I just had this happen today. It was indeed a segfault.

From what I could tell it looked like it was in JS code that had been JIT compiled. I haven't attempted to troubleshoot further beyond setting all my future Claude Code instances to pipe their stderr to disk so that I don't lose the stack trace next time.

Bun does not have its own JIT compiler. Bun uses JSC made by Apple. So your blame should be directed to Apple.

And I can believe you because I’ve seen JavaScript-heavy Safari tabs crash.