Index: src/vdbe.c
==================================================================
--- src/vdbe.c
+++ src/vdbe.c
@@ -4512,10 +4512,11 @@
   VdbeCursor *pC;
   int res;
 
   pC = p->apCsr[pOp->p1];
   assert( isSorter(pC) );
+  res = 0;
   rc = sqlite3VdbeSorterNext(db, pC, &res);
   goto next_tail;
 case OP_PrevIfOpen:    /* jump */
 case OP_NextIfOpen:    /* jump */
   if( p->apCsr[pOp->p1]==0 ) break;