The cg_clif project has made significant progress in compiling Rust to C, achieving a 95.9% pass rate on the Rust test suite. This compiler leverages Cranelift as a backend and utilizes a custom ABI for passing Rust data structures. Notably, it's now functional on more unusual platforms like wasm32-wasi and thumbv6m-none-eabi (for embedded ARM devices). While performance isn't a primary focus currently, basic functionality and compatibility are progressing rapidly, demonstrating the potential for compiling Rust to a portable C representation.
GCC 15 introduces several usability enhancements. Improved diagnostics offer more concise and helpful error messages, including location information within macros and clearer explanations for common mistakes. The new -fanalyzer option provides static analysis capabilities to detect potential issues like double-free errors and use-after-free vulnerabilities. Link-time optimization (LTO) is more robust with improved diagnostics, and the compiler can now generate more efficient code for specific targets like Arm and x86. Additionally, improved support for C++20 and C2x features simplifies development with modern language standards. Finally, built-in functions for common mathematical operations have been optimized, potentially improving performance without requiring code changes.
Hacker News users generally expressed appreciation for the continued usability improvements in GCC. Several commenters highlighted the value of the improved diagnostics, particularly the location information and suggestions, making debugging significantly easier. Some discussed the importance of such advancements for both novice and experienced programmers. One commenter noted the surprisingly rapid adoption of these improvements in Fedora's GCC packages. Others touched on broader topics like the challenges of maintaining large codebases and the benefits of static analysis tools. A few users shared personal anecdotes of wrestling with confusing GCC error messages in the past, emphasizing the positive impact of these changes.
C3 is a new programming language designed as a modern alternative to C. It aims to be safer and easier to use while maintaining C's performance and low-level control. Key features include optional memory safety through compile-time checks and garbage collection, improved syntax and error messages, and built-in modularity. The project is actively under development and includes a self-hosting compiler written in C3. The goal is to provide a practical language for systems programming and other performance-sensitive domains while mitigating common C pitfalls.
HN users discuss C3's goals and features, expressing both interest and skepticism. Several question the need for another C-like language, especially given the continued development of C and C++. Some appreciate the focus on safety and preventing common C errors, while others find the changes too drastic a departure from C's philosophy. There's debate about the practicality of automatic memory management in systems programming, and some concern over the runtime overhead it might introduce. The project's early stage is noted, and some express reservations about its long-term viability and community adoption. Others are more optimistic, praising the clear documentation and expressing interest in following its progress. The use of Python for the compiler is also a point of discussion.
This guide provides a curated list of compiler flags for GCC, Clang, and MSVC, designed to harden C and C++ code against security vulnerabilities. It focuses on options that enable various exploit mitigations, such as stack protectors, control-flow integrity (CFI), address space layout randomization (ASLR), and shadow stacks. The guide categorizes flags by their protective mechanisms, emphasizing practical usage with clear explanations and examples. It also highlights potential compatibility issues and performance impacts, aiming to help developers choose appropriate hardening options for their projects. By leveraging these compiler-based defenses, developers can significantly reduce the risk of successful exploits targeting their software.
Hacker News users generally praised the OpenSSF's compiler hardening guide for C and C++. Several commenters highlighted the importance of such guides in improving overall software security, particularly given the prevalence of C and C++ in critical systems. Some discussed the practicality of implementing all the recommendations, noting potential performance trade-offs and the need for careful consideration depending on the specific project. A few users also mentioned the guide's usefulness for learning more about compiler options and their security implications, even for experienced developers. Some wished for similar guides for other languages, and others offered additional suggestions for hardening, like using static and dynamic analysis tools. One commenter pointed out the difference between control-flow hijacking mitigations and memory safety, emphasizing the limitations of the former.
This paper explores practical strategies for hardening C and C++ software against memory safety vulnerabilities without relying on memory-safe languages or rewriting entire codebases. It focuses on compiler-based mitigations, leveraging techniques like Control-Flow Integrity (CFI) and Shadow Stacks, and highlights how these can be effectively deployed even in complex, legacy projects with limited resources. The paper emphasizes the importance of a layered security approach, combining static and dynamic analysis tools with runtime protections to minimize attack surfaces and contain the impact of potential exploits. It argues that while a complete shift to memory-safe languages is ideal, these mitigation techniques offer valuable interim protection and represent a pragmatic approach for enhancing the security of existing C/C++ software in the real world.
