1BR2_arm=y 2BR2_TOOLCHAIN_EXTERNAL=y 3BR2_TOOLCHAIN_EXTERNAL_CUSTOM=y 4BR2_TOOLCHAIN_EXTERNAL_DOWNLOAD=y 5BR2_TOOLCHAIN_EXTERNAL_URL="http://autobuild.buildroot.org/toolchains/tarballs/br-arm-basic-2020.11.2.tar.bz2" 6BR2_TOOLCHAIN_EXTERNAL_GCC_9=y 7BR2_TOOLCHAIN_EXTERNAL_HEADERS_5_9=y 8# BR2_TOOLCHAIN_EXTERNAL_HAS_THREADS_DEBUG is not set 9