Segfault regression at 2.1.242 on glibc 2.44 (Arch) — distinct from closed #62747

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported as a fresh regression
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Code segfaults immediately on startup (claude --version never prints, exit 139) on very recent glibc. This looks related to #62747, but that issue was closed as fixed in 2.1.197, and the regression window I bisected is completely different — suggesting either a reintroduced regression or a distinct bug with an identical symptom.

Environment

• Distro: Arch Linux (rolling release)
• Kernel: 7.1.9-arch1-2
• glibc: 2.44
• CPU: Intel i5-11260H (full AVX2/AVX-512 — ruling out the separate CPU-feature crash reported elsewhere)
• Install method: npm (@anthropic-ai/claude-code)

Steps to Reproduce

1. npm install -g --allow-scripts=@anthropic-ai/claude-code @anthropic-ai/claude-code@2.1.242
2. claude --version
3. Segfaults immediately, no output

Bisection

Tested each version explicitly via npm install + claude --version:

• ✅ 2.1.212 — works
• ✅ 2.1.228 — works
• ✅ 2.1.235 — works
• ✅ 2.1.239 — works
• ✅ 2.1.241 — works
• ❌ 2.1.242 — segfaults
• ❌ 2.1.243 — segfaults

Is this a regression?

Yes — exact boundary is 2.1.241 (works) → 2.1.242 (broken).

Related issues

• #62747 — same symptom (immediate SIGSEGV, Bun runtime), closed as fixed in 2.1.197. A separate user (@nic116seitz) commented there recently on Arch/glibc 2.44 reporting the crash persists even on 2.1.205, which is inconsistent with that fix. This report's own bisection (2.1.241→2.1.242) is a third, distinct regression window from either of those, which is why I'm filing separately rather than adding a fourth comment to a closed thread.

Happy to test any candidate fix or provide a coredump/backtrace if useful.