SLCI Inspection Incompatibility Analysis

Analyze SLCI code inspection results and trace failures back to compatibility constraint violations or known limitations by matching failed code lines against known incorrect code generation patterns and documented limitation scenarios.

When to Use

• User asks why SLCI inspection failed or has verification errors
• User wants to trace inspection failures to their root-cause settings
• User has an inspection report with Failed/Error/Unverified items
• User asks to diagnose code inspection issues before re-running
• User wants to understand which compatibility settings caused inspection failure

When NOT to Use

• User wants to check model compatibility before running inspection (no inspection failure context) — use slci-compatibility-analysis instead
• User confirms the inspection failure is not related to a compatibility issue
• User wants general Simulink model building or code generation help

Workflow

0. Clarify Intent

Ask the user whether the inspection failure might be related to a compatibility issue before taking any other action. Do not search for files or run MATLAB until the user confirms.

• Yes → proceed to Step 1.
• No → stop this skill.
• Unsure → explain what compatibility issues are and ask again.

1. Locate the Inspection Report

Get the report folder from MATLAB:

c = slci.Configuration('<model_name>');
reportFolder = c.getReportFolder();

Look for <model_name>_report.html (or .pdf/.doc). If found, compare the model's timestamp against the report's — warn if the report may be stale.

If the report does NOT exist, stop and warn the user. Suggest c.inspect(). If the user explicitly asks to run inspection, first check whether generated code is stale or missing and regenerate if needed before inspecting.

Code regeneration commands (used throughout this skill):

• Top model: rtwbuild('<model_name>')
• Reference model: c.setTopModel(false); slbuild('<model_name>', 'ModelReferenceRTWTargetOnly')

Pre-inspection settings: If the user asks for advanced loop analysis support, set c.setApplyAdvancedLoopSupport(true) before calling c.inspect(). This enables verification of algebraic loop constructs that SLCI skips by default.

2. Parse the Inspection Report

Extract the text content and search for items with Failed, Error, or Unverified status, capturing 2 lines of context before and 5 lines after each match.

For each failed item, identify:

• The code file and line number where verification failed
• The block path the code maps to (from comments)
• The failure reason (e.g., "unable to verify", "no traceability", "ambiguous mapping")

3. Read the Failed Code Lines

For each failed code location, read the generated C source file at the failed line, capturing 5–10 lines of surrounding context to understand the pattern.

Generated code is located at:

• Top model: <model_dir>/<model_name>_ert_rtw/<source_file>.c
• Reference model: <model_dir>/slprj/ert/<model_name>/<source_file>.c

For Stateflow failures, consult stateflow_failure_patterns.md for traceability comment format, merge junction patterns, and a quick-triage table before reading full constraint reference files.

4. Match Against Incorrect Code Generation Patterns

Read the constraint files from the slci-compatibility-analysis skill's references/ folder.

See the Constraint Categories table in slci-compatibility-analysis for the full list of constraint files and their categories.

For each failed code line, use the block path from its traceability comment to identify the block type, then compare the code against the constraint descriptions and Why explanations in the matching constraint files.

Critical: Verify applicability before declaring a match. A structural resemblance alone is NOT sufficient. For each candidate match, verify:

1. Scope: Does the constraint apply to the specific block type in the failing model?
2. Mechanism: Does the constraint's parameter actually control the observed code generation behavior? Read the Why section in the constraint entry to confirm.
3. Contradictions: Check whether another constraint gives opposing guidance for the same scenario.

If no constraint satisfies all three checks, report the unmatched failures to the user and ask whether to proceed to Step 4b (limitation matching). If the user declines, classify those failures as UNMATCHED and include them in the report with the constraints that were considered and why each was ruled out. Do NOT check limitations without explicit user approval.

4b. Match Against Known Limitations (requires user permission)

Only run this step after the user has approved proceeding from Step 4.

Compare unmatched failures against known limitations in the slci-compatibility-analysis skill's references/code_inspection_limitations.md. Constraint violations take priority — only classify as LIMITATION if no constraint is a better explanation. If the failure matches neither a constraint nor a limitation, classify as UNMAPPED and document why each candidate was ruled out. Do NOT report a "closest match" as the root cause — an incorrect mapping is worse than an honest "unmapped."

5. Cross-Reference with Compatibility Report

Skip this step if inspection was terminated (e.g., missing headers or compile errors).

Use slci-compatibility-analysis to obtain or verify compatibility results. Cross-reference the compatibility warnings against the matched constraints to confirm the mapping. When a warning could map to multiple conditions, check the model's actual settings to identify the true trigger rather than relying on the warning text alone.

6. Present Results

In the context window, show only a brief summary table (columns: #, Location, Pattern, Root Cause, Type) and summary counts.

Save detailed results to: <model_dir>/<model_name>_inspection_analysis_YYYY-MM-DD.md

If constraint violations were found, ask the user if they want to apply fixes. If yes, delegate to the slci-compatibility-analysis skill to apply fixes, then regenerate code and re-run c.inspect(). Do not fix the model yourself — no set_param, no fixIncompatibilities, no model modifications of any kind.

If failures remain after fixes, re-run this analysis on the fixed model. If only UNMATCHED, UNMAPPED, or LIMITATION failures remain, inform the user that automatic fixing is not possible.

If no failed items are found, inform the user that all checks passed and save a brief report. If compatibility warnings exist despite passing, include a Warning Impact Analysis explaining why each warning did not cause a failure and under what conditions it could become one.

Guardrails

• NEVER skip Step 0 (Clarify Intent). You must ask the user whether the failure is compatibility-related and receive confirmation before taking any diagnostic action. Do not search for files, run MATLAB, or read reports until the user confirms.
• NEVER report a "closest match" as a root cause. An incorrect mapping is worse than an honest "unmapped." All three checks (scope, mechanism, contradictions) must pass before declaring a constraint match.
• NEVER check limitations without explicit user permission. Step 4b requires the user to approve before proceeding.
• NEVER apply fixes directly. This skill only diagnoses — it does not modify the model. Delegate all fix application to slci-compatibility-analysis. If that skill is unavailable, stop.

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