Comment from Marco [here](https://github.com/bitcoin/bitcoin/pull/19954#discussion_r503075378):
> + make -C src --jobs=1 check-security V=1
make: Entering directory '/bitcoin/distsrc-x86_64-linux-gnu/src'
Checking binary security...
READELF=/gnu/store/pzq9s5ldl90h72p26jkdakyccdg9ib3k-profile/bin/x86_64-linux-gnu-readelf OBJDUMP=x86_64-linux-gnu-objdump OTOOL= /gnu/store/pzq9s5ldl90h72p26jkdakyccdg9ib3k-profile/bin/python3.7 ../contrib/devtools/security-check.py bitcoind  bitcoin-cli bitcoin-tx bitcoin-wallet test/test_bitcoin bench/bench_bitcoin qt/bitcoin-qt  
make: Leaving directory '/bitcoin/distsrc-x86_64-linux-gnu/src'
> + case "$HOST" in
> + make -C src --jobs=1 check-symbols V=1
make: Entering directory '/bitcoin/distsrc-x86_64-linux-gnu/src'
Checking glibc back compat...
READELF=/gnu/store/pzq9s5ldl90h72p26jkdakyccdg9ib3k-profile/bin/x86_64-linux-gnu-readelf CPPFILT=/gnu/store/pzq9s5ldl90h72p26jkdakyccdg9ib3k-profile/bin/x86_64-linux-gnu-c++filt /gnu/store/pzq9s5ldl90h72p26jkdakyccdg9ib3k-profile/bin/python3.7 ../contrib/devtools/symbol-check.py bitcoind  bitcoin-cli bitcoin-tx bitcoin-wallet test/test_bitcoin bench/bench_bitcoin qt/bitcoin-qt  
test/test_bitcoin: export of symbol in6addr_loopback not allowed
test/test_bitcoin: failed EXPORTED_SYMBOLS
make: *** [Makefile:20952: check-symbols] Error 1
make: Leaving directory '/bitcoin/distsrc-x86_64-linux-gnu/src'

**test/test_bitcoin: export of symbol in6addr_loopback not allowed**
BOOST_CHECK(!NetWhitebindPermissions::TryParse("", whitebindPermissions, error));
    /
    BOOST_CHECK(NetWhitebindPermissions::TryParse("1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK(error.empty());
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_ISIMPLICIT);
    BOOST_CHECK(NetPermissions::HasFlag(whitebindPermissions.m_flags, PF_ISIMPLICIT));
    NetPermissions::ClearFlag(whitebindPermissions.m_flags, PF_ISIMPLICIT);
    BOOST_CHECK(!NetPermissions::HasFlag(whitebindPermissions.m_flags, PF_ISIMPLICIT));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_NONE);
    NetPermissions::AddFlag(whitebindPermissions.m_flags, PF_ISIMPLICIT);
    BOOST_CHECK(NetPermissions::HasFlag(whitebindPermissions.m_flags, PF_ISIMPLICIT));
    /
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER);
    BOOST_CHECK(NetWhitebindPermissions::TryParse("@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_NONE);
    /
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,forcerelay@1.2.3.4:32", whitebindPermissions, error));
    /
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER | PF_FORCERELAY | PF_RELAY);
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,relay,noban@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER | PF_RELAY | PF_NOBAN);
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,forcerelay,noban@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK(NetWhitebindPermissions::TryParse("all@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_ALL);
    /
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,relay,noban,noban@1.2.3.4:32", whitebindPermissions, error));
    BOOST_CHECK_EQUAL(whitebindPermissions.m_flags, PF_BLOOMFILTER | PF_RELAY | PF_NOBAN);
    /
    BOOST_CHECK(NetWhitebindPermissions::TryParse("bloom,relay,,noban@1.2.3.4:32", whitebindPermissions, error));