OSDT Weekly 第137期 · OSDT Weekly

近期活动

2月20日计划举办一场 GSoC 2022 线上讨论会，请感兴趣参加今年 GSoC 的同学记得关注明天的预告哦～

编译社区的八卦信息

C++ 动态新闻推送第 49 期 https://zhuanlan.zhihu.com/p/466351661

GCC

GCC12发布在即，core team处于bug fix状态，patch较少

计算所LoongArch GCC后端继续刷新 [PATCH v7 00/12] Add LoongArch support. https://gcc.gnu.org/pipermail/gcc-patches/2022-February/590294.html
[pushed 0/8] aarch64: Fix regression in vec_init code quality https://gcc.gnu.org/pipermail/gcc-patches/2022-February/590115.html
Benchmark recommendations needed https://gcc.gnu.org/pipermail/gcc/2022-February/238282.html
GNU toolchain老兵Maciej加入了Embecosm [PATCH v4][GCC13] RISC-V: Provide fmin'/fmax' RTL patterns https://gcc.gnu.org/pipermail/gcc-patches/2022-February/590006.html

Binutils/GDB

GNU Binutils 2.38 has been released https://sourceware.org/pipermail/binutils/2022-February/119721.html
[PATCH 0/5] RISC-V: Add Ratified Cache Management Operation ISA Extensions (with paren) https://sourceware.org/pipermail/binutils/2022-February/119708.html
GDB: [PATCH 00/12] A little TLC for the simulators (in particular CRIS) https://sourceware.org/pipermail/gdb-patches/2022-February/185868.html
GDB: [PATCH 0/5] Functions call history patches https://sourceware.org/pipermail/gdb-patches/2022-February/185814.html

GLIBC

[PATCH v1] x86: Fix bug in strncmp-evex and strncmp-avx2 [BZ #28895] https://sourceware.org/pipermail/libc-alpha/2022-February/136511.html
[PATCH v3 5/7] x86: Optimize strcmp-avx2.S https://sourceware.org/pipermail/libc-alpha/2022-February/136492.html
[PATCH v2] x86-64: Optimize bzero https://sourceware.org/pipermail/libc-alpha/2022-February/136390.html
[PATCH 00/12] Remove bcopy and bzero optimizations https://sourceware.org/pipermail/libc-alpha/2022-February/136377.html
Accuracy of Mathematical Functions https://sourceware.org/pipermail/libc-alpha/2022-February/136430.html

