Index: src/vdbesort.c
==================================================================
--- src/vdbesort.c
+++ src/vdbesort.c
@@ -827,11 +827,11 @@
   KeyInfo *pKeyInfo;              /* Copy of pCsr->pKeyInfo with db==0 */
   int szKeyInfo;                  /* Size of pCsr->pKeyInfo in bytes */
   int sz;                         /* Size of pSorter in bytes */
   int rc = SQLITE_OK;
 #if SQLITE_MAX_WORKER_THREADS==0
-  const int nWorker = 0;
+# define nWorker 0
 #else
   int nWorker = (sqlite3GlobalConfig.bCoreMutex?sqlite3GlobalConfig.nWorker:0);
 #endif
 
   assert( pCsr->pKeyInfo && pCsr->pBt==0 );
@@ -877,10 +877,11 @@
     }
   }
 
   return rc;
 }
+#undef nWorker   /* Defined at the top of this function */
 
 /*
 ** Free the list of sorted records starting at pRecord.
 */
 static void vdbeSorterRecordFree(sqlite3 *db, SorterRecord *pRecord){
@@ -1804,13 +1805,12 @@
   SortSubtask *pTask, 
   MergeEngine *pMerger,
   IncrMerger **ppOut
 ){
   int rc = SQLITE_OK;
-  IncrMerger *pIncr = *ppOut = (IncrMerger*)sqlite3_malloc(sizeof(IncrMerger));
+  IncrMerger *pIncr = *ppOut = (IncrMerger*)sqlite3MallocZero(sizeof(*pIncr));
   if( pIncr ){
-    memset(pIncr, 0, sizeof(IncrMerger));
     pIncr->pMerger = pMerger;
     pIncr->pTask = pTask;
     pIncr->mxSz = MAX(pTask->pSorter->mxKeysize+9,pTask->pSorter->mxPmaSize/2);
     pTask->file2.iEof += pIncr->mxSz;
   }else{