第三届中国 Rust 开发者大会 Learning by Contributing to Rust Compiler Yukang github.com/chenyukang Engineer @ Cryptape Leveling Up in Rust • 2011 ~ 2014 EDA startup C/C++ • 2014 ~ 2020 DJI Infra tools, code refactor, algorithms improvements Some PR stories • Rust cares about error messages • We are building a sufficiently empathetic compiler • It’s a trade-off Diagnostic is an art art Simple diagnostic is a good start Compiler is a teacher/friend [# 100502 Avoid infinite loop in function arguments checking] A trivial fix may require a lot of time ? Fix the bug of next_point

Escapes  Trim Whitespace Before Line Splicing  C++23 Standard Library  String Formatting Improvements  Standard Library Modules  std::flat_(multi)map / std::flat_(multi)set  std::mdspan  std::generator Escapes  Trim Whitespace Before Line Splicing  C++23 Standard Library  String Formatting Improvements  Standard Library Modules  std::flat_(multi)map / std::flat_(multi)set  std::mdspan  std::generator Escapes  Trim Whitespace Before Line Splicing  C++23 Standard Library  String Formatting Improvements  Standard Library Modules  std::flat_(multi)map / std::flat_(multi)set  std::mdspan  std::generator

participating in the creation of the C++ Standards 2. by investing in the Microsoft Visual C++ (MSVC) Compiler & Libraries 3. by simplifying acquisition in C++ via vcpkg 4. by improving the Visual Studio IDE your code (with the same compiler as today) 💡 MSVC 2015, 2017 and 2019 toolsets are available directly from Visual Studio 2022 Step #3: Compile your code with the latest compiler 💡 Binary compatibility previous C++ runtimes (VS 2019, VS 2017, VS 2015) Step #4: Compile your dependencies with the latest compiler 💡 Have peace of mind upgrading all your open-source libraries with vcpkg (https://vcpkg.io) Next:

MAKE_LANG_COMPILER_ID.html#variable:CMAKE_%3CLANG%3E_COMPILER_ID 也可以用生成器表达式判断编译器 https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_COMPILER_ID.html#variable:CMAKE_%3CLANG%3E_COMPILER_ID 生成器表达式也可以做复杂的逻辑判断 生成器表达式也可以做复杂的逻辑判断 CMake 还提供了一些简写变量： MSVC, CMAKE_COMPILER_IS_GNUCC CMAKE_CXX_COMPILER_ID 直接作为字符串变量 从命令行参数指定编译器 也可以通过环境变量 CXX 指定 CMAKE_GENERATOR 也可以了解一下 顺便一提，小彭老师使用的 vimrc 分享 github.com/archibate/vimrc

to precompiled header files (PCH)  Custom headers can also be made importable, but how to is compiler dependent “How C++20 Changes the Way We Write Code” -- Timur Doumler Friday, September 18 • 12:00Ranges11 integral, constructible, …  sortable, mergeable, permutable, …24 Concepts  Concepts help with compiler error messages  Easier to read template error messages: e.g.: void Foo(Incrementable auto t) value49 Spaceship Operator <=>  Common case:  auto X::operator<=>(const Y&) const = default;  Compiler generates all 6 comparison operators to compare X with Y (memberwise)  Advanced:  Non-defaulted

function returns in caller provided memory. This is often unexpected but occurs using the MSVC compiler for x86 with stdcall (callee cleanup) or cdecl (caller cleanup). For non-MSVC, data_t is always may not be prepared for a C++ exception – of any sort. The typical result is ... undefined. What compiler flags (clang) were used by the library? By the library consumer? -fsjlj-exceptions? -fignore-exceptions is meant – integer sizes, string encoding, etc. • Interop scenarios often aren’t using a C++ compiler to read the header, humans are. • Kate Gregory’s “What Do We Mean When We Say Nothing At All

behavior of this flag may change in future compiler releases. https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/ index.html#options-for-altering-compiler-linker-behavior-expt-relaxed- constexpr Using

that uses a large matrix multiply function. Using a combination of new ordering and the Intel MIC compiler directives, performance on the Intel Xeon Phi coprocessor was up to 36 X faster, and on the Intel

这个版本号是编译时指定的版本，不是运 行时检测到的版本。编译器默认就是最老 的 52 ，能兼容所有 GTX900 以上显卡。 https://docs.nvidia.com/cuda/cuda-compiler-driver-nvcc/index.html#extended-notation 针对不同的架构，使用不同的代码 通过 CMake 设置架构版本号 • 可以用 CMAKE_CUDA_ARCHITECTURES