Understand your first report¶

Output formats¶

abicheck compare prints markdown by default; pass --format json for machine-readable output (CI logic, agents), or --format sarif/html/junit for Code Scanning, standalone reports, or CI test dashboards respectively:

abicheck compare libfoo.so.1 libfoo.so.2 -H foo.h --format json -o result.json

See Output Formats for the full reference (field-by-field JSON schema, SARIF/JUnit details, the review digest).

Exit codes and CI¶

By default, abicheck compare exits with the verdict:

Exit code	Verdict	Meaning
`0`	`NO_CHANGE` / `COMPATIBLE` / `COMPATIBLE_WITH_RISK`	Safe — no binary ABI break
`2`	`API_BREAK`	Source-level API break (binary still works)
`4`	`BREAKING`	Binary ABI break
`64`	—	Invalid invocation (bad args/options, unreadable input) — outside the verdict space

Passing any --severity-* flag switches compare to a different, severity-aware exit-code scheme instead — see Severity Configuration for the full mapping and policy recipes. Other commands add their own codes on top of this space — scan can exit 5 (a --budget time guard tripped) and a multi-library release compare can exit 8 (a library was removed with --fail-on-removed-library). The full per-command matrix, including compat mode, is the Exit Codes reference.

Suppressions/policies/baselines all interact with the same pipeline before the exit code is computed — see CI Gating for how those pieces fit together, and the GitHub Action for the fastest way to wire this into CI (it installs Python/castxml/abicheck and runs the comparison in a few lines of YAML).

Next¶

➡️ Choose Your Workflow — map your artifacts and CI policy to the exact command for ongoing use.