From: "David Hildenbrand (Red Hat)" <david@kernel.org>
To: Ankit Khushwaha <ankitkhushwaha.linux@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
"Liam R. Howlett" <Liam.Howlett@oracle.com>,
Vlastimil Babka <vbabka@suse.cz>, Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Michal Hocko <mhocko@suse.com>, Shuah Khan <shuah@kernel.org>,
linux-mm@kvack.org, linux-kselftest@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] selftest/mm: fix pointer comparison in mremap_test
Date: Fri, 7 Nov 2025 10:27:27 +0100 [thread overview]
Message-ID: <6e07949b-d86f-46d8-a68c-9717cfb26084@kernel.org> (raw)
In-Reply-To: <aQyOZ6eYng-IjxS_@fedora>
On 06.11.25 13:02, Ankit Khushwaha wrote:
> On Thu, Nov 06, 2025 at 12:18:57PM +0100, David Hildenbrand (Red Hat) wrote:
>> On 06.11.25 11:49, Ankit Khushwaha wrote:
>>> Pointer arthemitic with 'void * addr' and 'unsigned long long dest_alignment'
>>> triggers following warning:
>>>
>>> mremap_test.c:1035:31: warning: pointer comparison always evaluates to
>>> false [-Wtautological-compare]
>>> 1035 | if (addr + c.dest_alignment < addr) {
>>> | ^
>>>
>>> typecasting 'addr' to 'unsigned long long' to fix pointer comparison.
>>
>> With which compiler are you seeing this?
>
> Hi David,
>
> clang version 20.1.8 (Fedora 20.1.8-4.fc42) raised this warning.
>
> To reproduce:
> make -C tools/testing/selftests/mm CC=clang
Thanks, and thanks to Lorenzo for the details.
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
--
Cheers
David
next prev parent reply other threads:[~2025-11-07 9:27 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-06 10:49 [PATCH] selftest/mm: fix pointer comparison in mremap_test Ankit Khushwaha
2025-11-06 11:18 ` David Hildenbrand (Red Hat)
2025-11-06 12:02 ` Ankit Khushwaha
2025-11-06 14:26 ` Lorenzo Stoakes
2025-11-07 9:27 ` David Hildenbrand (Red Hat) [this message]
2025-11-08 0:08 ` Andrew Morton
2025-11-08 16:03 ` Ankit Khushwaha
2025-11-09 6:54 ` Mike Rapoport
2025-11-09 19:11 ` Vlastimil Babka
2025-11-10 21:43 ` Nathan Chancellor
2025-11-06 14:40 ` Lorenzo Stoakes
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6e07949b-d86f-46d8-a68c-9717cfb26084@kernel.org \
--to=david@kernel.org \
--cc=Liam.Howlett@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=ankitkhushwaha.linux@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lorenzo.stoakes@oracle.com \
--cc=mhocko@suse.com \
--cc=rppt@kernel.org \
--cc=shuah@kernel.org \
--cc=surenb@google.com \
--cc=vbabka@suse.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).