GNU News Archives


967 GNU open-source and Linux related news articles on Phoronix since 2006.

GCC 12 Profile Guided Optimization Benchmarks With The AMD Threadripper 3990X
GCC 12 Profile Guided Optimization Benchmarks With The AMD Threadripper 3990X

Last month I ran a number of GCC 12 compiler optimization benchmarks for this latest-stable compiler atop an AMD Ryzen Threadripper 3990X workstation. Those tests included various optimization levels as well as link-time optimizations (LTO). Some Phoronix Premium supporters also requested to see some fresh GCC 12 Profile Guided Optimization (PGO) benchmarks, so here in this article are those PGO benchmark results.

2 August 2022 - GCC 12 PGO Compiler Benchmarks - 40 Comments
GNU C Library Finally Adds arc4random Functions For Linux
GNU C Library Finally Adds arc4random Functions For Linux

The arc4random, arc4random_buf, and arc4random_uniform functions have been common on the BSDs for years to provide higher quality random number generation than rand/random and alternative functions. But now as of yesterday the GNU C Library (Glibc) has finally added the arc4random functions for use on Linux!

23 July 2022 - Glibc arc4random - 10 Comments
GCC-Rust Feedback Sought - Possibly Aiming For Upstream In GCC 13
GCC-Rust Feedback Sought - Possibly Aiming For Upstream In GCC 13

The Rust-GCC front-end that allows Rust code to be compiled with the GNU Compiler Collection (GCC) could possibly be upstreamed for next year's GCC 13 compiler release but not necessarily complete at that stage. In any case, it's good seeing progress on Rust-GCC as an alternative to Rust's official LLVM-based compiler.

27 June 2022 - GCC-Rust Upstreaming Talk - 50 Comments
Zhaoxin Tries Again To Upstream Their "LuJiaZui" CPU Support Within GCC
Zhaoxin Tries Again To Upstream Their "LuJiaZui" CPU Support Within GCC

Back in 2019 Chinese CPU company Zhaoxin introduced "LuJiaZui" as their 16nm x86 CPU design for use from laptops up through servers. LuJiaZui is much improved from their earlier chips though still well behind AMD and Intel performance. Proper GCC compiler support for LuJiaZui was sent out again this week after their previous upstreaming attempt hadn't made it into GCC 12 due to being late in the cycle.

22 May 2022 - Zhaoxin LuJiaZui - 4 Comments
GCC 12 Branched, Possible GCC 12.1 Stable Release Next Week
GCC 12 Branched, Possible GCC 12.1 Stable Release Next Week

The GCC 12 compiler code-base has reached zero P1 regressions (the highest priority) and thus the GCC 12 compiler code has been branched from mainline, a release candidate is imminent, and if all goes well GCC 12.1.0 as the stable release could be out as soon as the end of next week.

28 April 2022 - GCC 12 Status Report - Add A Comment
GCC 12 Compiler Gains Official Support For IBM z16
GCC 12 Compiler Gains Official Support For IBM z16

Over a year ago IBM sent out GCC compiler support for "arch14" that at the time we imagined was for IBM z16. Indeed with IBM having announced their z16 last week, the GCC compiler is now being updated to officially recognize z16 and offer that as an option over the "arch14" naming.

12 April 2022 - IBM z16 - 16 Comments
GCC 12 Still Has More Regressions To Stomp Before Release
GCC 12 Still Has More Regressions To Stomp Before Release

GNU Compiler Collection developers are working towards the stable release of GCC 12 in the next month or so as GCC 12.1. A GCC status report was issued today and there still is just under two dozen regressions of the highest priority (P1) to address or otherwise demote those regressions to lower priority.

4 April 2022 - GCC 12 Release Preparations - 6 Comments
LoongArch Port Merged For GCC 12

In continuation of last week's article that the GCC steering committee approved landing of LoongArch as a new port to this MIPS-derived Chinese CPU architecture, the code was merged on Tuesday.

30 March 2022 - Chinese MIPS-Derived CPU - 4 Comments
Zhaoxin Finally Adding "Lujiazui" x86_64 CPU Tuning To GCC
Zhaoxin Finally Adding "Lujiazui" x86_64 CPU Tuning To GCC

Introduced back in 2019 by the VIA + Shanghai owned Zhaoxin was the ZX-E / KX-6000 series x86_64 processors. Finally in 2022 the proper GCC compiler tuning support has been published for these processors that are part of the "Lujiazui" microarchitecture.

