When gnuradio is built, it halts as follows.
Scanning dependencies of target volk
[ 0%] Building C object volk/lib/CMakeFiles/volk.dir/constants.c.o
Linking C shared library libvolk.so
[ 1%] Built target volk
make[2]: Warning: File `/usr/lib/arm-linux-gnueabihf/libboost_filesystem.so' has modification time 1.4e+08 s in the future
Linking CXX executable test_all
libvolk.so.0.0.0: undefined reference to `volk_32fc_x2_multiply_32fc_neonasm'
libvolk.so.0.0.0: undefined reference to `volk_16i_max_star_horizontal_16i_neonasm'
libvolk.so.0.0.0: undefined reference to `volk_32fc_32f_dot_prod_32fc_a_neonasm'
libvolk.so.0.0.0: undefined reference to `volk_32f_x2_dot_prod_32f_neonasm_opts'
libvolk.so.0.0.0: undefined reference to `volk_32fc_32f_dot_prod_32fc_a_neonpipeline'
libvolk.so.0.0.0: undefined reference to `volk_32f_x2_dot_prod_32f_neonasm'
collect2: error: ld returned 1 exit status
make[2]: *** [volk/lib/test_all] Error 1
make[1]: *** [volk/lib/CMakeFiles/test_all.dir/all] Error 2
make: *** [all] Error 2
Build failed. See output above for error messages.