[cpp-RCP-N2-04] DAL-B coverage report has zero branch coverage instrumentation yet asserts a 100% threshold #67

Location: coverage-report.json — top-level dal/thresholdBranch fields and summary block.

Finding: The committed coverage report declares a DAL-B target and a 100% branch-coverage threshold, but its own summary reports zero total branches measured (totalBranches: 0, hitBranches: 0) and every per-file entry shows branchesTotal: 0. No branch/decision coverage data was actually collected by whatever produced this report — the branch-coverage gate is measuring a 0/0 ratio, which is vacuously "nothing failed" rather than "100% met." DAL-B (and the repo's stated ASIL-B target) requires real branch/decision coverage evidence, and this report currently provides none while still reporting a pass/fail judgement.

Recommendation: Enable branch/decision coverage collection in whatever generates coverage.info (e.g. lcov's branch-coverage flag or the equivalent gcov instrumentation) so totalBranches is nonzero, and make the CI gate that consumes this report treat "no branch data collected" as a failure rather than a vacuous pass.

Verification: Independently re-read coverage-report.json from current HEAD (commit 4b9449a, 2026-07-29). Confirmed summary.totalBranches and summary.hitBranches are both 0, thresholdBranch is 100.0, and dal is "DAL-B".

Filed from the 2026-07-29 ecosystem audit register; independently re-verified against current HEAD before filing.