Hacker News users discussed the practicality and effectiveness of the proposed "TypeArmor" system for securing C/C++ code. Some expressed skepticism about its performance overhead and the complexity of retrofitting it onto existing projects, questioning its viability compared to rewriting in memory-safe languages like Rust. Others were more optimistic, viewing TypeArmor as a potentially valuable tool for hardening legacy codebases where rewriting is not feasible. The discussion touched upon the trade-offs between security and performance, the challenges of integrating such a system into real-world projects, and the overall feasibility of achieving robust memory safety in C/C++ without fundamental language changes. Several commenters also pointed out limitations of TypeArmor, such as its inability to handle certain complex pointer manipulations and the potential for vulnerabilities in the TypeArmor system itself. The general consensus seemed to be cautious interest, acknowledging the potential benefits while remaining pragmatic about the inherent difficulties of securing C/C++.
This blog post explains why the author chose C to build their personal website. Motivated by a desire for a fun, challenging project and greater control over performance and resource usage, they opted against higher-level frameworks. While acknowledging C's complexity and development time, the author highlights the benefits of minimal dependencies, small executable size, and the learning experience gained. Ultimately, the decision was driven by personal preference and the satisfaction derived from crafting a website from scratch using a language they enjoy.
Hacker News users generally praised the author's technical skills and the site's performance, with several expressing admiration for the clean code and minimalist approach. Some questioned the practicality and maintainability of using C for a website, particularly regarding long-term development and potential security risks. Others discussed the benefits of learning C and low-level programming, while some debated the performance advantages compared to other languages and frameworks. A few users shared their own experiences with similar projects and alternative approaches to achieving high performance. A significant point of discussion was the lack of server-side rendering, which some felt hindered the site's SEO.
LVGL is a free and open-source graphics library providing everything you need to create embedded GUIs with easy-to-use graphical elements, beautiful visual effects, and a low memory footprint. It's designed to be platform-agnostic, supporting a wide range of input devices and hardware from microcontrollers to powerful embedded systems like the Raspberry Pi. Key features include scalable vector graphics, animations, anti-aliasing, Unicode support, and a flexible style system for customizing the look and feel of the interface. With its rich set of widgets, themes, and an active community, LVGL simplifies the development process of visually appealing and responsive embedded GUIs.
HN commenters generally praise LVGL's ease of use, beautiful output, and good documentation. Several note its suitability for microcontrollers, especially with limited resources. Some express concern about its memory footprint, even with optimizations, and question its performance compared to other GUI libraries. A few users share their positive experiences integrating LVGL into their projects, highlighting its straightforward integration and active community. Others discuss the licensing (MIT) and its suitability for commercial products. The lack of a GPU dependency is mentioned as both a positive and negative, offering flexibility but potentially impacting performance for complex graphics. Finally, some comments compare LVGL to other embedded GUI libraries, with varying opinions on its relative strengths and weaknesses.
This blog post details how to create a statically linked Go executable that utilizes C code, overcoming the challenges typically associated with CGO and external dependencies. The author leverages Zig as a build system and cross-compiler, using its ability to compile C code and link it directly into a Go-compatible archive. This approach eliminates the need for a system C toolchain on the target machine during deployment, producing a truly self-contained binary. The post provides a practical example, guiding the reader through the necessary Zig build script configuration and explaining the underlying principles. This allows for simplified deployment, particularly useful for environments like scratch Docker containers, and offers a more robust and reproducible build process.
Hacker News users discuss the clever use of Zig as a build tool to statically link C dependencies for Go programs, effectively bypassing the complexities of cgo and resulting in self-contained binaries. Several commenters praise the approach for its elegance and practicality, particularly for cross-compilation scenarios. Some express concern about the potential fragility of relying on undocumented Go internals, while others highlight the ongoing efforts within the Go community to address static linking natively. A few users suggest alternative solutions like using Docker for consistent build environments or exploring fully statically-linked C libraries. The overall sentiment is positive, with many appreciating the ingenuity and potential of this Zig-based workaround.
The symbol 'c' for the speed of light likely comes from the Latin word "celeritas," meaning swiftness or speed. While sometimes attributed to Einstein, he used 'V' in his early work. 'c' became the standard symbol later, possibly arising from the study of electromagnetic waves where 'c' represented a constant in Maxwell's equations. Its precise origin remains somewhat uncertain, but the connection to "celeritas" and the established use of 'c' for wave propagation constants are the most probable explanations.
