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 Benchmarking Platform
Phoromatic Test Orchestration

DragonEgg-ing Mesa & Banging It With Clang

Michael Larabel

Published on 8 December 2011
Written by Michael Larabel
Page 1 of 3 - 4 Comments

What happens if you build Mesa/Gallium3D with LLVM's Clang compiler or the LLVM DragonEgg plug-in with GCC? It has been asked before, so here is an answer.

With the recent release of LLVM 3.0 and respective updates for the Clang C/C++ compiler front-end and a much-improved DragonEgg plug-in for GCC, I decided to see whether these alternatives to the GNU Compiler Collection would now play well with Mesa/Gallium3D. When attempting to build out Mesa with earlier versions of LLVM, there were show-stopping problems.

This time around when building out Mesa, namely using the "make linux-llvm" option for building the Mesa/Gallium3D with the LLVMpipe driver to test the software acceleration on the CPU, things worked out when using LLVM/Clang/DragonEgg 3.0. There were no build errors and the generated binaries worked.

The only configuration where the Mesa build failed was when using GCC 4.6.2 with the DragonEgg plug-in from LLVM 3.0 while also passing the "-fplugin-arg-dragonegg-enable-gcc-optzns" switch that is meant for delivering "ultimate performance" by combining the LLVM and GCC optimizers. However, DragonEgg on GCC 4.6 without any extra optimizations had built a working Mesa stack along with Clang.

I also tried building the mainline Linux kernel (3.2 Git) using LLVM/DragonEgg 3.0, but that failed when it came to hitting some unsupported Assembly. A year ago, LLVM's Clang compiler hit the milestone of building the Linux kernel (well, most of it) but it required out-of-tree patches and other changes. That work still has not landed in mainline to allow Clang to build a vanilla kernel nor has the Clang Linux kernel source code on the GitHub project page been updated since this past May.

Latest Articles & Reviews
  1. Sub-$20 802.11n USB WiFi Adapter That's Linux Friendly
  2. The Lenovo T450s Is Working Beautifully With Linux
  3. Linux 4.0 SSD EXT4 / Btrfs / XFS / F2FS Benchmarks
  4. Linux 4.0 Hard Drive Comparison With Six File-Systems
  5. Lenovo ThinkPad T450s Broadwell Preview
  6. How Open-Source Allowed Valve To Implement VULKAN Much Faster On The Source 2 Engine
Latest Linux News
  1. GCC 5.1 RC2 Arrives, GCC 5.1 Planned For Next Week
  2. F2FS For Linux 4.1 Has New Features & Fixes
  3. Phoronix Server Upgrade This Weekend: Dual Haswell Xeons, 96GB DDR4
  4. Google's Experimental QUIC Transport Protocol Is Showing Promise
  5. Red Hat Joins Khronos, The Group Behind OpenGL & Vulkan
  6. NetworkManager Drops WiMAX Support
  7. Wine 1.7.41 Works More On Kernel Job Objects, MSI Patches
  8. Linux 4.1 Has Improvements For The Multi-Queue Block Layer
  9. X.Org Looks To Have Six Summer Projects
  10. DragonFlyBSD Pulls In GCC 5 Compiler
Most Viewed News This Week
  1. Nouveau: NVIDIA's New Hardware Is "VERY Open-Source Unfriendly"
  2. Linux 4.0 Kernel Released
  3. Microsoft Announces An LLVM-Based Compiler For .NET
  4. Linux 4.1 Brings Many Potentially Risky x86/ASM Changes
  5. Encryption Support For EXT4
  6. VirtualBox 5.0 Beta 2 Released
  7. Mozilla Start Drafting Plans To Deprecate Insecure HTTP
  8. Elementary OS 0.3 "Freya" Now Available