Index: src/expr.c
==================================================================
--- src/expr.c
+++ src/expr.c
@@ -4688,12 +4688,11 @@
             testcase( (pDef->funcFlags & OPFLAG_BYTELENARG)==OPFLAG_BYTELENARG);
             pFarg->a[0].pExpr->op2 = pDef->funcFlags & OPFLAG_BYTELENARG;
           }
         }
 
-        sqlite3ExprCodeExprList(pParse, pFarg, r1, 0,
-                                SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR);
+        sqlite3ExprCodeExprList(pParse, pFarg, r1, 0, SQLITE_ECEL_FACTOR);
       }else{
         r1 = 0;
       }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       /* Possibly overload the function if the first argument is

Index: src/json.c
==================================================================
--- src/json.c
+++ src/json.c
@@ -499,11 +499,12 @@
 
 /* Make the JSON in p the result of the SQL function.
 */
 static void jsonResult(JsonString *p){
   if( p->bErr==0 ){
-    sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed, 
+    jsonAppendChar(p, 0);
+    sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed-1,
                           p->bStatic ? SQLITE_TRANSIENT : sqlite3_free,
                           SQLITE_UTF8);
     jsonZero(p);
   }
   assert( p->bStatic );

Index: src/util.c
==================================================================
--- src/util.c
+++ src/util.c
@@ -844,11 +844,13 @@
     if( z[k]!=0 ) return 1;
     return 0;
   }else
 #endif /* SQLITE_OMIT_HEX_INTEGER */
   {
-    return sqlite3Atoi64(z, pOut, sqlite3Strlen30(z), SQLITE_UTF8);
+    int n = (int)(0x3fffffff&strspn(z,"+- \n\t0123456789"));
+    if( z[n] ) n++;
+    return sqlite3Atoi64(z, pOut, n, SQLITE_UTF8);
   }
 }
 
 /*
 ** If zNum represents an integer that will fit in 32-bits, then set

Index: src/vdbe.c
==================================================================
--- src/vdbe.c
+++ src/vdbe.c
@@ -554,10 +554,13 @@
     for(j=0; j<25 && j<pMem->n; j++){
       c = pMem->z[j];
       sqlite3_str_appendchar(pStr, 1, (c>=0x20&&c<=0x7f) ? c : '.');
     }
     sqlite3_str_appendf(pStr, "]%s", encnames[pMem->enc]);
+    if( f & MEM_Term ){
+      sqlite3_str_appendf(pStr, "(0-term)");
+    }
   }
 }
 #endif
 
 #ifdef SQLITE_DEBUG
@@ -3083,10 +3086,13 @@
     }else{
       if( len>db->aLimit[SQLITE_LIMIT_LENGTH] ) goto too_big;
       rc = sqlite3VdbeMemFromBtree(pC->uc.pCursor, aOffset[p2], len, pDest);
       if( rc!=SQLITE_OK ) goto abort_due_to_error;
       sqlite3VdbeSerialGet((const u8*)pDest->z, t, pDest);
+      if( (t&1)!=0 && encoding==SQLITE_UTF8 ){
+        pDest->flags |= MEM_Term;
+      }
       pDest->flags &= ~MEM_Ephem;
     }
   }
 
 op_column_out:

Index: src/vdbeInt.h
==================================================================
--- src/vdbeInt.h
+++ src/vdbeInt.h
@@ -609,10 +609,11 @@
 #endif
 #ifdef SQLITE_DEBUG
 int sqlite3VdbeMemIsRowSet(const Mem*);
 #endif
 int sqlite3VdbeMemSetRowSet(Mem*);
+void sqlite3VdbeMemZeroTerminateIfAble(Mem*);
 int sqlite3VdbeMemMakeWriteable(Mem*);
 int sqlite3VdbeMemStringify(Mem*, u8, u8);
 int sqlite3IntFloatCompare(i64,double);
 i64 sqlite3VdbeIntValue(const Mem*);
 int sqlite3VdbeMemIntegerify(Mem*);

Index: src/vdbeapi.c
==================================================================
--- src/vdbeapi.c
+++ src/vdbeapi.c
@@ -512,10 +512,11 @@
   }
   if( n>0x7fffffff ){
     (void)invokeValueDestructor(z, xDel, pCtx);
   }else{
     setResultStrOrError(pCtx, z, (int)n, enc, xDel);
+    sqlite3VdbeMemZeroTerminateIfAble(pCtx->pOut);
   }
 }
 #ifndef SQLITE_OMIT_UTF16
 void sqlite3_result_text16(
   sqlite3_context *pCtx,

Index: src/vdbemem.c
==================================================================
--- src/vdbemem.c
+++ src/vdbemem.c
@@ -311,10 +311,36 @@
   assert( (pMem->flags & MEM_Dyn)==0 );
   pMem->z = pMem->zMalloc;
   pMem->flags &= (MEM_Null|MEM_Int|MEM_Real|MEM_IntReal);
   return SQLITE_OK;
 }
+
+/*
+** If pMem is already a string, detect if it is a zero-terminated
+** string, or make it into one if possible, and mark it as such.
+**
+** This is an optimization.  Correct operation continues even if
+** this routine is a no-op.
+*/
+void sqlite3VdbeMemZeroTerminateIfAble(Mem *pMem){
+  if( (pMem->flags & (MEM_Str|MEM_Term))!=MEM_Str ) return;
+  if( pMem->enc!=SQLITE_UTF8 ) return;
+  if( NEVER(pMem->z==0) ) return;
+  if( pMem->flags & MEM_Dyn ){
+    if( pMem->xDel==sqlite3_free
+     && sqlite3_msize(pMem->z) >= (u64)(pMem->n+1)
+     && pMem->z[pMem->n]==0 
+    ){
+      pMem->flags |= MEM_Term;
+      return;
+    }
+  }else if( pMem->szMalloc>0 && pMem->szMalloc >= pMem->n+1 ){
+    pMem->z[pMem->n] = 0;
+    pMem->flags |= MEM_Term;
+    return;
+  }
+}
 
 /*
 ** It is already known that pMem contains an unterminated string.
 ** Add the zero terminator.
 **
@@ -801,18 +827,21 @@
     case SQLITE_AFF_REAL: {
       sqlite3VdbeMemRealify(pMem);
       break;
     }
     default: {
+      int rc;
       assert( aff==SQLITE_AFF_TEXT );
       assert( MEM_Str==(MEM_Blob>>3) );
       pMem->flags |= (pMem->flags&MEM_Blob)>>3;
       sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
       assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
       pMem->flags &= ~(MEM_Int|MEM_Real|MEM_IntReal|MEM_Blob|MEM_Zero);
       if( encoding!=SQLITE_UTF8 ) pMem->n &= ~1;
-      return sqlite3VdbeChangeEncoding(pMem, encoding);
+      rc = sqlite3VdbeChangeEncoding(pMem, encoding);
+      if( rc ) return rc;
+      sqlite3VdbeMemZeroTerminateIfAble(pMem);
     }
   }
   return SQLITE_OK;
 }