The Hacker News comments discuss the origin of "c" for the speed of light, with most agreeing it likely comes from "constant" or the Latin "celeritas" (swiftness). Some debate whether Maxwell originally used "V" or another symbol, and whether "c" became standard before Einstein. A compelling comment highlights the difference between defining c as the speed of light versus recognizing it as a fundamental constant relating space and time, with implications beyond just light. Another interesting point raised is that "c" represents the speed of causality, the fastest rate at which information can propagate, regardless of the medium. There's also brief discussion of the historical context of measuring the speed of light and the development of electromagnetic theory.
The Ncurses library provides an API for creating text-based user interfaces in a terminal-independent manner. It handles screen painting, input, and window management, abstracting away low-level details like terminal capabilities. Ncurses builds upon the older Curses library, offering enhancements and broader compatibility. Key features include window creation and manipulation, formatted output with color and attributes, handling keyboard and mouse input, and supporting various terminal types. The library simplifies tasks like creating menus, dialog boxes, and other interactive elements commonly found in text-based applications. By using Ncurses, developers can write portable code that works across different operating systems and terminal emulators without modification.
Hacker News users discussing the ncurses intro document generally praised it as a good resource, especially for beginners. Some appreciated the historical context provided, while others highlighted the clarity and practicality of the tutorial. One commenter mentioned using it to learn ncurses for a project, showcasing its real-world applicability. Several comments pointed out modern alternatives like FTXUI (C++) and blessed-contrib (JS), acknowledging ncurses' age but also its continued relevance and wide usage in existing tools. A few users discussed the benefits of text-based UIs, citing speed, remote accessibility, and lower resource requirements.
This GitHub repository preserves incredibly early versions of Dennis Ritchie's Portable C Compiler, including pre-1.0 snapshots dating back to the late 1970s. These versions offer a fascinating glimpse into the evolution of C, showcasing its transition from a research language to the widespread programming powerhouse it became. The repository aims to archive these historically significant artifacts, making them available for study and exploration by those interested in the origins and development of C. It includes various versions for different architectures, providing valuable insights into early compiler design and the challenges of portability in the nascent days of Unix.
Hacker News users discussed the historical significance of the rediscovered C compiler source code, noting its use of PDP-11 assembly and the challenges of porting it to modern systems due to its tight coupling with the original hardware. Several commenters expressed interest in its educational value for understanding early compiler design and the evolution of C. Some debated the compiler's true "firstness," acknowledging earlier, possibly lost, versions, while others focused on the practical difficulties of building and running such old code. A few users shared personal anecdotes about their experiences with early C compilers and PDP-11 machines, adding a personal touch to the historical discussion. The overall sentiment was one of appreciation for the preservation and sharing of this piece of computing history.
The author details the process of creating a ZX Spectrum game from scratch, starting with C code for core game logic. This C code was then manually translated into Z80 assembly, a challenging process requiring careful consideration of memory management and hardware limitations. After the assembly code was complete, they created a loading screen and integrated everything into a working .tap file, the standard format for Spectrum games. This involved understanding the intricacies of the Spectrum's tape loading system and manipulating audio frequencies to encode the game data for reliable loading on original hardware. The result was a playable game demonstrating a complete pipeline from high-level language to a functional retro game program.
Hacker News users discuss the impressive feat of converting C code to Z80 assembly and then to a working ZX Spectrum tape. Several commenters praise the author's clear explanation of the process and the clever tricks used to optimize for the Z80's limited resources. Some share nostalgic memories of working with the ZX Spectrum and Z80 assembly, while others delve into technical details like memory management and the challenges of cross-development. A few highlight the educational value of the project, showing the direct connection between high-level languages and the underlying hardware. One compelling comment thread discusses the efficiency of the generated Z80 code compared to hand-written assembly, with differing opinions on whether the compiler's output could be further improved. Another interesting exchange revolves around the practical applications of such a technique today, ranging from embedded systems to retro game development.
The blog post "Zlib-rs is faster than C" demonstrates how the Rust zlib-rs crate, a wrapper around the C zlib library, can achieve significantly faster decompression speeds than directly using the C library. This surprising performance gain comes from leveraging Rust's zero-cost abstractions and more efficient memory management. Specifically, zlib-rs uses a custom allocator optimized for the specific memory usage patterns of zlib, minimizing allocations and deallocations, which constitute a significant performance bottleneck in the C version. This specialized allocator, combined with Rust's ownership system, leads to measurable speed improvements in various decompression scenarios. The post concludes that careful Rust wrappers can outperform even highly optimized C code by intelligently managing resources and eliminating overhead.
