+ // To allow access to (ss-5) up to (ss+2), the stack must be oversized.
+ // The former is needed to allow update_continuation_histories(ss-1, ...),
+ // which accesses its argument at ss-4, also near the root.
+ // The latter is needed for statScores and killer initialization.
+ Stack stack[MAX_PLY+8], *ss = stack+5;
+ Move pv[MAX_PLY+1];