Build system setup

1. Assuming a GNU/Linux environment, otherwise see alternative guides.
2. Install Git to download the source code, and your distro's default build tools metapackage to do the cross-compilation process.
3. You may also need to install Subversion (SVN) or Mercurial to fetch the source-code for some feeds which are not available over Git.
4. Install other prerequisite packages, as indicated in the table and examples below.
5. Unset environment variables like SED and GREP_OPTIONS and aliases/functions like which.

This table contains the package name for each build prerequisite in different GNU/Linux and Unix like distributions.

• Bleeding edge distros like Arch Linux may fail to build base-files if Cryptographically signed package lists in Global build settings is enabled.

Note that the advice above may be somewhat outdated. E.g. python3 is currently the default in OpenWrt master, 22.03 and 21.02, while python2.7 has been removed due its end-of-life.

Unfortunately not all dependencies are checked by make config, especially for packages. You may encounter compile errors because you need a specific library in your system, and the only way is to search the missing library from the compiler error log and see what package contains it in your own distro.

The following table is a partial list of such dependencies:

Distribution-specific instructions.

apk add argp-standalone asciidoc bash bc binutils bzip2 cdrkit coreutils \
  diffutils elfutils-dev findutils flex musl-fts-dev g++ gawk gcc gettext git \
  grep gzip intltool libxslt linux-headers make musl-libintl musl-obstack-dev \
  ncurses-dev openssl-dev patch perl python3-dev rsync tar \
  unzip util-linux wget zlib-dev
 
# python2-dev required for OpenWrt 19.07 and earlier is not available on Alpine Linux 3.16 and newer 
 
# missing dependency workaround (libtinfo is not installable by any APK package,
# but can be simulated via libncurses (see: https://stackoverflow.com/a/41517423 )
# w/o this - ERROR: package/boot/uboot-mvebu failed to build (build variant: clearfog)
ln -s /usr/lib/libncurses.so /usr/lib/libtinfo.so 

Arch users may install the openwrt-devel meta-package from the AUR or alternatively, manually install the build dependencies as follows:

# Essential prerequisites
pacman -S --needed base-devel autoconf automake bash binutils bison \
bzip2 fakeroot file findutils flex gawk gcc gettext git grep groff \
gzip libelf libtool libxslt m4 make ncurses openssl patch pkgconf \
python python-distutils-extra rsync sed texinfo time unzip util-linux wget which zlib
 
# Optional prerequisites, depend on the package selection
pacman -S --needed asciidoc help2man intltool perl-extutils-makemaker swig

sudo dnf --setopt install_weak_deps=False --skip-broken install \
bash-completion bzip2 gcc gcc-c++ git make ncurses-devel patch \
rsync tar unzip wget which diffutils python2 python3 perl-base \
perl-Data-Dumper perl-File-Compare perl-File-Copy perl-FindBin \
perl-IPC-Cmd perl-JSON-PP perl-Thread-Queue perl-Time-Piece

Modernized set for Ubuntu 24.04 that has Python 3.12 without python3-distutils: (OpenWrt main/master in Apr 2024)

sudo apt update
sudo apt install build-essential clang flex bison g++ gawk \
gcc-multilib g++-multilib gettext git libncurses5-dev libssl-dev \
python3-setuptools rsync swig unzip zlib1g-dev file wget

set for Ubuntu 22.04 (that has older Python 3.xx):

sudo apt update
sudo apt install build-essential clang flex bison g++ gawk \
gcc-multilib g++-multilib gettext git libncurses-dev libssl-dev \
python3-distutils python3-setuptools rsync swig unzip zlib1g-dev file wget

Older advice (for 19.07 and earlier that need python2.7):

sudo apt update
sudo apt install build-essential ccache ecj fastjar file g++ gawk \
gettext git java-propose-classpath libelf-dev libncurses5-dev \
libncursesw5-dev libssl-dev python python2.7-dev python3 unzip wget \
python3-distutils python3-setuptools python3-dev rsync subversion \
swig time xsltproc zlib1g-dev 

echo \
app-arch/{bzip2,sharutils,unzip,zip} sys-process/time \
app-text/asciidoc \
dev-libs/{libusb-compat,libxslt,openssl} dev-util/intltool \
dev-vcs/{git,mercurial} net-misc/{rsync,wget} \
sys-apps/util-linux sys-devel/{bc,bin86,dev86} \
sys-libs/{ncurses,zlib} virtual/perl-ExtUtils-MakeMaker \
| sed "s/\s/\n/g" \
| sort \
| sudo tee /etc/portage/sets/openwrt-prerequisites \
&& sudo emerge -DuvNa "@openwrt-prerequisites"

sudo zypper install --no-recommends asciidoc bash bc binutils bzip2 \
fastjar flex gawk gcc gcc-c++ gettext-tools git git-core intltool \
libopenssl-devel libxslt-tools make mercurial ncurses-devel patch \
perl-ExtUtils-MakeMaker python-devel rsync sdcc unzip util-linux \
wget zlib-devel

sudo xbps-install -Su asciidoc bash bc binutils bzip2 cdrtools \
coreutils diffutils findutils flex gawk gcc gettext git grep intltool \
libxslt linux-headers make ncurses-devel openssl-devel patch perl \
pkg-config python3-devel rsync tar unzip util-linux wget \
zlib-devel time libelf perl-ExtUtils-MakeMaker-CPANfile \
help2man swig
 
# for musl version, also install: argp-standalone musl-fts-devel musl-obstack-devel

macOS distribution-specific instructions. macOS uses Darwin unix as its core. Xcode/CLT toolchain, & 3rd-party package-manager tool allows to load various common build tools.
More info: buildroot.exigence.macosx.

sudo port install libiconv gettext-runtime coreutils findutils gwhich \
gawk zlib pcre bzip2 ncurses grep getopt gettext-tools-libs gettext \
diffutils sharutils util-linux libxslt libxml2 help2man readline gtime \
gnutar unzip zip lzma xz libelf fastjar libusb libftdi0 expat sqlite3 \
openssl3 openssl kerberos5 dbus lz4 libunistring nettle icu gnutls \
p11-kit wget quilt subversion gmake pkgconfig libzip cdrtools ccache \
curl xxhashlib rsync libidn perl5 p5.28-xml-parser p5.30-xml-parser \
p5-extutils-makemaker p5-data-dumper boost-jam boost boost-build bash \
bash-completion binutils m4 flex intltool patchutils swig git-extras \
git openjdk17 openjdk7-zulu luajit libtool glib2 file python27 \
python310 libzzip mercurial asciidoc sdcc gnu-classpath

Distribution-specific instructions.

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