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  <title>Compilation and Installation using Autoconf</title>
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  <h1>The Mesa 3D Graphics Library</h1>
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<h1>Compilation and Installation using Autoconf</h1>

<ol>
<li><p><a href="#basic">Basic Usage</a></li>
<li><p><a href="#driver">Driver Options</a>
  <ul>
  <li><a href="#xlib">Xlib Driver Options</a></li>
  <li><a href="#dri">DRI Driver Options</a></li>
  <li><a href="#osmesa">OSMesa Driver Options</a></li>
  </ul>
</ol>


<h2 id="basic">1. Basic Usage</h2>

<p>
The autoconf generated configure script can be used to guess your
platform and change various options for building Mesa. To use the
configure script, type:
</p>

<pre>
    ./configure
</pre>

<p>
To see a short description of all the options, type <code>./configure
--help</code>. If you are using a development snapshot and the configure
script does not exist, type <code>./autogen.sh</code> to generate it
first. If you know the options you want to pass to
<code>configure</code>, you can pass them to <code>autogen.sh</code>. It
will run <code>configure</code> with these options after it is
generated. Once you have run <code>configure</code> and set the options
to your preference, type:
</p>

<pre>
    make
</pre>

<p>
This will produce libGL.so and several other libraries depending on the
options you have chosen. Later, if you want to rebuild for a different
configuration run <code>make realclean</code> before rebuilding.
</p>

<p>
Some of the generic autoconf options are used with Mesa:
</p>
<dl>
<dt><code>--prefix=PREFIX</code></dt>
<dd><p>This is the root directory where
files will be installed by <code>make install</code>. The default is
<code>/usr/local</code>.</p>
</dd>

<dt><code>--exec-prefix=EPREFIX</code></dt>
<dd><p>This is the root directory
where architecture-dependent files will be installed. In Mesa, this is
only used to derive the directory for the libraries. The default is
<code>${prefix}</code>.</p>
</dd>

<dt><code>--libdir=LIBDIR</code></dt>
<dd><p>This option specifies the directory
where the GL libraries will be installed. The default is
<code>${exec_prefix}/lib</code>. It also serves as the name of the
library staging area in the source tree. For instance, if the option
<code>--libdir=/usr/local/lib64</code> is used, the libraries will be
created in a <code>lib64</code> directory at the top of the Mesa source
tree.</p>
</dd>

<dt><code>--sysconfdir=DIR</code></dt>
<dd><p>This option specifies the directory where the configuration
files will be installed. The default is <code>${prefix}/etc</code>.
Currently there's only one config file provided when dri drivers are
enabled - it's <code>drirc</code>.</p>
</dd>

<dt><code>--enable-static, --disable-shared</code></dt>
<dd><p>By default, Mesa
will build shared libraries. Either of these options will force static
libraries to be built. It is not currently possible to build static and
shared libraries in a single pass.</p>
</dd>

<dt><code>CC, CFLAGS, CXX, CXXFLAGS</code></dt>
<dd><p>These environment variables
control the C and C++ compilers used during the build. By default,
<code>gcc</code> and <code>g++</code> are used and the debug/optimisation
level is left unchanged.</p>
</dd>

<dt><code>LDFLAGS</code></dt>
<dd><p>An environment variable specifying flags to
pass when linking programs. These should be empty and
<code>PKG_CONFIG_PATH</code> is recommended to be used instead. If needed
it can be used to direct the linker to use libraries in nonstandard
directories. For example, <code>LDFLAGS="-L/usr/X11R6/lib"</code>.</p>
</dd>

<dt><code>PKG_CONFIG_PATH</code></dt>
<dd><p>The
<code>pkg-config</code> utility is a hard requirement for cofiguring and
building mesa. 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>
There are also a few general options for altering the Mesa build:
</p>
<dl>
<dt><code>--enable-debug</code></dt>
<dd><p>This option will enable compiler
options and macros to aid in debugging the Mesa libraries.</p>
</dd>

<dt><code>--disable-asm</code></dt>
<dd><p>There are assembly routines
available for a few architectures. These will be used by default if
one of these architectures is detected. This option ensures that
assembly will not be used.</p>
</dd>

<dt><code>--build=</code></dt>
<dt><code>--host=</code></dt>
<dd><p>By default, the build will compile code for the architecture that
it's running on. In order to build cross-compile Mesa on a x86-64 machine
that is to run on a i686, one would need to set the options to:</p>

<p><code>--build=x86_64-pc-linux-gnu --host=i686-pc-linux-gnu</code></p>

Note that these can vary from distribution to distribution. For more
information check with the
<a href="https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/html_node/Specifying-Target-Triplets.html">
autoconf manual</a>.
Note that you will need to correctly set <code>PKG_CONFIG_PATH</code> as well.


