D021 - Symbols carry which console generation they belong to

assumed · 2026-08-19

Every census group declares OBS_SHARED, OBS_PREVIOUS, OBS_CURRENT or OBS_AVAILABILITY_UNKNOWN, and the sym record carries it.

Without it "absent" means two incompatible things: the function does not exist on this generation, which is correct and not a gap; or it exists and the platform has not implemented it, which is work. Counted together, the coverage figure means nothing - the same mistake the census control guards against, one level up.

The census verdict changes accordingly. A library belonging to the other generation scores skip rather than fail when wholly absent, because scoring it red buries the real gaps under absences that are correct.

What it exposed immediately: of 329 censused symbols, 312 are shared, 17 belong to the previous generation only, and none are specific to the current one. That is the honest state of this program as a current-generation probe, and it was invisible until the field existed.

OBS_AVAILABILITY_UNKNOWN is offered deliberately. Assuming shared for something uncertain silently reclassifies a real gap as an expected absence, which is the exact failure this decision exists to prevent.