Two orthogonal bugs that compounded to produce the exit_px=±21474836
sentinel in cluster smokes (315 trades baseline, 500 trades pearl):
Bug A — NaN/Inf book propagation:
- apply_snapshot_kernel passes through NaN/Inf prices from MBP-10
predecoded data (session boundaries, gap-fills).
- walk_ask_for_buy / walk_bid_for_sell accumulate cost += take * NaN.
- apply_fill_to_pos: avg_px = NaN; realized_pnl += NaN → permanent NaN.
- Subsequent close: (int)(NaN-derived * 5000) → i32::MAX sentinel.
- Fix: zero-out non-finite levels in apply_snapshot_kernel; add
isfinite() guards in walk helpers as defense-in-depth; ATR update
guards against non-finite mid.
Bug B — pnl_track close branch doesn't reset scratch:
- Scratch reset (full 24-byte memset to 0) was already present in the
current code; no source change required for Bug B.
Tests:
- book_nan_inf_prices_dont_corrupt_realized_pnl: NaN at ask[3] + Inf
at bid[5] survives the fill pipeline without making realized_pnl
non-finite.
- pnl_track_resets_scratch_on_close: open+close+5 flat events emits
exactly 1 record; second open+close emits exactly 1 more (=2 total).
14/14 stop_controller tests pass; all other ml-backtesting test suites
unaffected.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
691dec144e