Error 2, Toolchain directory '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/staging_dir/rsdk-4.6.4-4181-EB-3.10-0.9.33-m32u-20141001/' does not exist

[vido89]

Testing external toolchain for ipv6 support ... Toolchain directory '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/staging_dir/rsdk-4.6.4-4181-EB-3.10-0.9.33-m32u-20141001/' does not exist.
failed
ERROR: CONFIG_IPV6 is enabled but the external toolchain does not support it
Makefile:62: recipe for target '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/build_dir/toolchain-mips-rlx4181-linux/wrapper-1/.prepared' failed
make[3]: *** [/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/build_dir/toolchain-mips-rlx4181-linux/wrapper-1/.prepared] Error 1
make[3]: Leaving directory '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/toolchain/wrapper'
toolchain/Makefile:86: recipe for target 'toolchain/wrapper/prepare' failed
make[2]: *** [toolchain/wrapper/prepare] Error 2
make[2]: Leaving directory '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk'
toolchain/Makefile:85: recipe for target '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/staging_dir/toolchain-mips-rlx4181-linux/stamp/.toolchain_install' failed
make[1]: *** [/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/staging_dir/toolchain-mips-rlx4181-linux/stamp/.toolchain_install] Error 2
make[1]: Leaving directory '/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk'
/home/slobodan/Desktop/openwrt_rtk-master/rtk_openwrt_sdk/include/toplevel.mk:171: recipe for target 'world' failed
make: *** [world] Error 2

[lcharles123]

Its because http://cadinfo.realtek.com.tw/svn/CN/jungle/trunk/toolchain/rsdk/uclibc/rsdk-4.6.4-5281-EB-3.10-0.9.33-m32ub-20141001.tar.bz2 is unavailable.

You can use this repository to get an old version of theses sdks (rsdk-4.4.7) https://github.com/mzpqnxow/realtek-mips-sdks/
Also you need multiarch support to compile this code, if no it will cause "missing executable files"

dpkg --add-architecture i386
sudo apt update
sudo apt install zlib1g:i386