[Mesa-dev] [PATCH v2] docs: add documentation for building with meson

Wed Oct 18 22:27:39 UTC 2017

On Wednesday, 2017-10-18 18:09:22 +0000, Dylan Baker wrote:
> v2: - Add information about CC, CXX, CFLAGS, and CXXFLAGS (Nicolai)
>     - Add message at top that meson for mesa is still a work in progress
>     - Add trailing "/" to directories (Eric E.)
>     - Fix a number of spelling/grammar/style suggestions from Eric E.
>     - Make a number of changes as suggested by Emil.
> 
> Signed-off-by: Dylan Baker <dylanx.c.baker at intel.com>
> ---
>  docs/contents.html |   1 +
>  docs/meson.html    | 126 +++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 127 insertions(+)
>  create mode 100644 docs/meson.html
> 
> diff --git a/docs/contents.html b/docs/contents.html
> index d5455421091..9a86019e2f6 100644
> --- a/docs/contents.html
> +++ b/docs/contents.html
> @@ -43,6 +43,7 @@
>  <li><a href="install.html" target="_parent">Compiling / Installing</a>
>    <ul>
>      <li><a href="autoconf.html" target="_parent">Autoconf</a></li>
> +    <li><a href="meson.html" target="_parent">Meson</a></li>
>    </ul>
>  </li>
>  <li><a href="precompiled.html" target="_parent">Precompiled Libraries</a>
> diff --git a/docs/meson.html b/docs/meson.html
> new file mode 100644
> index 00000000000..9f933382965
> --- /dev/null
> +++ b/docs/meson.html
> @@ -0,0 +1,126 @@
> +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
> +<html lang="en">
> +<head>
> +  <meta http-equiv="content-type" content="text/html; charset=utf-8">
> +  <title>Compilation and Installation using Meson</title>
> +  <link rel="stylesheet" type="text/css" href="mesa.css">
> +</head>
> +<body>
> +
> +<div class="header">
> +  <h1>The Mesa 3D Graphics Library</h1>
> +</div>
> +
> +<iframe src="contents.html"></iframe>
> +<div class="content">
> +
> +<h1>Compilation and Installation using Meson</h1>
> +
> +<h2 id="basic">1. Basic Usage</h2>
> +
> +<p><strong>The Meson build system for Mesa is still under active development,
> +and should not be used in production environments.</strong></p>
> +
> +<p>
> +The meson program is used to configure the source directory and generates
> +either a ninja build file, or Visual Studio® build files. The latter, and must

s/, and//

> +be enabled via the --backend switch, as ninja is always the default. Meson only
> +supports out-of-tree builds, and must be passed a directory to put built and
> +generated sources into. We'll call that directory "build" for examples.
> +</p>
> +
> +<pre>
> +    meson build/
> +</pre>
> +
> +<p>
> +To see a description of your options you can run "meson configure" with no
> +arguments. This will show your meson global arguments and project arguments,
> +along with their defaults and your local settings.
> +</p>
> +
> +<pre>
> +    meson configure build/
> +</pre>
> +
> +<p>
> +With arguments "meson configure" is used to change options on already
> +configured build directory. All options passed to this command are in the form
> +-D"command"="value".

s/command/option/, and I think you can drop the quotes?

> +</p>
> +
> +<pre>
> +    meson configure build/ -Dprefix=/tmp/install -Dglx=true
> +</pre>
> +
> +<p>
> +Once you've run meson successfully you can use your configured backend to build
> +the project. With ninja, the -C option can be be used to point at a directory
> +to build.
> +</p>
> +
> +<pre>
> +    ninja -C build/
> +</pre>
> +
> +<p>
> +Without arguments, it will produce libGL.so and/or several other libraries
> +depending on the options you have chosen. Later, if you want to rebuild for a
> +different configuration, you should run <code>ninja clean</code> before
> +rebuilding, or create a new out of tree build directory (meson supports an
> +unlimited number of them) for each configuration you want to build.
> +</p>
> +
> +<dt><code>CC, CFLAGS, CXX, CXXFLAGS</code></dt>
> +<dd><p>These environment variables
> +control the C and C++ compilers used during the build. The default compilers
> +depends on your operating system. Meson supports most of the popular compilers,
> +a complete list is available
> +<a href="http://mesonbuild.com/Reference-tables.html#compiler-ids">here</a>.
> +
> +These arguments are consumed and stored by meson when it is initialized or
> +re-initialized. Therefore passing them to meson configure will not do anything,
> +and passing them to ninja will only do something if ninja decides to
> +re-initialze meson, for example, if a meson.build file has been changed.
> +Changing these variables will not cause all targets to be rebuilt, so running
> +ninja clean is recomended when changing any of these variables.
> +</p>
> +
> +<pre>
> +    CC=clang CXX=clang++ meson build-clang
> +    ninja -C build-clang
> +
> +    touch meson.build
> +    ninja -C build-clang clean
> +    CFLAGS=-Wno-typedef-redefinition ninja -C build-clang

`touch` should be after `clean`, otherwise `clean` will execute the
regeneration, and the CFLAGS will come too late.

Do you want to also mention Lyude's question about using a non-standard
llvm-config here? It was surprisingly trivial to do :)

Other than that, this v2 is:
Reviewed-by: Eric Engestrom <eric at engestrom.ch>

> +</dd>
> +
> +<dt><code>PKG_CONFIG_PATH</code></dt>
> +<dd><p>The
> +<code>pkg-config</code> utility is a hard requirement for configuring and
> +building Mesa on Linux and BSD. It is used to search for external libraries
> +on the system. This environment variable is used to control the search
> +path for <code>pkg-config</code>. For instance, setting
> +<code>PKG_CONFIG_PATH=/usr/X11R6/lib/pkgconfig</code> will search for
> +package metadata in <code>/usr/X11R6</code> before the standard
> +directories.</p>
> +</dd>
> +</dl>
> +
> +<p>
> +One of the oddities of meson is that some options are different when passed to
> +the <code>meson</code> than to <code>meson configure</code>. These options are
> +passed as --option=foo to <code>meson</code>, but -Doption=foo to <code>meson
> +configure</code>. Mesa defined options are always passed as -Doption=foo.
> +<p>
> +
> +<p>For those coming from autotools be aware of the following:</p>
> +
> +<dl>
> +<dt><code>--buildtype/-Dbuildtype</code></dt>
> +<dd><p>This option will set the compiler debug/optimisation levels (if the user
> +hasn't already set them via the CFLAGS/CXXFLAGS) and macros to aid in
> +debugging the Mesa libraries.</p>
> +
> +<p>Note that in meson this defaults to "debug", and  not setting it to
> +"release" will yield non-optimal performance and binary size</p>
> -- 
> 2.14.2
> 