[MacPorts] #62158: py-protobuf3: install failures for macOS 10.8 through 10.11: compilation error related to PROTOBUF_MAYBE_CONSTEXPR MapFieldBase(ConstantInitialized)

[MacPorts]

#62158: py-protobuf3: install failures for macOS 10.8 through 10.11: compilation
error related to PROTOBUF_MAYBE_CONSTEXPR MapFieldBase(ConstantInitialized)
---------------------------+-------------------------
  Reporter:  mascguy       |      Owner:  Schamschula
      Type:  defect        |     Status:  assigned
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:
Resolution:                |   Keywords:
      Port:  py-protobuf3  |
---------------------------+-------------------------

Comment (by mascguy):

 In the near-term, I'm offering to assist with testing on these older macOS
 releases. Can you propose some fixes?

-- 
Ticket URL: <https://trac.macports.org/ticket/62158#comment:13>
MacPorts <https://www.macports.org/>
Ports system for macOS