Hacker News commenters discuss potential reasons for the Rust zlib implementation's speed advantage, including compiler optimizations, different default settings (particularly compression level), and potential benchmark inaccuracies. Some express skepticism about the blog post's claims, emphasizing the maturity and optimization of the C zlib implementation. Others suggest potential areas of improvement in the benchmark itself, like exploring different compression levels and datasets. A few commenters also highlight the impressive nature of Rust's performance relative to C, even if the benchmark isn't perfect, and commend the blog post author for their work. Several commenters point to the use of miniz, a single-file C implementation of zlib, suggesting this may not be a truly representative comparison to zlib itself. Finally, some users provided updates with their own benchmark results attempting to reconcile the discrepancies.
By exploiting a flaw in OpenAI's code interpreter, a user managed to bypass restrictions and execute C and JavaScript code directly. This was achieved by crafting prompts that tricked the system into interpreting uploaded files as executable code, rather than just data. Essentially, the user disguised the code within specially formatted files, effectively hiding it from OpenAI's initial safety checks. This demonstrated a vulnerability in the interpreter's handling of uploaded files and its ability to distinguish between data and executable code. While the user demonstrated this with C and Javascript, the method theoretically could be extended to other languages, raising concerns about the security and control mechanisms within such AI coding environments.
HN commenters were generally impressed with the hack, calling it "clever" and "ingenious." Some expressed concern about the security implications of being able to execute arbitrary code within OpenAI's models, particularly as models become more powerful. Others discussed the potential for this technique to be used for beneficial purposes, such as running specialized calculations or interacting with external APIs. There was also debate about whether this constituted "true" code execution or was simply manipulating the model's existing capabilities. Several users highlighted the ongoing cat-and-mouse game between prompt injection attacks and defenses, suggesting this was a significant development in that ongoing battle. A few pointed out the limitations, noting it's not truly compiling or running code but rather coaxing the model into simulating the desired behavior.
Driven by a desire for simplicity and performance in a personal project involving embedded systems and game development, the author rediscovered their passion for C. After years of working with higher-level languages, they found the direct control and predictable behavior of C refreshing and efficient. This shift allowed them to focus on core programming principles and optimize their code for resource-constrained environments, ultimately leading to a more satisfying and performant outcome than they felt was achievable with more complex tools. They argue that while modern languages offer conveniences, C's close-to-the-metal nature provides a unique learning experience and performance advantage, particularly for certain applications.
HN commenters largely agree with the author's points about C's advantages, particularly its predictability and control over performance. Several praised the feeling of being "close to the metal" and the satisfaction of understanding exactly how the code interacts with the hardware. Some offered additional benefits of C, such as easier debugging due to its simpler execution model and its usefulness in constrained environments. A few commenters cautioned against romanticizing C, pointing out its drawbacks like manual memory management and the potential for security vulnerabilities. One commenter suggested Zig as a modern alternative that addresses some of C's shortcomings while maintaining its performance benefits. The discussion also touched on the enduring relevance of C, particularly in foundational systems and performance-critical applications.
Krep is a fast string search utility written in C, designed for performance-sensitive tasks. It utilizes SIMD instructions and optimized algorithms to achieve speeds significantly faster than grep and other similar tools, especially when searching large files or codebases. Krep supports regular expressions via PCRE2, various output formats including JSON and CSV, and features like ignoring binary files and following symbolic links. The project is open-source and aims to provide a robust and efficient alternative for command-line text searching.
HN users generally praised Krep for its speed and clean implementation. Several commenters compared it favorably to other popular search tools like ripgrep and grep, with some noting its superior performance in specific scenarios. One user suggested incorporating SIMD instructions for potential further speed improvements. Discussion also touched on the nuances of benchmarking and the importance of real-world test cases, with one commenter sharing their own benchmark results where krep excelled. A few users inquired about specific features, like support for PCRE (Perl Compatible Regular Expressions) or Unicode character classes. Overall, the reception was positive, acknowledging krep as a promising tool for efficient string searching.
Vtm is a terminal-based desktop environment built with Python and inspired by tiling window managers. It aims to provide a lightweight and keyboard-driven workflow, allowing users to manage multiple terminal windows within a single terminal instance. Vtm utilizes a tree-like structure for window organization, enabling split layouts and tabbed interfaces. Its configuration is handled through a simple Python file, offering customization options for keybindings, colors, and startup applications. Ultimately, Vtm strives to offer a minimalist and efficient terminal experience for users who prefer a text-based environment.
