The single highest-value fix of the TLC pass (deep-read §1): one native
chain-mutation mutex (addon/ChainOps) held across the FULL Execute() of
every chain worker (LoadPreset/LoadVST/LoadNAM/LoadIR/ReplaceIR) and the
synchronous mutators (clearChain/removeProcessor/moveProcessor). Two
overlapping loadPreset calls can no longer interleave clear()/addProcessor()
into a merged-garbage chain — the plugin-vs-plugin fight becomes
last-writer-wins.
chainGeneration (monotonic, bumped under the mutex) is returned in loadPreset
results and exposed as getChainGeneration (new export, snapshot regenerated),
so the audio-effects executor can detect a foreign write invalidated its
stageSlots map and re-sync instead of flipping bypass/params on wrong slots —
the prerequisite for the single-chain-owner ownership track.
Also rides here: LoadPresetWorker's slot-state restore goes through
setSlotState() instead of const_cast (deep-read §9).
The phase-0 storm test flips from expected-fail to a hard gate: 50 iterations
of concurrent loadPreset now always end with exactly one caller's chain.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Documents TLC deep-read §1: concurrent loadPreset workers interleave
clear()/addProcessor() and merge both presets — reproduces first iteration
([storm-ir-1-0, storm-ir-2-0, storm-ir-2-1]). Quarantined behind
CHAIN_STORM=1; flips to a hard gate when ChainOps lands the serializer
(plan phase 7).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
