Кросс-компиляция

Ежли ты желаешь использовать программу, которой в настоящий момент нет в репозитарии OpenWrt, тебе совершенно необязательно ударяться в поиски нужного бинаря для твоего проца. Если прога опенсорсная, тебе всего-то достаточно скачать исходники и собрать прогу в билдруте.

Имей в виду, что далеко не все исходники можно собрать под твой проц, а производительность встроенных систем весьма ниже того, что ты имеешь на своем пентиуме.

• Здесь ты найдешь инструкцию как пользоваться OpenWrt Buildroot
• Locate the toolchain binaries in the staging_dir/toolchain-architecture_gcc-compilerver_uClibc-libcver/bin/ directory
• Add that directory to the PATH environment variable:
  • PATH=$PATH:(your toolchain/bin directory here)
  • export PATH
• Set the STAGING_DIR environment variable to the above toolchain dir and export it:
  • STAGING_DIR=(your toolchain directory here)
  • export STAGING_DIR
• Download and unpack the code to be compiled, change into the unpacked directory
• Pass the host and build to the build system of the package to trigger cross-compile
  • For GNU configure, use --build=architecture-unkown-linux-gnu --host=architecture-openwrt-linux-uclibc (for example: ./configure --build=x86_64-unkown-linux-gnu --host=mips-openwrt-linux-uclibc)
    • Run ./config.guess to get the --build= option.
    • Check the output and ensure that 'checking whether we are cross compiling... yes' is yes.
  • For GNU make, override the CC and LD environment variables (usually not needed if GNU configure was used)
    • make CC=architecture-openwrt-linux-uclibc-gcc LD=architecture-openwrt-linux-uclibc-ld
• The compiled program will be somewhere inside the folder your run ./configure and make from, try doing find -iname *program*
• Run file program to confirm cross-compiling was successful.
• If compilation aborts due to missing header files or shared objects, you might need to override CFLAGS and LDFLAGS to point to the staging_dir/target-architecture_uClibc-libcver/usr/include and .../usr/lib directories
• Debugging requires gdb in the toolchain. Default config does not include it. Include using make menuconfig. [Advanced configuration options→Toolchain Options→Build gdb]
• Remote debugging can be done using script ./scripts/remote-gdb

When compilation is finished, copy the resulting binary and related libraries to the target device to test it. It might be necessary to set LD_LIBRARY_PATH on the target to point the binary to libraries in non-standard locations.

If the program works well enough, you maybe want to build a real package for the opkg package manager and make it easily accessible for everyone out there. See Creating your own packages and Using Dependencies for further information on that.