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From:   Alexander Potapenko <glider@google.com>
Date:   Fri, 3 Mar 2023 21:53:46 +0100
Message-ID: <CAG_fn=XDzM_+nXpypPFG95r7EKRWhPGd7C=JZOy7kYrpcC+XDQ@mail.gmail.com>
Subject: Re: Infinite loop in checkpatch.pl
To:     Joe Perches <joe@perches.com>
Cc:     apw@canonical.com, dwaipayanray1@gmail.com,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>
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On Fri, Mar 3, 2023 at 5:53=E2=80=AFPM Joe Perches <joe@perches.com> wrote:
>
> On Fri, 2023-03-03 at 15:28 +0100, Alexander Potapenko wrote:
> > Hi folks,
> >
> > I've noticed that checkpatch.pl chokes on the following file (also atta=
ched):
> >
> > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> > $ cat test-checkpatch.txt
> > diff --git a/mm/kmsan/kmsan_test.c b/mm/kmsan/kmsan_test.c
> > @@ -504,6 +504,25 @@ static void
> > test_memcpy_aligned_to_unaligned2(struct kunit *test)
> > + EXPECTATION_NO_REPORT(expect);                              \
> > + volatile uint##size##_t uninit;                             \
>
> checkpatch isn't a syntax complete c parser.  Don't expect to be.

That's understandable, and I sure don't. But as a user I expect it to
not loop infinitely, and I think that's also reasonable.
The example I gave is not a randomly generated code snippet, but an
excerpt from a valid patch that I sent earlier today:
https://lore.kernel.org/lkml/20230303141433.3422671-4-glider@google.com/,
which checkpatch cannot process.


--=20
Alexander Potapenko
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