Hacker News users discuss vtm, a text-based desktop environment, focusing on its potential niche use cases. Some commenters see value in its minimal resource usage for embedded systems or as a fallback interface. Others appreciate the accessibility benefits for visually impaired users or those who prefer keyboard-driven workflows. Several express interest in trying vtm out of curiosity or for specific tasks like remote server administration. A few highlight the project's novelty and the nostalgic appeal of text-based interfaces. Some skepticism is voiced regarding its practicality compared to modern graphical DEs, but the overall sentiment is positive, with many praising the developer's effort and acknowledging the potential value of such a project. A discussion arises about the use of terminology, clarifying the difference between a window manager and a desktop environment. The lightweight nature of vtm and its integration with notcurses are also highlighted.
Ggwave is a small, cross-platform C library designed for transmitting data over sound using short, data-encoded tones. It focuses on simplicity and efficiency, supporting various payload formats including text, binary data, and URLs. The library provides functionalities for both sending and receiving, using a frequency-shift keying (FSK) modulation scheme. It features adjustable parameters like volume, data rate, and error correction level, allowing optimization for different environments and use-cases. Ggwave is designed to be easily integrated into other projects due to its small size and minimal dependencies, making it suitable for applications like device pairing, configuration sharing, or proximity-based data transfer.
HN commenters generally praise ggwave's simplicity and small size, finding it impressive and potentially useful for various applications like IoT device setup or offline data transfer. Some appreciated the clear documentation and examples. Several users discuss potential use cases, including sneaker authentication, sharing WiFi credentials, and transferring small files between devices. Concerns were raised about real-world robustness and susceptibility to noise, with some suggesting potential improvements like forward error correction. Comparisons were made to similar technologies, mentioning limitations of existing sonic data transfer methods. A few comments delve into technical aspects, like frequency selection and modulation techniques, with one commenter highlighting the choice of Goertzel algorithm for decoding.
OpenJKDF2 is a cross-platform, open-source reimplementation of the Jedi Knight II: Jedi Outcast and Jedi Academy game engine written in C. It aims to be a clean and modern engine while maintaining compatibility with the original games' content, supporting both single-player and multiplayer modes. The project prioritizes features like improved rendering, physics, and networking, allowing for modifications and enhancements beyond what was possible with the original engine. It's designed to be portable and has been tested on Windows, macOS, and Linux.
Hacker News users discuss OpenJKDF2's potential benefits, including cross-platform compatibility and potential performance improvements over the original Jedi Knight II: Jedi Outcast game engine. Some express excitement about potential modding opportunities and the project's clean codebase, making it easier to understand and contribute to. Others question the practical benefits, wondering if the performance gains are substantial enough to warrant a full reimplementation. The use of CMake is praised, while concerns are raised about the licensing implications of incorporating assets from the original game. One commenter points out potential issues with online multiplayer due to timing differences, which are hard to replicate perfectly.
The author seeks a C-like language with modern features like generics, modules, and memory safety, while maintaining C's performance and close-to-the-metal nature. They desire a language suitable for systems programming, potentially as a replacement for C in performance-critical applications, but with the added benefits of contemporary language design. They are exploring if such a language already exists or whether retrofitting C would be a more viable approach. Essentially, they want the power and control of C without its inherent pitfalls and limitations.
The Hacker News comments discuss the practicality and potential benefits of a "retrofitted" C dialect, primarily focusing on memory safety. Some suggest exploring existing options like Zig, Rust, or Odin, which already address many of C's shortcomings. Others express skepticism about the feasibility of such a project, citing the complexity of C's ecosystem and the difficulty of maintaining compatibility while introducing significant changes. A few commenters propose specific improvements, such as optional garbage collection or stricter type checking, but acknowledge the challenges in implementation and adoption. There's a general agreement that memory safety is crucial, but opinions diverge on whether a new dialect or focusing on tooling and better practices within existing C is the best approach. Some also discuss the potential benefits for embedded systems, where C remains dominant.
After a year of using the uv HTTP server for production, the author found it performant and easy to integrate with existing C code, praising its small binary size, minimal dependencies, and speed. However, the project is relatively immature, leading to occasional bugs and missing features compared to more established servers like Nginx or Caddy. While documentation has improved, it still lacks depth. The author concludes that uv is a solid choice for projects prioritizing performance and tight C integration, especially when resources are constrained. However, those needing a feature-rich and stable solution might be better served by a more mature alternative. Ultimately, the decision to migrate depends on individual project needs and risk tolerance.
