2026-08-22 - FreeBSD harvest: the walker ignored its own rule (D191)

Cloned FreeBSD sparse and blobless, re-harvested, and the word list shrank - 147 names lost, six gained. Chasing that found a defect older than the exercise.

is_version_script accepts any .map file, and its doc comment records why: libthr calls its exports pthread.map, and a rule looking for Symbol.map cost every pthread_* name (D127). The harvest command never called it - it tested the filename directly, and had since before D127 was written. The fix landed in the crate and in an example binary; the command anybody actually runs kept the original rule and kept reporting success.

Ten files of fifty-seven were being skipped. Wired up, plus lib/libsys added to the directory list (FreeBSD moved syscall stubs out of libc): 2685 -> 3064 names.

A test caught the consequence exactly as designed. It asserted the absence of clock_gettime with the message "if this now passes, syscall stubs became harvestable and the note above is stale" - and the note claimed, as a fact about the world, that FreeBSD generates syscall stubs at build time so no version script declares them. False: lib/libsys/Symbol.sys.map declares every one. An inference from a search that missed, written down as a property of the source. The assertion is kept and inverted.

Two predictions, both wrong, both from the head of a list

I recommended this as the highest-value action on two grounds and neither held.

• "It will turn ~187 provenance records green." It turned a handful green. The 219 unaccounted are 202 vendor sce* names and 17 C++ ABI names - not syscall wrappers. I read five names off the top of the audit output and generalised to the whole list.
• "It will plausibly name several of the corpus's unnamed imports." It names none of the twenty-six.

Worth doing anyway, for a reason neither prediction named: it surfaced a defect that had been silently degrading every harvest since D127. But the estimates were confident and wrong, from exactly the sampling error that has run through this whole session.