1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Building Linux With LLVM/Clang Excites The Embedded World

Compiler

Published on 09 March 2013 04:25 PM EST
Written by Michael Larabel in Compiler
39 Comments

Building the Linux kernel with LLVM/Clang rather than GCC continues to be a big focus within the embedded Linux community.

Qualcomm among other ARM vendors have been interested in building the Linux kernel with LLVM/Clang. It's possible to build kernels with this alternative open-source C/C++ compiler, but out-of-tree patches are currently required to the Linux kernel and not everything works smoothly. There's a long TODO list until everything is polished and LLVM/Clang becomes a first-class compiler for the Linux kernel, but the effort was formalized last year with the LLVMLinux project that is hosted by the Linux Foundation.

Among the reasons people continue to be interested in using Clang over GCC is the cleaner and easier to work with code-base of the compiler, compilation times are often faster while using less RAM, there's an assortment of static analysis tools and other useful benefits over GCC, and the compiler is under a BSD-style license.

Developers also are pushing the Linux kernel -- and other key software packages -- through Clang since it leads to more portable code by pushing it through more compilers. Among the challenges that the LLVM Linux project has faced is GCC defaulting to using GNU89 of the C language while Clang defaults to GNU99, the kernel using undocumented GCC behavior, unsupported GCC flags, and Kconfig being GCC-specific.

The state of building the Linux kernel with Clang was talked about last month at the Linux Foundation's Embedded Linux Conference 2013. Embedded below is the video of the talk. For those curious about the state of not using GCC to build the Linux kernel, visit the LF project site.

The good news shared during the presentation is that LLVM/Clang 3.3 will likely work "mostly out-of-the-box" for the Linux kernel, albeit patches are still required on the kernel side. (Right now about four patches are require to upstream LLVM/Clang for x86_64 Linux support.)

Slides of the ELC 2013 presentation can be found on Google Docs.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. Intel Xeon E5-1680 v3 & E5-2687W v3 Compared To The Core i7 5960X On Linux
  2. Intel 120GB 530 Series SSD Linux Performance
  3. Btrfs/EXT4/XFS/F2FS RAID 0/1/5/6/10 Linux Benchmarks On Four SSDs
  4. AMD's Windows Catalyst Driver Remains Largely Faster Than Linux Drivers
Latest Linux Articles
  1. NVIDIA vs. Nouveau Drivers With Linux 3.18 + Mesa 10.4-devel
  2. Is The Open-Source NVIDIA Driver Fast Enough For Steam On Linux Gaming?
  3. Linux 3.18 File-System Performance Minimally Changed But Possible Regressions
  4. AMD Radeon Gallium3D Is Catching Up & Sometimes Beating Catalyst On Linux
Latest Linux News
  1. Scientific Linux 6.6 vs. Scientific Linux 7.0 Benchmarks
  2. Qualcomm Looks To Get Into The ARM Server Business
  3. HHVM 3.4 Adds New Features, Support
  4. More Radeon Driver Changes Queued For Linux 3.19
  5. Unigine 2.0 Alpha 2 Adds C# Support
  6. FFmpeg Is Returning To Ubuntu With 15.04 Release
  7. Linux Version Of Civilization: Beyond Earth Still Coming Along
  8. Yahoo To Become Default Search Provider For Firefox
  9. Better Fan Control Support Coming To The Open-Source Radeon Driver
  10. PTS 5.4 Milestone 6 Released - Official "Lipki" Release Is Near
Latest Forum Discussions
  1. Debian Developer Resigns From The Systemd Maintainership Team
  2. Debian Init System Coupling Vote Results
  3. Updated and Optimized Ubuntu Free Graphics Drivers
  4. Ubuntu Developers Still Thinking What To Do About Adobe Flash Support
  5. How to get rid of Linux
  6. how to configure module phoromatic ?
  7. Major Performance Breakthrough Discovered For Intel's Mesa Driver
  8. Script for Fan Speed Control