macOS 26.3.2 Intel regression: Codex 0.141.0 and 0.142.4 crash with SIGTRAP in v8::base::OS::SetPermissions

Codex version

Affected versions:

• codex-cli 0.141.0
• codex-cli 0.142.4

Not affected:

• codex-cli 0.139.0

Subscription

• ChatGPT Plus

Model

gpt-5.5

Platform

macOS: 
ProductName:macOS
ProductVersion:26.3.2
BuildVersion:25D2140
Architecture: x86_64
Rosetta translation: Not applicable (Intel Mac)
Hardware: Intel Mac 

Terminal emulator

iTerm.app 3.4.20
[FILL IN: whether the crash also reproduces in the built-in macOS Terminal]

Description

Codex CLI crashes with SIGTRAP immediately after the model invokes the built-in exec JavaScript orchestration tool.

Authentication, the WebSocket connection, and model streaming complete normally. The final Codex log entry is a ToolCall: exec. No tool result is produced, and the process exits with:

[1] 50414 trace trap RUST_LOG=info codex

The macOS crash report shows that Codex's embedded V8 runtime fails while creating a new isolate and configuring its executable code range:

v8::base::OS::SetPermissions
v8::internal::CodeRange::InitReservation
v8::internal::Heap::SetUp
v8::internal::Isolate::Init
v8::Isolate::New

The same machine, configuration, and workflow work correctly after downgrading to Codex CLI 0.139.0. This appears to be a regression introduced after 0.139.0.

Steps to reproduce

1. Install Codex CLI 0.141.0 or 0.142.4.
2. Start Codex:

``bash
RUST_LOG=info codex
``

1. Submit a prompt that causes Codex to invoke the built-in exec tool.
2. Observe that the log ends immediately after ToolCall: exec.
3. Codex exits with trace trap / SIGTRAP before returning the tool result.
4. Downgrade to 0.139.0 and repeat the same workflow; it completes normally.

Expected behavior

The exec tool should create its V8 isolate, execute the JavaScript tool call, return its result, and allow the Codex session to continue.

Actual behavior

Codex terminates with EXC_BREAKPOINT (SIGTRAP) during V8 isolate initialization.

Regression matrix

| Version | Result |
|---|---|
| 0.139.0 | Works normally |
| 0.141.0 | Crashes with SIGTRAP |
| 0.142.4 | Crashes with SIGTRAP |

Troubleshooting performed

• Reinstalled Codex CLI: no change.
• Disabled plugins: no change.
• Reproduced the crash consistently.
• Downgraded to 0.139.0: the crash no longer occurs.
• Authentication and WebSocket requests complete successfully before the crash.

macOS crash report

Exception Type: EXC_BREAKPOINT (SIGTRAP)
Termination Reason: Namespace SIGNAL, Code 5, Trace/BPT trap: 5
Triggered by Thread: 73

Thread 73 Crashed:
0   codex  v8::base::OS::SetPermissions(void*, unsigned long, v8::base::OS::MemoryPermission) + 231
1   codex  v8::internal::CodeRange::InitReservation(v8::PageAllocator*, unsigned long, bool) + 587
2   codex  v8::internal::Heap::SetUp(v8::internal::LocalHeap*) + 399
3   codex  v8::internal::Isolate::Init(...) + 1967
4   codex  v8::internal::Isolate::InitWithSnapshot(...) + 9
5   codex  v8::internal::Snapshot::Initialize(...) + 539
6   codex  v8::Isolate::Initialize(...) + 603
7   codex  v8::Isolate::New(...) + 55
8   codex  v8::isolate::Isolate::new(...) + 103