v2.1.70: Deterministic SIGTRAP crash in Bun HTTP Client thread (3 crashes, identical stack)

Summary

Claude Code v2.1.70 crashes with EXC_BREAKPOINT/SIGTRAP on the Bun "HTTP Client" thread. This is a deterministic bug — all 3 crashes have an identical call stack and crash at the same offset (0x3220190). No crashes were observed with v2.1.68 or v2.1.69.

Environment

• Claude Code: 2.1.70
• Embedded Bun: v1.3.11 (dea015ec) macOS Silicon
• macOS: 26.2 (25C56), Apple Silicon (Mac16,5 — MacBook Pro M4 Max)
• Previous versions: 2.1.68 (Bun build 548644af) and 2.1.69 (Bun build dea015ec) — zero crashes

Crash Details

Three crashes on the same day, with session durations of 3 min, 16 min, and 68 min (ruling out long-session / memory-pressure as the cause):

| # | Session duration | Faulting thread | Exception |
|---|---|---|---|
| 1 | ~3 min | Thread 23 (HTTP Client) | EXC_BREAKPOINT/SIGTRAP |
| 2 | ~16 min | Thread 23 (HTTP Client) | EXC_BREAKPOINT/SIGTRAP |
| 3 | ~68 min | Thread 24 (HTTP Client) | EXC_BREAKPOINT/SIGTRAP |

Identical faulting stack (all 3 crashes):

claude       0x3220190    ← EXC_BREAKPOINT here
claude       0x320fbb8
claude       0x57571c
libsystem_platform.dylib  _sigtramp
libsystem_c.dylib         strdup
claude       0x14e8074
claude       0xf04330
claude       0xf58cd8
claude       0xf05640
claude       0xe56738
claude       0x14eadd8
claude       0x14e96e4
claude       0x14e97fc
claude       0xd4ce50
claude       0xaa066c
libsystem_pthread.dylib   _pthread_start
libsystem_pthread.dylib   thread_start

Analysis

• EXC_BREAKPOINT = deliberate assertion/trap (not random memory corruption). Bun's code hits an unreachable() or assert(false).
• Thread name HTTP Client = Bun's internal HTTP networking thread (communicates with Anthropic API).
• strdup in stack = crash occurs during string handling in HTTP response/request processing.
• Bun build changed from 548644af (v2.1.68) to dea015ec (v2.1.69+), but crashes only appear in v2.1.70, suggesting the JS bundle in 2.1.70 triggers a new HTTP code path.

Bun crash report URL

From the panic output:

https://bun.report/1.3.11/M_1dea015emgE+hogD__mng6pB+yhheutm2e+jrheuzz1cu926pBmur6pB2/r6pB+knza2mjoV__A2k2wxujDgm39svB

macOS crash reports

Full .ips crash reports are available — happy to upload if needed. The three reports are byte-for-byte identical in their stack traces.

Impact

Each crash terminates the Claude Code process immediately, losing the current session. The user must restart and re-authenticate. Work in progress (uncommitted edits, running pipelines) may be lost.