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From:   Jonathan Corbet <corbet@lwn.net>
To:     Akira Yokosawa <akiyks@gmail.com>
Cc:     linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] docs: pdfdocs: Adjust \headheight for fancyhdr
In-Reply-To: <c5a5577e-5de8-9cd4-9253-956ccc748417@gmail.com>
References: <c5a5577e-5de8-9cd4-9253-956ccc748417@gmail.com>
Date:   Tue, 12 Oct 2021 14:09:15 -0600
Message-ID: <87wnmit384.fsf@meer.lwn.net>
MIME-Version: 1.0
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Akira Yokosawa <akiyks@gmail.com> writes:

> Fancyhdr prior to v4.0 outputs a message per document as follows:
>
>     Package Fancyhdr Warning: \headheight is too small (12.0pt):
>     Make it at least 13.59999pt.
>     We now make it that large for the rest of the document.
>     This may cause the page layout to be inconsistent, however.
>
> Fancyhdr v4.0 complains (once a page!) as follows:
>
>     Package fancyhdr Warning: \headheight is too small (12.0pt):
>     (fancyhdr)    Make it at least 13.59999pt, for example:
>     (fancyhdr)    \setlength{\headheight}{13.59999pt}.
>     (fancyhdr)    You might also make \topmargin smaller to compensate:
>
>     (fancyhdr)    \addtolength{\topmargin}{-1.59999pt}.
>
> Related item in fancyhdr v4.0 announcement on 2021-01-04 [1]:
>
>     Backward incompatible changes:
>       - Eliminate adjustments of \headheight or \footskip, when the
>         header or footer is too high.
>
> [1]: https://www.ctan.org/ctan-ann/id/mailman.2685.1609863692.2532.ctan-ann@ctan.org
>
> Silence the warnings by adding a couple of \addtolength commands in
> the preamble.
>
> Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
> ---
> Hi,
>
> This update doesn't have much visual effects in the final PDFs
> (adjustment of only 1.6pt), but getting rid of harmless warnings
> would help spot potential important ones.
>
> Tested against Sphinx versions 2.4.4 and 4.2.0, with Tex Live
> versions 2017/debian (Ubuntu 18.04), 2019/debian (Ubuntu 20.04),
> and vanilla 2021 (as of 2021-10-08).
>
>         Thanks, Akira
> --
>  Documentation/conf.py | 3 +++
>  1 file changed, 3 insertions(+)

Applied, thanks.

jon