Hacker News users generally reacted positively to the author's experience with the uv terminal multiplexer. Several commenters echoed the author's praise for uv's speed and responsiveness, particularly compared to alternatives like tmux. Some highlighted specific features they appreciated, such as the intuitive copy-paste functionality and the project's active development. A few users mentioned minor issues or missing features, like lack of support for nested sessions or certain keybindings, but these were generally framed as minor inconveniences rather than major drawbacks. Overall, the sentiment leaned towards recommending uv as a strong contender in the terminal multiplexer space, especially for those prioritizing performance.
A recent Clang optimization introduced in version 17 regressed performance when compiling code containing large switch statements within inlined functions. This regression manifested as significantly increased compile times, sometimes by orders of magnitude, and occasionally resulted in internal compiler errors. The issue stems from Clang's attempt to optimize switch lowering by transforming it into a series of conditional moves based on jump tables. This optimization, while beneficial in some cases, interacts poorly with inlining, exploding the complexity of the generated intermediate representation (IR) when a function with a large switch is inlined multiple times. This ultimately overwhelms the compiler's later optimization passes. A workaround involves disabling the problematic optimization via a compiler flag (-mllvm -switch-to-lookup-table-threshold=0) until a proper fix is implemented in a future Clang release.
The Hacker News comments discuss a performance regression in Clang involving large switch statements and inlining. Several commenters confirm experiencing similar issues, particularly when compiling large codebases. Some suggest the regression might be related to changes in the inlining heuristics or the way Clang handles jump tables. One commenter points out that using a constexpr hash table for large switches can be a faster alternative. Another suggests profiling and selective inlining as a workaround. The lack of clear identification of the root cause and the potential impact on compile times and performance are highlighted as concerning. Some users express frustration with the frequency of such regressions in Clang.
cute_headers is a curated collection of single-header C/C++ libraries, specifically geared towards game development. These libraries are designed to be easily integrated, requiring no external dependencies or build systems. They cover a range of functionalities often needed in games, including linear algebra, collision detection, graphics, input handling, and more. The project aims to provide a convenient and lightweight way to access commonly used tools without the overhead of complex library management. This makes them particularly suitable for small projects, rapid prototyping, or learning purposes.
Hacker News users generally praised the simplicity and utility of Randy Gaul's single-file libraries. Several commenters highlighted the educational value of the code, particularly for understanding fundamental game development concepts and data structures. Some discussed the trade-offs of using such minimal libraries versus larger, more feature-rich alternatives, acknowledging the benefits of these smaller libraries for learning and small projects while recognizing potential limitations for complex endeavors. A few commenters also mentioned specific libraries they found particularly interesting or useful, including the string library and the JSON parser. There was a short thread discussing licensing, ultimately confirming that the MIT license allows for commercial use.
The author details their process of creating a WebAssembly (Wasm) virtual machine (VM) written entirely in C. Driven by a desire for a lightweight, embeddable Wasm runtime for resource-constrained environments, they built the VM from scratch, implementing core features like the stack-based execution model, linear memory, and basic WebAssembly System Interface (WASI) support. The project focused on simplicity and understandability over performance, serving primarily as a learning exercise and a platform for experimentation with Wasm. The post walks through key aspects of the VM's design and implementation, including parsing the Wasm binary format, handling function calls, and managing memory. It also highlights the challenges faced and lessons learned during the development process.
Hacker News users generally praised the author's clear writing style and the educational value of the post. Several commenters discussed the project's performance, noting that it's not optimized for speed and suggesting potential improvements like just-in-time compilation. Some shared their own experiences with WASM interpreters and related projects, including comparisons to other implementations and alternative approaches like using a stack machine. Others appreciated the detailed explanation of the parsing and execution process, finding it helpful for understanding WASM internals. A few users pointed out minor corrections or areas for potential enhancement in the code, demonstrating active engagement with the technical details.
The blog post argues for a standardized, cross-platform OS API specifically designed for timers. Existing timer mechanisms, like POSIX's timerfd and Windows' CreateWaitableTimer, while useful, differ significantly across operating systems, complicating cross-platform development. The author proposes a new API with a consistent interface that abstracts away these platform-specific details. This ideal API would allow developers to create, arm, and disarm timers, specifying absolute or relative deadlines with optional periodic behavior, all while handling potential issues like early wake-ups gracefully. This would simplify codebases and improve portability for applications relying on precise timing across different operating systems.
