133.

  • LLVM gained a basic LoopPassManager, though it currently only contains dummy passes. r261831.

  • A number of TargetInstrInfo predicates now take a reference to a MachineInstr rather than a pointer. r261605.

  • The WebAssembly backend gained redzone support for the userspace stack. r261662.

Clang commits

  • Whole-program vtable optimisation is now available in Clang using the -fwhole-program-vtables flag. r261767.

  • Clang gained __builtin_canonicalize which returns the platform-specific canonical encoding of a floating point number. r262122.

  • A hasAnyName matcher was added. r261574.

  • The pointer arithmetic checker has been improved to report fewer false positives. r261632.

Other project commits

  • The new ELF linker gained support for identical code folding (ICF). This reduces the size of an LLD binary by 3.6% and of a Clang binary by 2.7%. As described in the commit message, this is not a "safe" version of ICF as implemented in GNU gold, so will cause issues if the input relies on two distinct functions always having distinct addresses. r261912.

  • Polly's tree now contains an script that may be useful to other LLVM devs. It updates a FileCheck-based lit test by updating the CHECK: lines with the actual output of the RUN: command. r261899.

  • LLDB gained a new set of plugins to help debug Java programs, specifically Java code JIT-ed by the Android runtime. r262015.

  • The new OpenMP 4.5 affinity API is now supported in LLVM's openmp implementation. r261915.

  • The new ELF linker gained support for the -r command-line option, which produces relocatable output (partial linking). r261838.

  • The CMake/lit runner for SPEC in the LLVM test-suite can now run the C CPU2006 floating point benchmarks (but not the Fortran ones). r261816.

  • The old ELF linker has been deleted from LLD. r262158.