php: 不能嵌套try-catch-fnally,否则执行时间过长

php不能try-catch-fnally里面在嵌套try-catch-fnall，否则本来执行时间不长的程序，会被执行更长时间，这是php的bug吗？

如：

      try{
          代码块
        }catch (Exception $e)
        {
            echo get_class($e), ": ", $e->getMessage(), "
";
            echo " File=", $e->getFile(), "
";
            echo " Line=", $e->getLine(), "
";
            echo $e->getTraceAsString();
        }finally{
           try{
             代码块
           }catch (Exception $e)
           {
            echo get_class($e), ": ", $e->getMessage(), "
";
            echo " File=", $e->getFile(), "
";
            echo " Line=", $e->getLine(), "
";
            echo $e->getTraceAsString();
           }finally{
              代码块
           }
        }

　　应该改成：

         try{
             代码块
           }catch (Exception $e)
           {
            echo get_class($e), ": ", $e->getMessage(), "
";
            echo " File=", $e->getFile(), "
";
            echo " Line=", $e->getLine(), "
";
            echo $e->getTraceAsString();
           }finally{
              代码块
           }

            try{
             代码块
           }catch (Exception $e)
           {
            echo get_class($e), ": ", $e->getMessage(), "
";
            echo " File=", $e->getFile(), "
";
            echo " Line=", $e->getLine(), "
";
            echo $e->getTraceAsString();
           }finally{
              代码块
           }