[BUG] Crash on Windows 11 arm64: panic: incorrect alignment (Claude Code 2.1.47)

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?

Claude Code crashes on startup/run with a "panic: incorrect alignment" error on Windows 11 arm64.

Environment:

• OS: Windows 11, arm64
• Claude Code version: 2.1.47

Crash report URL:
https://bun.report/1.3.10/W_11423d3cmgEugogCwmzrfg705jBg0vuiBwt1uiB4gyB44wCwvhgmCw236lC4i16lCg6xjkBgsjufCYKERNEL32.DLLg0jCCSntdll.dlloqi1BA0eNrLzEvOLypKTS5RSMzJTM/LTc0rAQBMcwep

Error:
panic: incorrect alignment

What Should Happen?

Claude Code should run without crashing on Windows 11 arm64.

Error Messages/Logs

panic: incorrect alignment

Crash report: https://bun.report/1.3.10/W_11423d3cmgEugogCwmzrfg705jBg0vuiBwt1uiB4gyB44wCwvhgmCw236lC4i16lCg6xjkBgsjufCYKERNEL32.DLLg0jCCSntdll.dlloqi1BA0eNrLzEvOLypKTS5RSMzJTM/LTc0rAQBMcwep

Steps to Reproduce

1. Install Claude Code 2.1.47 on Windows 11 arm64
2. Open Windows Terminal
3. Run claude
4. Claude Code crashes immediately with "panic: incorrect alignment"

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.47 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Architecture: arm64 (Windows 11 on ARM). The crash occurs with "panic: incorrect alignment" — this may be an alignment issue specific to the arm64 architecture in Bun's runtime.