The Hacker News comments discuss the complexities of cross-platform timer APIs, largely agreeing with the article's premise. Several commenters highlight the difficulties introduced by different operating systems' power management features, impacting timer accuracy and reliability. Specific challenges like signal coalescing and the lack of a unified interface for monotonic timers are mentioned. Some propose workarounds like busy-waiting for short durations or using platform-specific code for optimal performance. The need for a standardized API is reiterated, with suggestions for what such an API should offer, including considerations for power efficiency and different timer resolutions. One commenter points to the challenges of abstracting away hardware differences completely, suggesting the ideal solution may involve a combination of OS-level improvements and application-specific strategies.
Uscope is a new, from-scratch debugger for Linux written in C and Python. It aims to be a modern, user-friendly alternative to GDB, boasting a simpler, more intuitive command language and interface. Key features include reverse debugging capabilities, a TUI interface with mouse support, and integration with Python scripting for extended functionality. The project is currently under active development and welcomes contributions.
Hacker News users generally expressed interest in Uscope, praising its clean UI and the ambition of building a debugger from scratch. Several commenters questioned the practical need for a new debugger given existing robust options like GDB, LLDB, and Delve, wondering about Uscope's potential advantages. Some discussed the challenges of debugger development, highlighting the complexities of DWARF parsing and platform compatibility. A few users suggested integrations with other tools, like REPLs, and requested features like remote debugging. The novelty of a fresh approach to debugging generated curiosity, but skepticism regarding long-term viability and differentiation also emerged. Some expressed concerns about feature parity with existing debuggers and the sustainability of the project.
The blog post showcases an incredibly compact WebAssembly compiler written in just a single tweet's worth of JavaScript code. This compiler takes a simplified subset of C code as input and directly outputs the corresponding WebAssembly binary format. It leverages JavaScript's ability to create typed arrays representing the binary structure of a .wasm file. While extremely limited in functionality (only supporting basic integer arithmetic and a handful of operations), it demonstrates the core principles of converting higher-level code to WebAssembly, offering a concise and educational example of how a compiler operates at its most fundamental level. The author emphasizes this isn't a practical compiler, but rather a fun exploration of code golfing and a digestible introduction to WebAssembly concepts.
Hacker News users generally expressed appreciation for the conciseness and elegance of the WebAssembly compiler presented in the tweet. Several commenters pointed out that while impressive, the compiler is limited and handles only a small subset of WebAssembly. Some discussed the potential educational value of such a minimal example, while others debated the practicality and performance implications. A few users delved into technical details, analyzing the specific instructions and optimizations used. The overall sentiment leaned towards admiration for the technical achievement, tempered with an understanding of its inherent limitations.
The blog post argues that C's insistence on abstracting away hardware details makes it poorly suited for effectively leveraging SIMD instructions. While extensions like intrinsics exist, they're cumbersome, non-portable, and break C's abstraction model. The author contends that higher-level languages, potentially with compiler support for automatic vectorization, or even assembly language for critical sections, would be more appropriate for SIMD programming due to the inherent need for data layout awareness and explicit control over vector operations. Essentially, C's strengths become weaknesses when dealing with SIMD, hindering performance and programmer productivity.
Hacker News users discussed the challenges of using SIMD effectively in C. Several commenters agreed with the author's point about the difficulty of expressing SIMD operations elegantly in C and how it often leads to unmaintainable code. Some suggested alternative approaches, like using higher-level languages or libraries that provide better abstractions, such as ISPC. Others pointed out the importance of compiler optimizations and using intrinsics effectively to achieve optimal performance. One compelling comment highlighted that the issue isn't inherent to C itself, but rather the lack of suitable standard library support, suggesting that future additions to the standard library could mitigate these problems. Another commenter offered a counterpoint, arguing that C's low-level nature is exactly why it's suitable for SIMD, giving programmers fine-grained control over hardware resources.
The blog post showcases efficient implementations of hash tables and dynamic arrays in C, prioritizing speed and simplicity over features. The hash table uses open addressing with linear probing and a power-of-two size, offering fast lookups and insertions. Resizing is handled by allocating a larger table and rehashing all elements, a process triggered when the table reaches a certain load factor. The dynamic array, built atop realloc, doubles in capacity when full, ensuring amortized constant-time appends while minimizing wasted space. Both examples emphasize practical performance over complex optimizations, providing clear and concise code suitable for embedding in performance-sensitive applications.
