[BUG] V8 JavaScript engine crash inside the Claude Code CLI binary

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?

I'm seeing intermittent crashes using the Claude Code CLI due to the V8 JavaScript engine.

What Should Happen?

No V8 JavaScript engine crash.

Error Messages/Logs

#
# Fatal error in , line 0
# unreachable code
#
#
#
#FailureMessage Object: 0x7622b59f9c00
----- Native stack trace -----

 1: 0xff7201  [claude]
 2: 0x2862b6b V8_Fatal(char const*, ...) [claude]
 3: 0x1aff076  [claude]
 4: 0x2ecb2f8 v8::internal::compiler::turboshaft::V<v8::internal::String> v8::internal::compiler::turboshaft::TurboshaftAssemblerOpInterface<v8::internal::compiler::turboshaft::ReducerStack<v8::internal::compiler::turboshaft::Assembler<v8::internal::compiler::turboshaft::reducer_list<v8::internal::compiler::turboshaft::TurboshaftAssemblerOpInterface, v8::internal::compiler::turboshaft::GraphVisitor, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >, false, v8::internal::compiler::turboshaft::GraphVisitor, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >::LoadFieldImpl<v8::internal::String>(v8::internal::compiler::turboshaft::OpIndex, v8::internal::compiler::FieldAccess const&) [claude]
 5: 0x2eedf1d v8::internal::compiler::turboshaft::MachineLoweringReducer<v8::internal::compiler::turboshaft::ReducerStack<v8::internal::compiler::turboshaft::Assembler<v8::internal::compiler::turboshaft::reducer_list<v8::internal::compiler::turboshaft::TurboshaftAssemblerOpInterface, v8::internal::compiler::turboshaft::GraphVisitor, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >, false, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >::ReduceStringAt(v8::internal::compiler::turboshaft::V<v8::internal::String>, v8::internal::compiler::turboshaft::V<v8::internal::compiler::turboshaft::WordWithBits<64ul> >, v8::internal::compiler::turboshaft::StringAtOp::Kind) [claude]
 6: 0x2ef8d7f v8::internal::compiler::turboshaft::OpIndex v8::internal::compiler::turboshaft::GraphVisitor<v8::internal::compiler::turboshaft::ReducerStack<v8::internal::compiler::turboshaft::Assembler<v8::internal::compiler::turboshaft::reducer_list<v8::internal::compiler::turboshaft::TurboshaftAssemblerOpInterface, v8::internal::compiler::turboshaft::GraphVisitor, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >, false, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >::VisitOpNoMappingUpdate<false>(v8::internal::compiler::turboshaft::OpIndex, v8::internal::compiler::turboshaft::Block const*) [claude]
 7: 0x2efa9ac void v8::internal::compiler::turboshaft::GraphVisitor<v8::internal::compiler::turboshaft::ReducerStack<v8::internal::compiler::turboshaft::Assembler<v8::internal::compiler::turboshaft::reducer_list<v8::internal::compiler::turboshaft::TurboshaftAssemblerOpInterface, v8::internal::compiler::turboshaft::GraphVisitor, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >, false, v8::internal::compiler::turboshaft::JSGenericLoweringReducer, v8::internal::compiler::turboshaft::DataViewLoweringReducer, v8::internal::compiler::turboshaft::MachineLoweringReducer, v8::internal::compiler::turboshaft::FastApiCallLoweringReducer, v8::internal::compiler::turboshaft::SelectLoweringReducer, v8::internal::compiler::turboshaft::MachineOptimizationReducer, v8::internal::compiler::turboshaft::TSReducerBase> >::VisitAllBlocks<false>() [claude]
 8: 0x2efc9ca  [claude]
 9: 0x2997274 auto v8::internal::compiler::PipelineImpl::Run<v8::internal::compiler::turboshaft::MachineLoweringPhase>() [claude]
10: 0x29ae081 v8::internal::compiler::PipelineImpl::OptimizeGraph(v8::internal::compiler::Linkage*) [claude]
11: 0x29afae0 v8::internal::compiler::PipelineCompilationJob::ExecuteJobImpl(v8::internal::RuntimeCallStats*, v8::internal::LocalIsolate*) [claude]
12: 0x127e33b v8::internal::OptimizedCompilationJob::ExecuteJob(v8::internal::RuntimeCallStats*, v8::internal::LocalIsolate*) [claude]
13: 0x12bd671 v8::internal::OptimizingCompileDispatcher::CompileNext(v8::internal::TurbofanCompilationJob*, v8::internal::LocalIsolate*) [claude]
14: 0x12bda0f v8::internal::OptimizingCompileDispatcher::CompileTask::Run(v8::JobDelegate*) [claude]
15: 0x21bf548 v8::platform::DefaultJobWorker::Run() [claude]
16: 0xff73d4  [claude]
17: 0x7622b729caa4  [/lib/x86_64-linux-gnu/libc.so.6]
18: 0x7622b7329c6c  [/lib/x86_64-linux-gnu/libc.so.6]
Illegal instruction (core dumped)

Steps to Reproduce

1. Lunch Claude Code CLI via WSL.
2. CD to project (Visual Studio project)
3. Launch CC.
4. Prompt.
5. V8 JavaScript engine crash.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.71

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

WSL (Windows Subsystem for Linux)

Additional Information

_No response_