Troubleshooting

Symptom	Action
Cargo rejects the toolchain or edition	Install Rust with rustup and use the pinned rust-toolchain.toml; a distribution Cargo can be older.
Example input not found	Run from the repository root and use the complete fixture paths in the quickstart.
REVISION_CONFLICT, exit 4	Read rusteda show/log, then reassess the change against the current explicit revision.
HEAD rejected as a mutation base	Pass the concrete revN; queries can use HEAD.
BACKEND_UNAVAILABLE / A0501	Check the compiled features, NVIDIA driver, NVRTC and device self-test; start with --backend cpu.
No path for a handle	Use a handle returned for the same revision and corner; check unconstrained endpoints and path limits.
Unsupported SDC diagnostic	Check supported scope and the SDC specification; remove or replace a constraint only if its semantics remain valid.
Old sta.rbin format rejected	Run timing again with the current engine; the current engine writes STA v2.
Checker is undecided or disagrees	Keep the artifact and diagnostics, reduce the case, and compare with a pinned black-box reference; see checking.
Memory budget reached	Reduce corners/workers/path limits, inspect tag growth, and use OS guards; a larger state budget requires a new estimate.

For a reproducible report include the command, version, error code, input hashes, corner, wire model, backend, precision, memory limits and smallest shareable input. Follow the repository's security policy for vulnerabilities or confidential design data.