Hacker News users discuss the practicality and efficiency of Chris Wellons' C implementations of hash tables and dynamic arrays. Several commenters praise the clear and concise code, finding it a valuable learning resource. Some debate the choice of open addressing over separate chaining for the hash table, with proponents of open addressing citing better cache locality and less memory overhead. Others highlight the importance of proper hash functions and the potential performance degradation with high load factors in open addressing. A few users suggest alternative approaches, such as using C++ containers or optimizing for specific use cases, while acknowledging the educational value of Wellons' straightforward C examples. The discussion also touches on the trade-offs of manual memory management and the challenges of achieving both simplicity and performance.
This proposal introduces an effect system to C2x, aiming to enhance code modularity, optimization, and correctness by explicitly declaring and checking the side effects of functions. It defines a set of effect keywords, like reads and writes, to annotate function parameters and return values, indicating how they are accessed. These annotations are part of the function's type and are checked by the compiler, ensuring that declared effects match the function's actual behavior. The proposal also includes a mechanism for polymorphism over effects, enabling more flexible code reuse and separate compilation without sacrificing effect safety. This mechanism allows for abstracting over effects, so that functions can be written generically to operate on data structures with varying levels of mutability.
The Hacker News comments on the C2y effect system proposal express a mix of skepticism and cautious interest. Several commenters question the practicality and performance implications of implementing such a system in C, citing the language's existing complexity and the potential for significant overhead. Concerns are raised about the learning curve for developers and the possibility of introducing subtle bugs. Some find the proposal intriguing from a research perspective but doubt its widespread adoption. A few express interest in exploring the potential benefits of improved code analysis and error detection, particularly for concurrency and memory management, though acknowledge the challenges involved. Overall, the consensus leans towards viewing the proposal as an interesting academic exercise with limited real-world applicability in its current form.
Summary of Comments ( 164 )
https://news.ycombinator.com/item?id=43661329
Hacker News users discussed the impressive 95.9% test pass rate of the Rust-to-C compiler, particularly its ability to target unusual platforms like the Sega Saturn and Sony PlayStation. Some expressed skepticism about the practical applications, questioning the performance implications and debugging challenges of such a complex transpilation process. Others highlighted the potential benefits for code reuse and portability, enabling Rust code to run on legacy or resource-constrained systems. The project's novelty and ambition were generally praised, with several commenters expressing interest in the developer's approach and future developments. Some also debated the suitability of "compiler" versus "transpiler" to describe the project. There was also discussion around specific technical aspects, like memory management and the handling of Rust's borrow checker within the C output.
The Hacker News post titled "Rust to C compiler – 95.9% test pass rate, odd platforms" sparked a discussion with several interesting comments. Many commenters focused on the complexities and nuances of compiling Rust to C, particularly given Rust's unique memory management features.
One commenter highlighted the challenges inherent in translating Rust's borrow checker and ownership model into C, which lacks these built-in mechanisms. They questioned how the compiler handled these crucial aspects of Rust, expressing skepticism about achieving true compatibility without significant runtime overhead or limitations. This comment resonated with others who also expressed concern about the potential performance implications and the difficulty of replicating Rust's safety guarantees in C.
Another commenter pointed out the inherent difficulty in targeting "odd platforms," as mentioned in the title. They elaborated on the potential issues with varying C standard library implementations and the complexities of ensuring compatibility across diverse architectures and operating systems. This prompted a discussion about the trade-offs between portability and performance when attempting such a compilation process.
Several comments also touched on the potential use cases of such a compiler. Some suggested it could be valuable for embedded systems or environments where Rust isn't directly supported. Others questioned the practicality, arguing that if the target platform supports a C compiler, it might also be feasible to support a Rust compiler directly, potentially negating the need for a transpilation step.
The discussion also explored alternative approaches, such as compiling Rust to LLVM bitcode and then using LLVM to generate C code. This was presented as a potentially more robust approach that could leverage LLVM's optimizations and platform support.
Finally, some comments expressed interest in the specific platforms targeted by the project and requested more details about the remaining 4.1% of failing tests. They were curious about the nature of these failures and whether they represented fundamental limitations or solvable issues. Overall, the comments reflected a mixture of curiosity, skepticism, and cautious optimism about the potential of a Rust-to-C compiler.