Executable Global Source Missing-Block Gate
Result
The global normalization--Cech source remains unconstructed, but its construction boundary is now executable. The checker research/voevodsky/check_global_normalization_cech_source_gate.rs records the known local packets separately and represents every absent comparison by a typed MissingBlock value.
There is intentionally no default value, zero-matrix conversion, or multiplication operation for MissingBlock. An absent geometric morphism therefore cannot be silently interpreted as a zero block in a global differential.
Earliest missing geometry
The first non-formal datum is the marked ringed-support correspondence
together with its reflected minus-side correspondence. Entry 105 proves that literal pullback along the carrier gives zero while the local trace in entry 100 is nonzero, so ordinary restriction and a literal Cousin boundary cannot supply this datum. The checker names the resulting typed obligation d_central_flip.
Retained obligations
The executable gate lists seven unresolved blocks: occurrence/Rees and Tor/Cech totalization differentials, the central-flip correspondence, two endpoint comparisons, the full-log carrier comparison, and the central exceptional two-to-one row.
Known packet ranks are emitted for audit while global source ranks remain unknown. Global d-squared, Lz=b, Smith normal form, and the endpoint-fixed mapping fiber therefore are not run.
Scope
This is a construction-order invariant, not a nonexistence theorem. Filling every finite block would yield at most a filtered chain candidate; it would not by itself prove a six-functor kernel, extraordinary base change, properness, physical parity, or a source identity.
Delegated read-only audits: run-1e3011cd00324c848dc4d5d0ef5035d7 and run-fa505c830469430292b1a19a1e7502eb.