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(!ResolveSubNet("::/0").Match(ResolveIP("::")));
    BOOST_CHECK(!ResolveSubNet("::/0").Match(ResolveIP("0.0.0.0")));
    
    BOOST_CHECK(!ResolveSubNet("::/0").Match(ResolveIP("1.2.3.4")));
    
    BOOST_CHECK(!ResolveSubNet("0.0.0.0/0").Match(ResolveIP("1:2:3:4:5:6:7:1234")));
    
    BOOST_CHECK(!CSubNet().Match(ResolveIP("1.2.3.4")));
    BOOST_CHECK(!ResolveSubNet("").Match(ResolveIP("4.5.6.7")));
    BOOST_CHECK(!ResolveSubNet("bloop").Match(ResolveIP("0.0.0.0")));
    BOOST_CHECK(!ResolveSubNet("bloop").Match(ResolveIP("hab")));
    
    BOOST_CHECK(ResolveSubNet("1.2.3.0/0").IsValid());
    BOOST_CHECK(!ResolveSubNet("1.2.3.0/-1").IsValid());
    BOOST_CHECK(ResolveSubNet("1.2.3.0/32").IsValid());
    BOOST_CHECK(!ResolveSubNet("1.2.3.0/33").IsValid());
    BOOST_CHECK(!ResolveSubNet("1.2.3.0/300").IsValid());
    BOOST_CHECK(ResolveSubNet("1:2:3:4:5:6:7:8/0").IsValid());
    BOOST_CHECK(ResolveSubNet("1:2:3:4:5:6:7:8/33").IsValid());
    BOOST_CHECK(!ResolveSubNet("1:2:3:4:5:6:7:8/-1").IsValid());
    BOOST_CHECK(ResolveSubNet("1:2:3:4:5:6:7:8/128").IsValid());
    BOOST_CHECK(!ResolveSubNet("1:2:3:4:5:6:7:8/129").IsValid());
    BOOST_CHECK(!ResolveSubNet("fuzzy").IsValid());
    
    BOOST_CHECK(CSubNet(ResolveIP("127.0.0.1")).IsValid());
    BOOST_CHECK(CSubNet(ResolveIP("127.0.0.1")).Match(ResolveIP("127.0.0.1")));
    BOOST_CHECK(!CSubNet(ResolveIP("127.0.0.1")).Match(ResolveIP("127.0.0.2")));
    BOOST_CHECK(CSubNet(ResolveIP("127.0.0.1")).ToString() == "127.0.0.1/32");
    CSubNet subnet = CSubNet(ResolveIP("1.2.3.4"), 32);