Dependency static/dynamic linking-mode change has no ChangeKind

Index: Known gaps

Status (re-verified 2026-10-25): OPEN. docs/contribute/abi-taxonomy-coverage.md:177 still lists dependency-abi.linking-mode-change as NOT_IMPLEMENTED, and no ChangeKind containing linking_mode exists in abicheck/model/change_catalog.

Found by Phase 2/3 of ABI/API knowledge and corpus — the one taxonomy leaf (dependency-abi.linking-mode-change, docs/contribute/abi-api-failure-taxonomy.md) that no ChangeKind claims at any evidence tier, and therefore the only NOT_IMPLEMENTED row in the coverage matrix.

When a dependency switches between static and dynamic linking, the dependency's own symbols change status wholesale: previously resolved at load time through DT_NEEDED (or the PE import table / Mach-O load commands), they are now duplicated into the artifact itself, with their own visibility, ODR exposure, and interposition behaviour changing with them — and the reverse when a vendored dependency is unbundled. Nothing in the registry names that transition. Its consequences are partly observable through unrelated kinds — needed_removed when the dependency leaves the needed list, symbol_leaked_from_dependency_changed / visibility_leak when its symbols surface in the artifact's own export table — so a real occurrence produces two or three findings that each describe a symptom and none of which says what happened.

Not fixed here: Phase 2/3 of that plan is a mapping and classification pass, and the plan's own "Out of scope" section rules out any detector, evidence, or ChangeKind change (a NOT_IMPLEMENTED finding is recorded, not fixed, by it). Tractable when it is picked up: both sides' needed/import lists and export sets are already collected at L0, so the evidence a detector would join is present today — what is missing is the join, a kind, and the "vendored vs. unbundled" direction in its impact text. Note the adjacent, deliberately unclaimed half: whether the newly-static dependency's code is ABI-compatible with what consumers already linked is a question about a third artifact abicheck was not given, which is dependency-abi.transitive-break's territory, not this leaf's.