+ if [ "$AFXDP" ]; then
+ sudo make headers_install INSTALL_HDR_PATH=/usr
+ pushd tools/lib/bpf/
+ # Bulding with gcc because there are some issues in make files
+ # that breaks building libbpf with clang on Travis.
+ CC=gcc sudo make install
+ CC=gcc sudo make install_headers
+ sudo ldconfig
+ popd
+ # The Linux kernel defines __always_inline in stddef.h (283d7573), and
+ # sys/cdefs.h tries to re-define it. Older libc-dev package in xenial
+ # doesn't have a fix for this issue. Applying it manually.
+ sudo sed -i '/^# define __always_inline .*/i # undef __always_inline' \
+ /usr/include/x86_64-linux-gnu/sys/cdefs.h || true
+ EXTRA_OPTS="${EXTRA_OPTS} --enable-afxdp"
+ else
+ EXTRA_OPTS="${EXTRA_OPTS} --with-linux=$(pwd)"
+ echo "Installed kernel source in $(pwd)"
+ fi
+ popd