LLVM/Clang/LLDB/LLD

本节内容来自 LLVM Weekly 第 424 期， Alex Bradbury 大哥持续稳定输出。

宋教授上头条啦： MaskRay blogged about COMMON symbols.
A new paper on MLIR is up on arXiv - Composable and Modular Code Generation in MLIR: A Structured and Retargetable Approach to Tensor Compiler Construction.
Duncan P. N. Exon Smith posted an RFC on adding an LLVM content addressable storage library to facilitate experiments with using content-based caching in LLVM tools. The proposal has had most positive feedback. Chris Lattner made several suggestions. Duncan also provided some information on the direction Rust is going in.
Tobias Hieta proposed increasing the minimum Clang and GCC requirements for LLVM in order to allow C++17 usage. Mehdi Amini highlighted that raising the minimum version may cause challenges in distributing the compiler/library binaries, which should also be considered. Tobias followed up with a list of potential next steps.
Peter Smith is seeking feedback on an LLD deprecation policy.
River Riddle provided an update on removing the MLIR standard dialect, noting that it now only had 4 operations left.
LLVM 14.0.0-rc1 has been tagged.
Alex Rosenberg raised concerns about the Clang "pseudo parser" being committed without full consensus.
估计又要社区吵很久？ On behalf of the LLVM Foundation Board of Directors, Tom Stellard reported that the Board had received the comment summary regarding LLVM's code review process, but need more time to make a decision and will wait until at least the Discourse retrospective feedback collections is complete.
吵了很久了。 On behalf of the LLVM Foundation, Tanya Lattner is inviting feedback on the move to Discourse. The feedback is requested by March 7th, and the post lists questions to answer and points to consider in your response. Also on the topic of the Discourse migration, mailing list mode is now enabled again and James Y Knight noted there seems to be issues with dropped content in some imported emails.
EuroLLVM 2022 is expected to take place in person in the 2nd week of May in the UK. Volunteers are sought for the program committee.
Pavel Labath posted an RFC on adding support for a system-wide lldbinit.
Tom Stellard shared an RFC for adding new automation around creating issues for backporting bugfixes to release branches.
Slides and a recording from last week's Open MLIR meeting (about the MLIR-PyTACO bridge) are now available.
宋教授双杀！ Fangrui Song raised the prospect of removing support for 'standalone builds', noting they are frequently broken. Multiple respondents noted that standalone builds are useful for packaging purposes, but the question of who could take ownership of maintaining support remains open.
There have been several proposals in the last week regarding new working groups or meeting times for existing groups. An in-person Women in Compilers and Tools meetup is proposed for the week of the 7th March (the week of International Women's day). Participate in the poll if you're interested. Meanwhile, Volodymyr Turanskyy is establishing a regular LLVM Embedded Toolchains Working Group and sync-up and Jeff Heath and others at Intel are proposing a Clang C/C++ language working group. This group would focus on facilitating and accelerating standard C/C++ language development in Clang/LLVM.
David Chisnall initiated a discussion about whether it's time to start upstreaming CHERI support to LLVM.
恭喜！ The LoongArch backend started to land upstream. 42fd2bf, e53e6ec, 444c6d2, 33388ae, 6caee48, af3bc0d.
积跬步： Inline asm constraint support, ProcessorModel definitions, and a disassembler were added for the CSKY backend. a190fcd, 9ee96aa, ec642ce.
日综一卒： The Flang driver gained support for the -emit-mlir option. 69c3309.
日拱一卒： An optimised memmove implementation was added to LLVM's libc. 83f9b13.

QEMU (RISC-V)

[PATCH] target/riscv: Call probe_write() before atomic operations. https://lists.nongnu.org/archive/html/qemu-riscv/2022-02/msg00073.html
[PATCH v3] target/riscv: Enable Zicbo[m,z,p] instructions. https://lists.nongnu.org/archive/html/qemu-riscv/2022-02/msg00084.html
[PATCH v6 0/6] support subsets of Float-Point in Integer Registers extensions. https://lists.nongnu.org/archive/html/qemu-riscv/2022-02/msg00094.html

RISC-V in China

香山处理器回片， SPEC CPU 2006 结果出炉，很棒！
RV双周报：Intel加入RISC-V阵营，RV处理器IP市场高速增长(20220129-20220210)

RT-Thread 社区

RT-Thread创始人新年寄语: 开源如水、商业似船
【AI简报20220211期】硬核UP主自己造了一个激光雷达、详解AI加速器
RT-Thread v4.1.0 Beta 发布,更完善的 POSIX 支持（PSE51 以及其他常用的POSIX API 支持）、跨多编译器平台的支持、稳定精简的系统内核、CPP11支持（gcc、armclang 双平台支持）、64位架构支持，更多的原厂BSP（瑞萨、新唐、先楫、沁恒、小华半导体、东软载波...）

TVM / MLIR / AI Compilers

风平浪静

本周工具链岗位

往期社招及实习生招聘长期有效。

本周推荐阅读

本周推荐：《邓小平时代》

作者：傅高义

译者：冯克利

推荐人：小编1号

我一直回避深入的阅读中国的现代史，因为觉得按照中国传统，这很难得到客观的评价。但是毫无疑问，傅高义教授的这本700多页的大部头改变了我的看法。我推荐所有人都阅读一遍，购买纸质的图书。

书中印象最深的场景有很多，意外触动我到流泪的，是1970年代邓小平第一次出访国外，路过法国，早上吃牛角面包，喝咖啡，就像1920年代一样。回国的时候，他买了几百个牛角面包和奶酪，带回国，分给了周总理等当年一起在法国呆过的伙伴。

之后我吃了一周的牛角面包。