Update documentation about external toolchain

Reword the documentation on external toolchain to take into account
the new features added since 2010.11 concerning external toolchain
profiles.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
This commit is contained in:
Thomas Petazzoni 2011-01-30 15:37:46 +01:00 committed by Peter Korsgaard
parent 43d7e91f28
commit 7af45b8ae0

View File

@ -706,31 +706,48 @@ $(ZLIB_DIR)/libz.a: $(ZLIB_DIR)/.configured
</ul> </ul>
<p>Buildroot supports using existing toolchains through a <p>Buildroot supports using existing toolchains through a
mechanism called <i>external toolchain</i>.</p> mechanism called <i>external toolchain</i>. The external toolchain
mechanism is enabled in the <code>Toolchain</code> menu, by
selecting <code>External toolchain</code> in <code>Toolchain
type</code>.</p>
<p>To enable the use of an external toolchain, go to the <p>Then, you have three solutions to use an external
<code>Toolchain</code> menu, and :</p> toolchain:</p>
<ul> <ul>
<li>Select the <code>External binary toolchain</code> toolchain
type</li> <li>Use a predefined external toolchain profile, and let
<li>Select the appropriate <code>External toolchain C Buildroot download, extract and install the toolchain. Buildroot
library</code></li> already knows about a few CodeSourcery toolchains for ARM,
<li>Select the appropriate values for <code>Enable large PowerPC, MIPS and SuperH. Just select the toolchain profile
file</code>, <code>Enable IPv6</code>, <code>Enable in <code>Toolchain</code> through the available ones. This is
RPC</code>, <code>Enable toolchain definitely the easiest solution.</li>
locale/i18n</code>, <code>Enable WCHAR</code>, <code>Enable
program invocation</code>, <code>Build/install c++ compiler and <li>Use a predefined external toolchain profile, but instead of
libstdc++</code>, according to the configuration of your having Buildroot download and extract the toolchain, you can
external toolchain. Buildroot will check those values at the tell Buildroot where your toolchain is already installed on your
beginning of the compilation process and will tell you if you system. Just select the toolchain profile
used incorrect values.</li> in <code>Toolchain</code> through the available ones,
<li>Adjust the <code>External toolchain path</code> unselect <code>Download toolchain automatically</code>, and fill
appropriately. It should be set to a path where a bin/ directory the <code>Toolchain path</code> text entry with the path to your
contains your cross-compiling tools</li> cross-compiling toolchain.</li>
<li>Adjust the <code>External toolchain prefix</code> so that the
prefix, suffixed with <code>-gcc</code> or <code>-ld</code> will <li>Use a completely custom external toolchain. This is
correspond to your cross-compiling tools</li> particularly useful for toolchains generated using
Crosstool-NG. To do this, select the <code>Custom
toolchain</code> solution in the <code>Toolchain</code>
list. You need to fill the <code>Toolchain
path</code>, <code>Toolchain prefix</code> and <code>External
toolchain C library</code> options. Then, you have to tell
Buildroot what your external toolchain supports. If your
external toolchain uses the <i>glibc</i> library, you only have
to tell whether your toolchain supports C++ or not. If your
external toolchain uses the <i>uclibc</i> library, then you have
to tell Buildroot if it supports largefile, IPv6, RPC,
wide-char, locale, program invocation, threads and C++. At the
beginning of the execution, Buildroot will tell you if the
selected options do not match the toolchain configuration.</li>
</ul> </ul>
<p>Our external toolchain support has been tested with toolchains <p>Our external toolchain support has been tested with toolchains