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Reply-To: Luis Machado <lgustavo@codesourcery.com>
Subject: Re: [PATCH 1/6] New function null_stream
References: <1484051178-16013-1-git-send-email-yao.qi@linaro.org> <1484560977-8693-1-git-send-email-yao.qi@linaro.org> <1484560977-8693-2-git-send-email-yao.qi@linaro.org> <e8c35379-2b5e-eaa2-8c46-89cf63ef3670@codesourcery.com> <20170118144506.GM28060@E107787-LIN>
To: Yao Qi <qiyaoltc@gmail.com>
CC: <gdb-patches@sourceware.org>
From: Luis Machado <lgustavo@codesourcery.com>
Message-ID: <79d15965-fd1c-5cff-54f1-d6b7d2e6b884@codesourcery.com>
Date: Wed, 18 Jan 2017 14:53:00 -0000
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On 01/18/2017 08:45 AM, Yao Qi wrote:
> On 17-01-17 07:49:07, Luis Machado wrote:
>>>
>>> +struct ui_file *
>>> +null_stream (void)
>>> +{
>>> +  static struct ui_file *stream = NULL;
>>> +
>>> +  if (stream == NULL)
>>> +    {
>>> +      stream = ui_file_new ();
>>> +      make_final_cleanup (do_ui_file_delete, stream);
>>> +    }
>>
>> Since we're explicitly setting stream to NULL, we will always
>> execute the conditional block, so it is not needed. Unless this is
>> supposed to reuse a stream, but in that case the code would be
>> incorrect.
>>
>
> It is a reused null stream.  Different parts of gdb can use it.  Why
> is it incorrect?
>

We're setting stream to NULL at the top of the function and then 
checking if it is NULL (it obviously is) right after that? Am i missing 
something?