dnsdist fails to build with clang 4.0.0

[cpu82]

• Program: dnsdist
• Issue type: Bug report

Short description

dnsdist fails to build with clang 4.0 likely due to llvm-mirror/clang@4b6ad14285f3

% /usr/bin/clang -v
FreeBSD clang version 4.0.0 (branches/release_40 292009) (based on LLVM 4.0.0)
Target: x86_64-unknown-freebsd12.0
Thread model: posix
InstalledDir: /usr/bin

ext/json11/json11.cpp:153:24: error: invalid operands to binary expression
      ('nullptr_t' and 'nullptr_t')
        return m_value < static_cast<const Value<tag, T> *>(other)->m_value;
               ~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ext/json11/json11.cpp:209:5: note: in instantiation of member function
      'json11::Value<json11::Json::Type::NUL, nullptr_t>::less' requested here
    JsonNull() : Value(nullptr) {}
    ^

Full build log: http://sprunge.us/DWTf

Environment

• Operating system: FreeBSD 12.0-CURRENT/amd64
• Software version: dnsdist-1.1.0
• Software source: tar.gz

Steps to reproduce

1. build with CC="cc" CXX="c++" CPP="cpp" ./configure --bindir=/usr/local/sbin --enable-dnscrypt --enable-libsodium --enable-re2 --prefix=/usr/local

[rgacogne]

Thank you for reporting this. It looks like upstream 1 still has the same issue, so it should probably be reported there too. It would be easier for everyone to have an upstream fix.

[rgacogne]

Upstream fixed the issue in dropbox/json11#92, I'll check if we can easily backport the fix.