linux-kernel - Re: [PATCH RESEND] selftests: Suppress unused variable warning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4d625aaf-5c8c-4097-897e-a6ebb469c183@linuxfoundation.org>
Date: Thu, 19 Jun 2025 15:43:40 -0600
From: Shuah Khan <skhan@...uxfoundation.org>
To: John Hubbard <jhubbard@...dia.com>,
 Chen Linxuan <chenlinxuan@...ontech.com>
Cc: Shuah Khan <shuah@...nel.org>, Christian Brauner <brauner@...nel.org>,
 Amir Goldstein <amir73il@...il.com>, Miklos Szeredi <mszeredi@...hat.com>,
 Jan Kara <jack@...e.cz>, zhanjun@...ontech.com, niecheng1@...ontech.com,
 linux-kselftest@...r.kernel.org, linux-kernel@...r.kernel.org,
 Shuah Khan <skhan@...uxfoundation.org>
Subject: Re: [PATCH RESEND] selftests: Suppress unused variable warning

On 6/19/25 15:40, Shuah Khan wrote:
> On 6/19/25 13:00, John Hubbard wrote:
>> On 6/19/25 10:00 AM, Shuah Khan wrote:
>>> On 6/19/25 01:46, Chen Linxuan wrote:
>>>> On Thu, Jun 19, 2025 at 5:23 AM Shuah Khan <skhan@...uxfoundation.org> wrote:
>>>>> On 6/9/25 20:07, Chen Linxuan wrote:
>> ...
>>>>>> diff --git a/tools/testing/selftests/filesystems/mount-notify/mount- notify_test.c b/tools/testing/selftests/filesystems/mount-notify/ mount-notify_test.c
>>>>>> index 63ce708d93ed0..34afe27b7978f 100644
>>>>>> --- a/tools/testing/selftests/filesystems/mount-notify/mount- notify_test.c
>>>>>> +++ b/tools/testing/selftests/filesystems/mount-notify/mount- notify_test.c
>>>>>> @@ -465,7 +465,9 @@ TEST_F(fanotify, rmdir)
>>>>>>        ASSERT_GE(ret, 0);
>>>>>>
>>>>>>        if (ret == 0) {
>>>>>> -             chdir("/");
>>>>>> +             // Suppress -Wunused-result
>>>>>> +             // Ref: https://gcc.gnu.org/bugzilla/show_bug.cgi? id=66425#c34
>>>>>> +             (void) !chdir("/");
>>
>> This is quite ugly. :)
>>
>>>>>>> Why not fix the problem the right way by checking the return value.
>>>>> Suppressing the error isn't useful.
>>>>
>>>> The code is already handling cleanup in error cases,
>>>> and I don't think checking the result of chdir would be useful here.
>>>
>>
>> Why not just fail with the appropriate test result, if chdir() fails
>> here, instead of making a bit of a mess with odd void casts to a
>> negated return value, and a reference to a compiler bug report?
>>
>> Really, Shuah is putting you on the right path here.
> 
> Ha. I didn't ask to suppress the error with the cast. I asked
> to check the return and fail.
> 
>>

Sorry John. I didn't read it correctly the first time.
I probably go get more coffee. :)

thanks,
-- Shuah