Index: src/vdbeaux.c
==================================================================
--- src/vdbeaux.c
+++ src/vdbeaux.c
@@ -2931,14 +2931,15 @@
       swapMixedEndianFloat(v);
     }else{
       v = pMem->u.i;
     }
     len = i = sqlite3VdbeSerialTypeLen(serial_type);
-    while( i-- ){
-      buf[i] = (u8)(v&0xFF);
+    assert( i>0 );
+    do{
+      buf[--i] = (u8)(v&0xFF);
       v >>= 8;
-    }
+    }while( i );
     return len;
   }
 
   /* String or blob */
   if( serial_type>=12 ){