Bun Crash: Segmentation Fault On MacOS With Vite

by Alex Johnson 49 views

Understanding the Segmentation Fault in Bun

Segmentation faults are a notoriously frustrating problem in software development. They represent a critical error where a program tries to access memory it's not allowed to. This often leads to the application crashing abruptly. In the context of the user's issue, the error occurs specifically within the Bun runtime environment when attempting to build a GUI container using vite. The user is using the oven/bun Docker container on an M3 Pro Macbook Pro running MacOS Tahoe 26.1 and OrbStack as the Docker provider. The crash is triggered by the command bunx --bun vite build, and it's consistently reproducible across various Bun versions, specifically within the 1.3.x and 1.2.x ranges. This suggests a deeper problem, possibly stemming from a combination of the user's system configuration, specific dependencies, or interactions between Bun and the vite build process. The provided stack trace points to JSC::CodeBlock::finishCreation in HashTable.h, which is a WebKit file, further implying a potential issue related to JavaScriptCore (JSC), the JavaScript engine used by Bun. It is important to note that the issue is consistent with using the latest version of dependencies. The user highlights the issue is only with the GUI container build and not the API container build that also uses Bun, indicating a dependency or build configuration difference could be a contributing factor. The error "Illegal instruction" suggests the CPU may not support the instruction set being used, which could be related to the specific build of Bun or how it's interacting with the host system. Finding the root cause requires diving deeper into the interplay between Bun, the user's system, and the project's dependencies, along with an understanding of memory management and low-level system interactions. The user's description and the provided details offer a good starting point for investigation.

Steps to Reproduce the Crash

To effectively tackle this segmentation fault in Bun, knowing how to replicate it is key. The user has thoughtfully laid out the precise steps needed to reproduce the crash. Here’s a breakdown of how the error can be triggered:

  1. Environment Setup: Start with the official oven/bun Docker container. The user's system involves an M3 Pro Macbook Pro with MacOS Tahoe 26.1 and uses OrbStack for Docker. This sets the stage with the right hardware and virtualization environment. Make sure that all the Docker images, containers and other tools are in the latest versions to avoid problems.
  2. Command Execution: The crash happens when the user runs bunx --bun vite build. This command initiates the build process of a GUI container using Vite, a frontend build tool. This step is the key to triggering the fault. The --bun flag specifies the Bun runtime.
  3. Dependency Consideration: The issue happens with a specific set of dependencies, which include packages such as @vitejs/plugin-vue, vue, and others listed in the user's package.json. These dependencies, along with their configurations within the vite.config.js file, can have a role in the crash.
  4. Version Testing: The user's testing across different Bun versions (1.3.x and 1.2.x ranges) confirms that the problem isn't isolated to a single Bun version. It highlights an underlying compatibility problem or a widespread issue.
  5. Build Process: The build process, which involves various steps handled by Vite, is the critical area where the crash happens. This involves compiling and optimizing the code, handling assets, and performing other tasks specific to the project's structure.
  6. Context: The user's proprietary application means that the exact source code is unavailable, making it more complicated. However, the available details still point to the nature of the issue.

By following these steps, anyone can try to reproduce the crash. It is important to pay close attention to the specific versions of Bun, dependencies, and build configurations, as even slight differences can change the outcome. Creating a test environment that matches the user's environment will help get closer to the cause of the segmentation fault.

Analyzing the Error Logs

Analyzing the error logs is crucial for diagnosing the segmentation fault. The user provides valuable log output, giving clues about the root of the problem. Here’s a detailed look at the relevant log details:

  1. Initial Warning: The log begins with a warning: oh no: multiple threads are crashing. This indicates a significant problem as multiple threads crashing simultaneously shows a more severe issue than a single-thread failure. It suggests a synchronization error or shared resource issue. This is a crucial aspect of the issue.
  2. Segmentation Fault: The core of the problem is highlighted by the panic(main thread): Segmentation fault at address 0x7FFFB28470E0. This confirms the segmentation fault, meaning the program tried to access a memory location it shouldn't. The memory address can provide information about what area is causing problems, though it requires further analysis.
  3. Bun.Report: The log output contains a link to bun.report. This can be a very useful resource since it provides details about the build, helping to understand the error better. It is important to share this file, as suggested in the prompts.
  4. Error Message: The error includes the message: error: script "build" was terminated by signal SIGILL (Illegal instruction). This is a critical piece of information. SIGILL indicates an illegal instruction error, usually due to the CPU encountering an instruction it does not support. It suggests a potential compatibility issue between the Bun version and the user's M3 Pro Macbook Pro. It could also mean the generated code uses instructions unsupported by the CPU.
  5. Stack Trace: The bun.report link also includes a stack trace. The stack trace starts with JSC::CodeBlock::finishCreation. This shows the specific function that failed. The function name means the failure occurs while creating code blocks, related to the JavaScript engine (JSC). It is important to study the stack trace to know how the program got to the point where the error happened.

