[BUG] Claude Code crashes with panic: incorrect alignment on Windows ARM64 (exit code 3)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Environment:

• OS: Windows 11 ARM64 (win11_dt)
• Extension version: anthropic.claude-code-2.1.49-win32-arm64
• Bun runtime (embedded): v1.3.10
• CPU: ARM64 (neon fp aes crc32 atomics)

The Claude Code process crashes with a Bun runtime panic after ~85 seconds of operation, producing exit code 3. The crash message is:

panic(thread 22672): incorrect alignment

oh no: Bun has crashed. This indicates a bug in Bun, not your code.

What Should Happen?

Claude Code should run stably without crashing. The process should not panic due to memory alignment issues on Windows ARM64.

Bun crash report URL:
https://bun.report/1.3.10/W_11423d3cmgEugogCwmzrfwl0uiBgyvBw32CwmvBo7xB44wCwvhgmCw236lC4i16lCg6xjkBgsjufCYKERNEL32.DLLg0jCCSntdll.dlloqi1BA0eNrLzEvOLypKTS5RSMzJTM/LTc0rAQBMcwep

Impact:

Bash/shell tool execution is non-functional
Long sessions get interrupted by crashes and force a restart

Error Messages/Logs

Steps to Reproduce

Title: Claude Code crashes with panic: incorrect alignment on Windows ARM64 (exit code 3)

Environment:

OS: Windows 11 ARM64 (win11_dt)
Extension version: anthropic.claude-code-2.1.49-win32-arm64
Bun runtime (embedded): v1.3.10
CPU: ARM64 (neon fp aes crc32 atomics)
What's wrong:
The Claude Code process crashes with a Bun runtime panic after ~85 seconds of operation, producing exit code 3. The crash message is:

panic(thread 22672): incorrect alignment

oh no: Bun has crashed. This indicates a bug in Bun, not your code.
What should happen:
Claude Code should run stably without crashing. The process should not panic due to memory alignment issues on Windows ARM64.

Bun crash report URL:
https://bun.report/1.3.10/W_11423d3cmgEugogCwmzrfwl0uiBgyvBw32CwmvBo7xB44wCwvhgmCw236lC4i16lCg6xjkBgsjufCYKERNEL32.DLLg0jCCSntdll.dlloqi1BA0eNrLzEvOLypKTS5RSMzJTM/LTc0rAQBMcwep

Impact:

Bash/shell tool execution is non-functional
Long sessions get interrupted by crashes and force a restart

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Code version: 2.1.49 (win32-arm64)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_