C++

Linux Code of Conduct to Get Updates

Code of Conduct was designed to establish the rules and boundaries of relationships between developers of Linux
22 October 2018   1436

In September 2018, the Linux-community was presented with a Code of Conduct (CoC) - a set of rules governing interpersonal relations between employees and aimed at preventing conflicts on the basis of disagreements during the work process. Although the document seemed quite controversial to the public, its immediate changes were not expected until the release of the stable version of the Linux kernel 4.19. Greg Kroa-Hartman, the accompanying Linux kernel developer, based on the feedback and complaints of his employees, combined them and outlined the most important ideas for changing the CoC.

One of the main proposals was the development of a document explaining some details of the CoC. Innovations also require employees in the event of a controversial situation to apply now to the Code of Conduct Committee, rather than to the Linux Foundation Technical Advisory Board.

Another important update is the emergence of a mediator in Linux kernel conflicts. SFLC’s legal director, Misha Chowdhary, was appointed to this position.

The remaining changes can be viewed in the archive of developers of the Linux kernel. It is expected that the innovations will be implemented with the release of the stable Linux kernel version 4.19.0. The developers also created a CoC webpage.

CoC is designed to establish the rules and boundaries of relationships between developers of Linux. Linus Torvalds established the Code of Conduct and explained the decision by the fact that it is impossible to objectively reach a common decision in the discussion on norms of behavior.

C++

LLVM 10.0.0 to be Released

New version of the popular development toolkit brings, among other things, support for the C++ Concepts
26 March 2020   948

After six months of development, the release of the LLVM 10.0 project, a GCC-compatible toolkit (compilers, optimizers, and code generators), compiling programs into an intermediate bitcode of RISC-like virtual instructions (a low-level virtual machine with a multi-level optimization system), is presented. The generated pseudo-code can be converted using the JIT compiler into machine instructions directly at the time of program execution.

Among the new features of LLVM 10.0, there are support for C ++ Concepts (C ++ Concepts), termination of the launch of Clang in the form of a separate process, support for CFG checks (control flow guard) for Windows, and support for new CPU features.

The main innovations of LLVM 10.0:

  • New interprocedural optimizations and analyzers have been added to the Attributor framework. The prediction of the state of 19 different attributes, including 12 attributes of 12 LLVM IR and 7 abstract attributes such as liveness, is provided.
  • New built-in compiler matrix mathematical functions (Intrinsics) have been added, which, when compiled, are replaced by effective vector instructions.
  • Numerous improvements to the backends for the X86, AArch64, ARM, SystemZ, MIPS, AMDGPU, and PowerPC architectures. Added support for Cortex-A65, Cortex-A65AE, Neoverse E1 and Neoverse N1 CPUs. For ARMv8.1-M, ​​the code generation process has been optimized (for example, support for loops with minimal overhead has appeared) and support for auto-vectorization using the MVE extension has been added. Improved support for CPU MIPS Octeon. PowerPC includes vectorization of mathematical routines using the MASSV (Mathematical Acceleration SubSystem) library, improved code generation, and optimized memory access from loops. For x86, the processing of vector types v2i32, v4i16, v2i16, v8i8, v4i8 and v2i8 has been changed.
  • Improved code generator for WebAssembly. Added support for TLS (Thread-Local Storage) and atomic.fence instructions. Significantly expanded support for SIMD. WebAssembly object files added the ability to use function signatures with multiple values.
  • When processing cycles, the MemorySSA analyzer is used to determine the dependencies between different memory operations. MemorySSA can reduce compilation and execution time, or can be used instead of AliasSetTracker without sacrificing performance.
  • The LLDB debugger has significantly improved support for the DWARF v5 format. Improved build support with MinGW and added the initial ability to debug Windows executable files for ARM and ARM64 architectures. Added descriptions of options offered when autocompleting input by pressing tabs.
  • Enhanced LLD Linker Features. Improved support for the ELF format, including full compatibility of glob templates with the GNU linker, added support for the compressed debug sections ".zdebug", added the PT_GNU_PROPERTY property to determine the .note.gnu.property section (can be used in future Linux kernels), implemented modes "-z noseparate-code", "-z separate-code" and "-z separate-loadable-segments". Improved support for MinGW and WebAssembly.

Get more at the release notes.