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OpenWrt Buildroot – About

OpenWrt Buildroot is a set of Makefiles and patches that allows users to easily generate both a cross-compilation toolchain and a root filesystem for embedded systems. It is a heavily modified Buildroot. The cross-compilation toolchain uses uClibc, a tiny C standard library.

A compilation toolchain is the set of tools used to compile code for your system. It consists of:

a compiler (in our case, gcc / deb: gcc)
binary utils like assembler and linker (in our case, binutils / deb: binutils )
a C standard library (for example GNU Libc, uClibc or dietlibc).

Using a PC, the compilation toolchain runs on an x86 processor and generates code for a x86 processor. On most Linux systems, the compilation toolchain uses the GNU libc as C standard library. It is called the "host compilation toolchain", and the machine it is running on is called the "host system". The compilation toolchain is provided by the distribution, and has nothing to do with OpenWrt Buildroot.

Embedded systems use a different processor and require a cross-compilation toolchain - a compilation toolchain that runs on a host system but that generates code for a target system (and target processor's instruction set architecture (ISA). For example, if your host system uses x86 and your target system uses MIPS32, the regular compilation toolchain of your host runs on x86 and generates code for x86, while the cross-compilation toolchain runs on x86 and generates code for MIPS32.

While it is possible to manually configure and compile your own software, OpenWrt Buildroot automates this process to work on the instruction set architecture of most embedded systems.

While the OpenWrt Buildroot was designed for developers, inexperienced users can also use it to easily build their own custom firmware!