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**
{
    std::string hostOut;
    int portOut = -1;
    SplitHostPort(test, portOut, hostOut);
    return hostOut == host && port == portOut;
}
BOOST_AUTO_TEST_CASE(netbase_splithost)
{
    BOOST_CHECK(TestSplitHost("www.bitcoincore.org", "www.bitcoincore.org", -1));
    BOOST_CHECK(TestSplitHost("[www.bitcoincore.org]", "www.bitcoincore.org", -1));
    BOOST_CHECK(TestSplitHost("www.bitcoincore.org:80", "www.bitcoincore.org", 80));
    BOOST_CHECK(TestSplitHost("[www.bitcoincore.org]:80", "www.bitcoincore.org", 80));
    BOOST_CHECK(TestSplitHost("127.0.0.1", "127.0.0.1", -1));
    BOOST_CHECK(TestSplitHost("127.0.0.1:8333", "127.0.0.1", 8333));
    BOOST_CHECK(TestSplitHost("[127.0.0.1]", "127.0.0.1", -1));
    BOOST_CHECK(TestSplitHost("[127.0.0.1]:8333", "127.0.0.1", 8333));
    BOOST_CHECK(TestSplitHost("::ffff:127.0.0.1", "::ffff:127.0.0.1", -1));
    BOOST_CHECK(TestSplitHost("[::ffff:127.0.0.1]:8333", "::ffff:127.0.0.1", 8333));
    BOOST_CHECK(TestSplitHost("[::]:8333", "::", 8333));
    BOOST_CHECK(TestSplitHost("::8333", "::8333", -1));
    BOOST_CHECK(TestSplitHost(":8333", "", 8333));
    BOOST_CHECK(TestSplitHost("[]:8333", "", 8333));
    BOOST_CHECK(TestSplitHost("", "", -1));
}
bool static TestParse(std::string src, std::string canon)