diff --git a/trunk/renge/renge.c b/trunk/renge/renge.c
index a6371b4..c55a503 100644
--- a/trunk/renge/renge.c
+++ b/trunk/renge/renge.c
@@ -184,21 +184,29 @@ static u8 lock = 0;
 static void renge_task_immed_del(){
   u8 i,j;
 
-  // 指定タスクの削除と、リスト前詰め
-  for( i = j = 0; j < IMMED_RSV_TASKS_NUM-1; )
+  // リスト前詰め
+  i = 0;
+  j = 1;
+  while( j < IMMED_RSV_TASKS_NUM )
   {
       if( tasks_immed[ i ] == (void *)0 )
       {
-          tasks_immed[ i ] = tasks_immed[ ++j ];
-          tasks_immed[ j ] = (void *)0;
+          if( tasks_immed[ j ] != (void *)0 )
+          {
+              tasks_immed[ i ] = tasks_immed[ j ];
+              tasks_immed[ j ] = (void *)0;
+              i += 1;
+          }
+      }
+      else
+      {
+          i += 1;
       }
-      i += 1;
       j += 1;
   }
 }
 
 
-
 /**************************************
  **************************************/
 err renge_task_immed_run(){