[BUG] Claude Code 2.1.243 immediately segfaults on Arch Linux x86_64

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 2.1.243 immediately crashes with a segmentation fault on Arch Linux x86_64.

The crash occurs before Claude Code starts and even happens when running claude --version, so it does not appear to be related to a project, configuration, MCP server, or Claude model.

Claude Code 2.1.241 works correctly on the exact same system and installation, making this appear to be a regression in 2.1.243.

What Should Happen?

claude --version should print the installed Claude Code version, and claude should start normally.

Version 2.1.241 behaves correctly on the same machine.

Error Messages/Logs

$ claude --version
Segmentation fault (core dumped)

The kernel reports:
claude[5903]: segfault at 0 ip 0000000001d10458 sp 00007ffc46cae2c0 error 4 in 2.1.243[1b0f458,1953000+3b33000] likely on CPU 5 (core 5, socket 0)

Code: cc cc 55 48 89 e5 48 89 fe 48 8b 05 82 19 78 03 48 89 f9 48 c1 e9 1d 48 8b 84 c8 80 00 00 00 89 f1 c1 e9 0d 81 e1 f8 ff 00 00 <48> 8b 3c 08 48 85 ff 74 1e 48 8b 07 64 48 33 04 25 00 00 00 00 75

A second invocation produced the same crash at the same instruction address:
claude[14070]: segfault at 0 ip 0000000001d10458 sp 00007ffd86b15ce0 error 4 in 2.1.243[1b0f458,1953000+3b33000] likely on CPU 9 (core 1, socket 0)

Steps to Reproduce

Use an Arch Linux x86_64 system.

Install Claude Code using the official native installer.

Update Claude Code to version 2.1.243.

Run:

claude --version

Observe:

Segmentation fault (core dumped)

Verify the installed binary:

readlink -f ~/.local/bin/claude

Output:

/home/ripple/.local/share/claude/versions/2.1.243

Run the previous installed version directly:

~/.local/share/claude/versions/2.1.241 --version

Version 2.1.241 successfully outputs:

2.1.241 (Claude Code)

Pointing the claude symlink back to 2.1.241 restores functionality:

ln -sf ~/.local/share/claude/versions/2.1.241 ~/.local/bin/claude

Then:

\$ claude --version
2.1.241 (Claude Code)

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.241

Claude Code Version

2.1.243 (Claude Code)

Platform

Other

Operating System

Other Linux

Terminal/Shell

Other

Additional Information

Claude Code is installed using the official native installer.

The installation maintains multiple versions under:

~/.local/share/claude/versions/

The installed versions at the time of testing were:

• 2.1.238
• 2.1.240
• 2.1.241
• 2.1.243

The claude executable is a symbolic link:

~/.local/bin/claude -> ~/.local/share/claude/versions/2.1.243

The issue can be reproduced without opening a project or loading any Claude Code configuration.

The crash occurs immediately when executing the 2.1.243 binary:

~/.local/share/claude/versions/2.1.243 --version

While the previous version works:

~/.local/share/claude/versions/2.1.241 --version

Result:

• 2.1.243 -> Segmentation fault
• 2.1.241 -> Works normally

The kernel reports the segmentation fault occurring inside the 2.1.243 executable itself.

The crash has occurred on different CPU cores across separate invocations:

• Likely on CPU 5 (core 5, socket 0)
• Likely on CPU 9 (core 1, socket 0)

This makes the issue highly reproducible and appears to indicate a problem specific to the 2.1.243 binary/runtime on this environment rather than a project-specific configuration issue.

curl -fsSL https://claude.ai/install.sh | bash -s 2.1.241

// .claude/setting.json
{
  "env": {
    "DISABLE_AUTOUPDATER": "1"
  }
}

$ ~/.local/share/claude/versions/2.1.243 --version
$ echo $?
139

claude[901409]: segfault at 0 ip 0000000001d10458 sp 00007ffe30f97a90 error 4 in 2.1.243[1b0f458,1953000+3b33000]
claude[901451]: segfault at 0 ip 0000000001d10458 sp 00007ffd4816c4c0 error 4 in 2.1.243[1b0f458,1953000+3b33000]
claude[901640]: segfault at 0 ip 0000000001d10458 sp 00007ffeb50634e0 error 4 in 2.1.243[1b0f458,1953000+3b33000]

ln -sfn ~/.local/share/claude/versions/2.1.241 ~/.local/bin/claude
claude --version   # 2.1.241 (Claude Code)

Linux  7.2.0-1-cachyos #1 SMP PREEMPT_DYNAMIC Thu, 20 Aug 2026 06:06:30 +0000 x86_64 GNU/Linux

ln -sf ~/.local/share/claude/versions/2.1.241 ~/.local/bin/claude

claude --version

2.1.241 (Claude Code)