linux-kernel - Re: [PATCH v2] Coccinelle: Script to remove unnecessary static on local variables

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Message-ID: <alpine.DEB.2.20.1708010704350.2671@hadrien>
Date:   Tue, 1 Aug 2017 07:04:50 +0200 (CEST)
From:   Julia Lawall <julia.lawall@...6.fr>
To:     "Gustavo A. R. Silva" <gustavo@...eddedor.com>
cc:     Julia Lawall <Julia.Lawall@...6.fr>,
        Gilles Muller <Gilles.Muller@...6.fr>,
        Nicolas Palix <nicolas.palix@...g.fr>,
        Michal Marek <mmarek@...e.com>, cocci@...teme.lip6.fr,
        linux-kernel@...r.kernel.org, Pavel Machek <pavel@....cz>,
        Borislav Petkov <bp@...en8.de>,
        Peter Senna Tschudin <peter.senna@...il.com>
Subject: Re: [PATCH v2] Coccinelle: Script to remove unnecessary static on
 local variables

Acked-by: Julia Lawall <julia.lawall@...6.fr>

On Mon, 31 Jul 2017, Gustavo A. R. Silva wrote:

> Coccinelle script to remove unnecessary static on local variables when
> the variables are not used before update.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@...eddedor.com>
> ---
> Changes in v2:
>  Update header and Copyright note.
>
>  scripts/coccinelle/misc/static_unnecessary.cocci | 96 ++++++++++++++++++++++++
>  1 file changed, 96 insertions(+)
>  create mode 100644 scripts/coccinelle/misc/static_unnecessary.cocci
>
> diff --git a/scripts/coccinelle/misc/static_unnecessary.cocci b/scripts/coccinelle/misc/static_unnecessary.cocci
> new file mode 100644
> index 0000000..2b10586
> --- /dev/null
> +++ b/scripts/coccinelle/misc/static_unnecessary.cocci
> @@ -0,0 +1,96 @@
> +/// Drop static on local variable when the variable is not used before update.
> +//#
> +//# Removing unnecessary static on local variables reduces the code
> +//# size and increases maintainability.
> +//#
> +//# On the other hand, even though it is rare, be aware that if a
> +//# large object is initialized all at once, it might not be wise
> +//# to remove the static because that would increase the risk of a
> +//# stack overflow.
> +///
> +// Confidence: Moderate
> +// Copyright: (C) 2017 Julia Lawall, Inria. GPLv2.
> +// URL: http://coccinelle.lip6.fr/
> +// Copyright: (C) 2017 Gustavo A. R. Silva. GPLv2.
> +// Work supported by a grant from
> +// The Linux Foundation's Core Infrastructure Initiative.
> +// URL: https://www.coreinfrastructure.org/
> +// Options: --no-includes --include-headers
> +// Keywords: static
> +
> +virtual patch
> +virtual context
> +virtual org
> +virtual report
> +
> +// <smpl>
> +@bad exists@
> +position p;
> +identifier x;
> +expression e;
> +type T;
> +@@
> +
> +T x@p;
> +... when != x = e
> +x = <+...x...+>
> +
> +@...se exists@
> +position p;
> +identifier x;
> +type T;
> +@@
> +
> +T x@p;
> +...
> + &x
> +
> +@...ify depends on patch && !context && !org && !report@
> +identifier x;
> +expression e;
> +type T;
> +position p != {bad.p,worse.p};
> +@@
> +
> +-static
> + T x@p;
> + ... when != x
> +     when strict
> +?x = e;
> +// </smpl>
> +
> +
> +// ----------------------------------------------------------------------------
> +
> +@...ify_context depends on !patch && (context || org || report) forall@
> +type T;
> +identifier x;
> +expression e;
> +position p != {bad.p,worse.p};
> +position j0;
> +@@
> +
> +* static
> + T x@j0@p;
> + ... when != x
> +     when strict
> +?x = e;
> +
> +// ----------------------------------------------------------------------------
> +
> +@...ipt:python modify_org depends on org@
> +j0 << modify_context.j0;
> +@@
> +
> +msg = "Unnecessary static on local variable."
> +coccilib.org.print_todo(j0[0], msg)
> +
> +// ----------------------------------------------------------------------------
> +
> +@...ipt:python modify_report depends on report@
> +j0 << modify_context.j0;
> +@@
> +
> +msg = "Unnecessary static on local variable."
> +coccilib.report.print_report(j0[0], msg)
> +
> --
> 2.5.0
>
>