25 March 2022 - Zhaoxin lujiazui - 8 Comments
GNU Linux-Libre 5.17 Released For Free Software Purists

GNU Linux-Libre 5.17 is out as the downstream flavor of Linux 5.17 that strips out code/support depending upon closed-source microcode or other non-free fragments as well as removing the ability to load proprietary kernel modules.

22 March 2022 - GNU Linux-Libre 5.17 - 22 Comments
GNU/Hurd Continues Effort To Use NetBSD's Drivers For Better Hardware Support
GNU/Hurd Continues Effort To Use NetBSD's Drivers For Better Hardware Support

Besides all of the Linux-focused talks at the annual FOSDEM conference, another favorite track of mine is that on micro-kernels and other operating systems. While there wasn't the GNU/Hurd status update in 2022 as there has been in some recent years, there was a talk over GNU/Hurd using NetBSD kernel drivers in order to expand its hardware coverage.

6 February 2022 - Borrowing Drivers - 22 Comments
x86 Straight Line Speculation Mitigation Being Back-Ported To GCC 11
x86 Straight Line Speculation Mitigation Being Back-Ported To GCC 11

There sure has been a lot of x86 straight-line speculation happenings in recent months with the compiler-based mitigation being merged for GCC 12 and then beginning with Linux 5.17 the kernel can make use of that new knob for fending off this potential vulnerability. Now the compiler support is even being back-ported to GCC 11.

31 January 2022 - x86 SLS - 5 Comments
GCC 12 Ready To Help Fend Off Trojan Source Attacks
GCC 12 Ready To Help Fend Off Trojan Source Attacks

Disclosed a few months back were "Trojan Source" attacks against compilers where specially crafted code could be rogue but not appear so due to exploiting Unicode issues. Unicode control characters could be used to reorder tokens in source code that could alter the behavior when compiled. With the upcoming GCC 12 compiler release there is a new warning to help point out possible Trojan Source attacks.

16 January 2022 - -Wbidi-chars - 13 Comments
GCC 12 Shifting To Stage 4 Development - No Sign Of AMD Zen 4 Support
GCC 12 Shifting To Stage 4 Development - No Sign Of AMD Zen 4 Support

The GNU Compiler Collection (GCC) that serves as the default system compiler on most Linux distributions is nearing its annual update with GCC 12. GCC 12 has been in a general bug fixing period since November while beginning next week will be onto its final phase of focusing just on regression and documentation fixes to the compiler.

12 January 2022 - GCC 12 Stage 4, No Znver4 - 7 Comments
GNU Linux-libre 5.16 Brings More Firmware Cleansing, Deblobbing

Following yesterday's release of Linux 5.16, the GNU folks have released GNU Linux-libre 5.16-gnu as their downstream that removes/disables any code depending upon non-open-source firmware/microcode binaries, the ability to load proprietary kernel modules, and other cleaning in the name of free software.

10 January 2022 - GNU Linux-libre 5.16 - 14 Comments
Restartable Sequences "RSEQ" Support Returning To GNU C Library
Restartable Sequences "RSEQ" Support Returning To GNU C Library

Back in 2018 for the Linux 4.18 kernel was introducing the Restartable Sequences system call for allowing faster user-space operations on per-CPU data. By avoiding atomic operations in cases like incrementing per-CPU counters, modifying per-CPU spinlocks, reading/writing to per-CPU ring buffers, and similar, Restartable Sequences can provide a performance advantage. The GNU C Library is landing its revised support for making use of this system call.

10 December 2021 - Glibc + RSEQ - 4 Comments
Linux Prepares Straight Line Speculation "SLS" Mitigation For x86/x86_64 CPUs
Linux Prepares Straight Line Speculation "SLS" Mitigation For x86/x86_64 CPUs

Last month I reported on activity around Straight Line Speculation "SLS" mitigation for x86_64 CPUs, similar to the work carried out by Arm last year on their SLS vulnerability. That work on the x86 (x86_64 inclusive) side has now been merged to GCC 12 Git and a kernel patch is expected to come shortly that will flip it on as the latest CPU security protection.

18 November 2021 - Straight-Line Speculation - 1 Comment

967 GNU news articles published on Phoronix.