GitNexus/docs/languages/cpp-ingestion-gaps.md

C++ Ingestion Gaps

Audited on 2026-10-23 with freshly built production sources at c35806d24 and the accompanying benchmark changes. See the measurement audit for commands, target checks, exclusions and test limits. Historical reports below remain separate from freshly measured receiver cases; broader ingestion is not exhaustively assessed.

Receiver shape snapshot

States below come from baseline.json. The harness defines each spelling and its N/A reason. RESOLVES requires the exact expected declaration ID and no same-named call to a different owner. WRONG-TARGET records incorrect edges.

Shape	Recorded state	Expression or exclusion
pointerArrowChain	RESOLVES	svc->getUser()->save();
valueDotChain	RESOLVES	svc2.getUser()->save();
plainChain	RESOLVES	svc->getUser()->save();
plainDeepChain	RESOLVES	svc->getUser()->addr.save();
optionalChain	N/A	C++ has no optional-chaining operator.
nonNullAssert	N/A	C++ has no non-null assertion operator.
awaitParen	VISIBLE-GAP	(co_await getUserAsync()).save();
explicitTypeArgs	VISIBLE-GAP	svc->getTyped<User>()->save();
indexElement	RESOLVES	repos[0].save();
fieldReceiverCall	RESOLVES	this->repo.save();
decoratedReceiverBase	N/A	C++ this is implicitly a pointer with no written decoration; the pointer base is measured by pointerArrowChain.
decoratedFieldType	RESOLVES	this->repo->save();

The canonical plainChain now executes svc->getUser()->save() and resolves to User.save; the separate pointer-arrow and value-dot controls also resolve. The old N/A meant duplicate coverage, not a failed plain chain. Deep-chain, indexed and field-receiver cases also reach their exact expected owners. explicitTypeArgs remains a visible gap: reading getTyped<User>() does not generally substitute its declared return type T with User.

Planning candidates

ID	Evidence	Gap or boundary	Next planning step and acceptance
CPP-01	Measured gap	explicitTypeArgs has no call edge and records a receiver drop.	Tie substitutions to the selected declaration and explicit arguments. Test exact owners, ambiguous overloads and unknown mappings; preserve conversion-only suppression.
CPP-02	Boundary audit	Qualified factories, aliases and headers have dedicated regression suites beyond this matrix.	Retain namespace and alias ownership checks while extending templates. Evaluate header classification jointly with C rather than treating the C all-N/A row as success.
CPP-03	Measured gap	(co_await getUserAsync()).save() is VISIBLE-GAP despite an awaiter declaring User await_resume().	Trace coroutine result typing; require User.save and retain an unknown awaiter negative. The minimal C++20 probe passed a compiler syntax check.

Code and regression entry points

• Language provider directory.
• Scope resolver.
• cpp-qualified-template-review.test.ts.
• cpp-qualified-factory-review.test.ts.
• cpp-qualified-receiver-boundaries.test.ts.

Evidence details: receiver baseline notes and current roadmap.