The position to attribute a node to, preferring real provenance over a synthetic label.
The position to attribute a node to, preferring real provenance over a synthetic label.
a real position resolves to itself (so genuine library/user lines keep their own attribution — no "blame the caller" flip);
the synthetic compile-boundary root resolves to the outermost real entry of its inline chain (inlinedFrom, whose last element is the original user compile(...) call) — real compile-time provenance rather than a guess from tree structure;
if neither is available it stays ScalusSourcePos.empty, leaving the position-fill to fall back to the nearest positioned neighbour.
True when this position carries no useful attribution: either genuinely unknown (isEmpty) or the synthetic compile-boundary root (ScalusSourcePos.syntheticMarkerFile), which is compiler glue rather than user code. The post-optimization position-fill uses this so the program root never wins as a fallback location — generated spine is attributed to the nearest real user code instead of pooling in one fake hot-spot.
True when this position carries no useful attribution: either genuinely unknown (isEmpty) or the synthetic compile-boundary root (ScalusSourcePos.syntheticMarkerFile), which is compiler glue rather than user code. The post-optimization position-fill uses this so the program root never wins as a fallback location — generated spine is attributed to the nearest real user code instead of pooling in one fake hot-spot.