Drew T
2.1 KiB
§400 ★★ — A BASELINE CHECK THAT CONFLATES "ABSENT EVERYWHERE" WITH "CHANGED UNDER US" SILENTLY DROPS NEW FILES (P31 S69; 8 files, one session)
parallel_gate refuses to adopt a worker's file when the main tree's copy no longer matches the
pinned baseline — the guard the whole tool exists for. It compared:
base = sh(["git","show", "%s:%s" % (pin, path)]).stdout # "" when the path is NOT at the pin
cur = open(path).read() if os.path.exists(path) else None # None when absent from the main tree
if cur != base: REFUSE
A jtbl carve splits a TU, creating src/<bin>/<bin>_jr_<addr>.c that exists at neither the pin
nor the main tree. That is None != "" → refused as "main tree moved under them", and never
added. Eight accumulated in one session.
Why it stayed invisible — this is the instructive part. Nothing failed locally: the file is on
disk, the build finds it, check-all goes green. But config/splat.<bin>.yaml names the subseg and
IS committed, and 31 sibling _jr_ files in that binary are tracked — so a fresh clone gets the
config without the source. The defect only surfaced when a later run's dirty-tree guard refused to
start and listed them.
The fix: distinguish not present at the pin from empty at the pin using git show's RETURN
CODE, so absent-in-both compares equal and the file adopts. Report new adoptions explicitly — adding
a brand-new source file must never be silent (R32).
The general law: when a comparison uses two different sentinels for "nothing" ("" from a failed
command, None from a missing file), it will report a difference that does not exist — and in a
guard, a phantom difference becomes a refusal, which looks exactly like the guard working correctly.
Check what your "absent" value IS on both sides before trusting an inequality.
Corollary for carve state: the standing rule is never blanket-add config/overlays.mk or the
splat yamls (they are shared state). That rule does NOT extend to a carve's own new source file —
that file is per-binary, is named by a committed yaml, and MUST be adopted with the bank that
created it.