<p>In some cases a single compiler is capable of handling both architectures
(multilib) in that case one would need to set the <code>CC,CXX</code> variables
appending the correct machine options. Seek your compiler documentation for
further information -
<a href="https://gcc.gnu.org/onlinedocs/gcc/Submodel-Options.html"> gcc
machine dependent options</a></p>

<p>In addition to specifying correct <code>PKG_CONFIG_PATH</code> for the target
architecture, the following should be sufficient to configure multilib Mesa</p>

<code>./configure CC="gcc -m32" CXX="g++ -m32" --build=x86_64-pc-linux-gnu --host=i686-pc-linux-gnu ...</code>
</dd>
</dl>


<h2 id="driver">2. Driver Options</h2>

<p>
There are several different driver modes that Mesa can use. These are
described in more detail in the <a href="install.html">basic
installation instructions</a>. The Mesa driver is controlled through the
configure options <code>--enable-xlib-glx</code>, <code>--enable-osmesa</code>,
and <code>--enable-dri</code>.
</p>

<h3 id="xlib">Xlib</h3><p>
It uses Xlib as a software renderer to do all rendering. It corresponds
to the option <code>--enable-xlib-glx</code>. The libX11 and libXext
libraries, as well as the X11 development headers, will be need to
support the Xlib driver.

<h3 id="dri">DRI</h3><p>This mode uses the DRI hardware drivers for
accelerated OpenGL rendering. Enable the DRI drivers with the option
<code>--enable-dri</code>. See the <a href="install.html">basic
installation instructions</a> for details on prerequisites for the DRI
drivers.

<!-- DRI specific options -->
<dl>
<dt><code>--with-dri-driverdir=DIR</code>
<dd><p> This option specifies the
location the DRI drivers will be installed to and the location libGL
will search for DRI drivers. The default is <code>${libdir}/dri</code>.
<dt><code>--with-dri-drivers=DRIVER,DRIVER,...</code>
<dd><p> This option
allows a specific set of DRI drivers to be built. For example,
<code>--with-dri-drivers="swrast,i965,radeon,nouveau"</code>. By
default, the drivers will be chosen depending on the target platform.
See the directory <code>src/mesa/drivers/dri</code> in the source tree
for available drivers. Beware that the swrast DRI driver is used by both
libGL and the X.Org xserver GLX module to do software rendering, so you
may run into problems if it is not available.
<!-- This explanation might be totally bogus. Kristian? -->
<dt><code>--disable-driglx-direct</code>
<dd><p> Disable direct rendering in
GLX. Normally, direct hardware rendering through the DRI drivers and
indirect software rendering are enabled in GLX. This option disables
direct rendering entirely. It can be useful on architectures where
kernel DRM modules are not available.
<dt><code>--enable-glx-tls</code> <dd><p>
Enable Thread Local Storage (TLS) in
GLX.
<dt><code>--with-expat=DIR</code>
<dd><p><strong>DEPRECATED</strong>, use <code>PKG_CONFIG_PATH</code> instead.</p>
<p>The DRI-enabled libGL uses expat to
parse the DRI configuration files in <code>${sysconfdir}/drirc</code> and
<code>~/.drirc</code>. This option allows a specific expat installation
to be used. For example, <code>--with-expat=/usr/local</code> will
search for expat headers and libraries in <code>/usr/local/include</code>
and <code>/usr/local/lib</code>, respectively.
</dl>

<h3 id="osmesa">OSMesa </h3><p> No libGL is built in this
mode. Instead, the driver code is built into the Off-Screen Mesa
(OSMesa) library. See the <a href="osmesa.html">Off-Screen Rendering</a>
page for more details.  It corresponds to the option
<code>--enable-osmesa</code>.

<!-- OSMesa specific options -->
<dl>
<dt><code>--with-osmesa-bits=BITS</code>
<dd><p> This option allows the size
of the color channel in bits to be specified. By default, an 8-bit
channel will be used, and the driver will be named libOSMesa. Other
options are 16- and 32-bit color channels, which will add the bit size
to the library name. For example, <code>--with-osmesa-bits=16</code>
will create the libOSMesa16 library with a 16-bit color channel.
</dl>


<h2 id="library">3. Library Options</h2>

<p>
The configure script provides more fine grained control over the GL
libraries that will be built. More details on the specific GL libraries
can be found in the <a href="install.html">basic installation
instructions</a>.

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