Examining the error logs, specifically the SIGILL error and the stack trace, offers valuable insights. The segmentation fault, combined with illegal instructions, suggests a CPU-related incompatibility or low-level memory error. To solve this, consider checking the Bun version's compatibility with the hardware, examine the build configuration and dependencies for potential conflicts, and ensure your system's software is up-to-date. Further investigation is needed to know what is causing the errors.

Troubleshooting and Possible Solutions

Troubleshooting a segmentation fault requires a systematic approach, combining the information gathered from logs and the setup details. Here's a breakdown of possible solutions and steps to take:

  1. Compatibility Checks: Start by confirming compatibility between the version of Bun and the M3 Pro hardware. Check if there are known issues with the combination of Bun and Apple Silicon, and make sure that there are no known hardware-related problems. Check the Bun documentation and forums for any known compatibility issues or workarounds.
  2. Bun Version: Test different Bun versions, including the latest stable and any beta releases. As the user found the problem happening across multiple versions, this could indicate a deeper problem. Consider downgrading the version to the last stable version if the problem has started recently.
  3. Dependency Inspection: Review the project's dependencies, as shown in package.json. Look for any problematic dependencies, especially those involved in compilation, code transformation, or low-level operations. Try updating or downgrading dependencies to see if a specific package is causing conflicts. Test these dependencies separately to isolate the issue.
  4. Vite Configuration: Examine the vite.config.js file for any unusual configurations or plugins. Some plugins might cause compatibility problems with Bun. Disable plugins one by one to find the problem.
  5. Docker Environment: Confirm the Docker environment is properly configured. Check the resources allocated to the container. Make sure the container has enough memory and CPU resources. Try different Docker build strategies or base images to see if it fixes the problem.
  6. Update and Upgrade: Ensure all software is updated, including MacOS, Docker, and Bun. Sometimes, outdated software causes compatibility issues. Upgrade to the latest versions. Also, check for software updates within the Docker container itself.
  7. Isolate the Issue: Try to isolate the problem by creating a minimal reproducible example. Create a new project with a bare minimum setup that shows the crash. If you can replicate the problem, it simplifies debugging.
  8. Memory Analysis: Use memory analysis tools to identify the cause. Tools such as valgrind (though it may not fully support Bun) or memory profilers can help locate the memory access violations. This step might require building Bun from source for specific debugging symbols.
  9. CPU Instruction Set: Investigate if the build process or the dependencies are using CPU instructions unsupported by the M3 Pro. The SIGILL error may result from an unsupported instruction. Look into the flags passed to the compiler during the build process.
  10. Report the Issue: If none of these steps help, report the issue to the Bun developers. Include detailed information about the system configuration, the steps to reproduce the crash, and the error logs. Providing a clear and complete report is the most helpful thing to solve the problem.

By following these troubleshooting steps, you can try and fix the segmentation fault. Remember to methodically analyze the error and test the solutions, and document everything to keep track of the process. If you follow these suggestions, you will be able to solve your problem.

Key Takeaways and Next Steps

To summarize, the core issue is a segmentation fault in Bun when building a Vite project on an M3 Pro Macbook Pro, specifically within a Docker container. The error is accompanied by a SIGILL (illegal instruction) signal, indicating a potential incompatibility issue. The user has provided detailed information, including steps to reproduce the problem and relevant error logs, which is a great starting point for debugging. It is important to note that the segmentation fault is occurring in the JSC::CodeBlock::finishCreation function, which hints at a deeper problem related to JavaScriptCore.

Here’s a summary of the next steps:

  1. Compatibility Review: Re-examine the compatibility between Bun and the M3 Pro. Look for known issues or workarounds. Check for updates on the versions.
  2. Dependency Review: Carefully inspect the project's dependencies, looking for any which may cause compatibility issues. Update or downgrade the dependencies.
  3. Vite Configuration: Review the vite.config.js file for potential configuration errors or conflicting plugins. Simplify the configuration to see if that helps.
  4. Isolate the Problem: Create a minimal, reproducible example to isolate the problem. This will help understand the specific cause and create a good report.
  5. Deep Dive into Logs: Re-examine the logs and stack traces provided. Investigate any details regarding the CPU instructions to confirm compatibility.
  6. Memory Analysis: Use memory analysis tools, if possible, to find the source of the memory access errors.
  7. Community Help: Seek support from the Bun community through their forums or GitHub issues. Providing clear, detailed information about the problem will enable the community to assist you.

Solving this segmentation fault will likely involve a combination of compatibility checks, dependency analysis, and configuration adjustments. By following these steps and remaining organized, the user can get to the root of the problem and get the build process up and running again. The detailed information provided by the user is very helpful, but a complete solution will need a deeper exploration and testing.

For additional information and community support, you might find the following resources helpful: