[BUG] Bun panic: invalid enum value on Windows win11_dt + WSL reg.exe ENOEXEC error

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?

Running claude on Windows 11 (win11_dt) causes Bun to crash:

panic(main thread): invalid enum value
Bun v1.3.13 Windows x64 (baseline)

Also tried WSL2 (Ubuntu) but got:
ENOEXEC: unknown error, posix_spawn '/mnt/c/Windows/System32/reg.exe'

Claude Code cannot be used on this machine at all.

What Should Happen?

Running claude on Windows 11 (win11_dt) causes Bun to crash:

panic(main thread): invalid enum value
Bun v1.3.13 Windows x64 (baseline)

Also tried WSL2 (Ubuntu) but got:
ENOEXEC: unknown error, posix_spawn '/mnt/c/Windows/System32/reg.exe'

Claude Code cannot be used on this machine at all.

Error Messages/Logs

Steps to Reproduce

Running claude on Windows 11 (win11_dt) causes Bun to crash:

panic(main thread): invalid enum value
Bun v1.3.13 Windows x64 (baseline)

Also tried WSL2 (Ubuntu) but got:
ENOEXEC: unknown error, posix_spawn '/mnt/c/Windows/System32/reg.exe'

Claude Code cannot be used on this machine at all.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.118 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_