1. Install git ,
   to conveniently download the OpenWrt source code, and build
tools to do the cross-compilation process:

   apt-get update
   
   sudo apt-get install git-core build-essential libssl-dev libncurses5-dev unzip

   Some feeds might not available over git but only via subversion (short: svn)
   or mercurial.
   If you want to obtain their source-code, you need to install svn and mercurial as well:

   sudo apt-get install subversion mercurial

   • for information about the build tools see make and build-essential
   • for information about git see git(7)
   • for information about the subversion tool see svn and subversion
     documentation (multiple languages)
2. Download the OpenWrt bleeding edge(trunk Version) with git (see Downloading
   Sources for more options!):

   git clone git:git.openwrt.org/openwrt.git

   this creates a directory 'openwrt', which is the OpenWrt Buildroot build-directory 
   
   the OpenWrt toolchain "OpenWrt Buildroot" is included

3. (optional) Download and install all available "feeds" (see OpenWrt
   Feeds for more options!):

   cd openwrt && ./scripts/feeds update -a && ./scripts/feeds install -a

4. Make OpenWrt Buildroot check for missing packages on your build-system using one of the following commands:

   make defconfig
   
   make prereq
   
   make menuconfig

   There you will need to select what you want to compile.

5. Proceed with build (i.e.
   cross-compile the downloaded sources to binaries)

   After the cross-compilation process the ''trunk''-directory contained 244,451 files with a total size of 3.2GiB!

其它版本号地址:http://git.openwrt.org/

dl文件夹下载:http://downloads.openwrt.org.cn/sources/

我在第一次编译OpenWRT时，出现例如以下错误提示：

gconvert.c:66:2: error: #error GNU libiconv not in use but included iconv.h is from libiconv

我在网上找解决方式，结果一致地都是说，又一次 ./configure 一下：

./configure --enable-iconv=no --with-libiconv=gnu

make

可问题的关键是：OpenWRT的trunk路径下没见有个 configure 呀！

后来，经过细致推敲，发现是在编glib时没通过。

$ find -name "gconvert.c"

./build_dir/host/pkg-config-0.28/glib/glib/gconvert.c

那我就直接进到 ./build_dir/host/pkg-config-0.28/glib/ 路径下。发现该路径下有 configure 文件。

那我说直接在该路径下编译 glib

$ cd build_dir/host/pkg-config-0.28/glib/

./configure --enable-iconv=no --with-libiconv=gnu

make

这样。glib 就顺利通过了编译。

再回到 OpenWRT的trunk路径下，继续 make.