+ // v. tricky now. The THUNK_SELECTOR has been evacuated
+ // by another thread, and is now either EVACUATED or IND.
+ // We need to extract ourselves from the current situation
+ // as cleanly as possible.
+ // - unlock the closure
+ // - update *q, we may have done *some* evaluation
+ // - if evac, we need to call evacuate(), because we
+ // need the write-barrier stuff.
+ // - undo the chain we've built to point to p.
+ SET_INFO(p, (const StgInfoTable *)info_ptr);
+ *q = (StgClosure *)p;
+ if (evac) evacuate(q);
+ unchain_thunk_selectors(prev_thunk_selector, (StgClosure *)p);
+ return;