[MacPorts] #63785: rspamd @3.1: builds failing for macOS 10.12 and earlier

[MacPorts]

#63785: rspamd @3.1: builds failing for macOS 10.12 and earlier
----------------------+----------------------
  Reporter:  mascguy  |      Owner:  mascguy
      Type:  defect   |     Status:  assigned
  Priority:  Normal   |  Milestone:
 Component:  ports    |    Version:  2.7.1
Resolution:           |   Keywords:
      Port:  rspamd   |
----------------------+----------------------

Comment (by mascguy):

 We're getting closer to fixing the build: The previous updates have solved
 many of the issues, with the remaining ones in the main top-level client
 cxx file `src/client/rspamc.cxx`:

 {{{
 rspamd/work/rspamd-3.5/src/libutil/cxx/util.hxx:101:48: error: no type
 named 'size_type' in 'std::allocator<char>'
         using size_type = typename std::allocator<T>::size_type;
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~

 In file included from rspamd/work/rspamd-3.5/src/client/rspamc.cxx:24:
 /opt/local/include/libcxx/v1/vector:482:30: error: 'reference' is a
 protected member of 'std::__vector_base<char,
 rspamd::secure_mem_allocator<char>>'
     typedef typename __base::reference               reference;
                              ^

 /opt/local/include/libcxx/v1/vector:483:30: error: 'const_reference' is a
 protected member of 'std::__vector_base<char,
 rspamd::secure_mem_allocator<char>>'
     typedef typename __base::const_reference         const_reference;
                              ^

 /opt/local/include/libcxx/v1/vector:485:30: error: 'difference_type' is a
 protected member of 'std::__vector_base<char,
 rspamd::secure_mem_allocator<char>>'
     typedef typename __base::difference_type         difference_type;
                              ^

 /opt/local/include/libcxx/v1/vector:486:30: error: 'pointer' is a
 protected member of 'std::__vector_base<char,
 rspamd::secure_mem_allocator<char>>'
     typedef typename __base::pointer                 pointer;
                              ^

 /opt/local/include/libcxx/v1/vector:487:30: error: 'const_pointer' is a
 protected member of 'std::__vector_base<char,
 rspamd::secure_mem_allocator<char>>'
     typedef typename __base::const_pointer           const_pointer;
                              ^
 }}}

 @kencu, is our version of `macports-libcxx` relatively recent, vis-a-vis
 upstream? Particularly related to C++ 2020 additions/changes?

-- 
Ticket URL: <https://trac.macports.org/ticket/63785#comment:16>
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