The PositionManagement redundancy `debug_assert` (position_management.rs:229)
re-derives realized_r from the dense-record columns as
dir*(exit-entry)/|entry-stop| and compared it to the stored value with an
ABSOLUTE < 1e-9 tolerance. At tiny-pip price scale (EURUSD/GBPUSD entry ~1.1,
vol-stop distance ~1e-6) the denominator reconstruction `entry - stop` is a
catastrophic-cancellation subtraction that loses ~6 significant digits; with a
deep gap-through-stop realising a large |R|, the recomputed R drifts from the
(correct) stored realized_r by more than 1e-9 - so a debug build PANICS (exit
101) while a release build (assert compiled out) returns the correct R. GER40
(large pip) never trips it.
Found by the Stage-1 R milestone fieldtest: `aura run --harness stage1-r --real
EURUSD` crashed the headline "score real FX in R" use case on the default (debug)
build, and the debug/release disagreement made the R numbers' validity
unknowable from the public surface.
Root cause (via debug): the stored realized_r uses the cancellation-free FROZEN
latched_dist and is exact - only the guard's tolerance was wrong for small price
scales. Fix: a scale-robust relative tolerance `< 1e-9 * realized.abs().max(1.0)`
(floored at the historical 1e-9 for |R| <= 1, so no change for normal-scale runs).
RED-first: the hermetic synthetic-tiny-pip test
`tiny_pip_gap_stop_does_not_trip_the_redundancy_guard` reproduces the panic and is
pinned here. Verified end-to-end: `aura run --harness stage1-r --real EURUSD` now
returns the R block (exit 0) on a debug build. cargo test --workspace green;
clippy --workspace --all-targets -D warnings clean.
refs #117
Brummel
2ee0d74a8c