When installing libbitcoin is there an option to deactivate the warnings?

Question

When installing libbitcoin from here with $ ./install.sh --prefix=/home/me/myprefix --build-boost --disable-shared after most of the compilation is done there are checks of the sourcecode with warnings like this one:

In file included from ./include/bitcoin/bitcoin/machine/operation.hpp:159:0,
                 from ./include/bitcoin/bitcoin/chain/script.hpp:31,
                 from ./include/bitcoin/bitcoin/chain/output.hpp:28,
                 from ./include/bitcoin/bitcoin/chain/output_point.hpp:25,
                 from ./include/bitcoin/bitcoin/chain/input.hpp:27,
                 from ./include/bitcoin/bitcoin/chain/transaction.hpp:30,
                 from ./include/bitcoin/bitcoin/chain/block.hpp:31,
                 from ./include/bitcoin/bitcoin.hpp:24,
                 from test/chain/transaction.cpp:20:
./include/bitcoin/bitcoin/impl/machine/operation.ipp:136:15: warning: ‘size_t libbitcoin::machine::variable_uint_size(uint64_t)’ defined but not used [-Wunused-function]
 static size_t variable_uint_size(uint64_t value)
               ^~~~~~~~~~~~~~~~~~

I was under the impression that the compiling was already finished and this is something that comes afterwards. During this process, which took half a day, my Pi runs out of HDD swap (1,7GB) and crashes. Is there an option to deactivate those warnings?