[MacPorts] #61751: Building protobuf3-cpp :info:build ./google/protobuf/map_field.h:332:37: error: constexpr constructor never produces a constant expression [-Winvalid-constexpr]

[MacPorts]

#61751: Building protobuf3-cpp :info:build ./google/protobuf/map_field.h:332:37:
error: constexpr constructor never produces a constant expression
[-Winvalid-constexpr]
-----------------------+-----------------------
 Reporter:  dbl001     |      Owner:  (none)
     Type:  defect     |     Status:  new
 Priority:  Normal     |  Milestone:
Component:  ports      |    Version:  2.6.4
 Keywords:  protobuf3  |       Port:  protobuf3
-----------------------+-----------------------
 OS X 10.11.6
 {{{
 :info:build In file included from google/protobuf/dynamic_message.cc:80:
 :info:build ./google/protobuf/map_field.h:332:37: error: constexpr
 constructor never produces a constant expression [-Winvalid-constexpr]
 :info:build   explicit PROTOBUF_MAYBE_CONSTEXPR
 MapFieldBase(ConstantInitialized)
 :info:build                                     ^
 :info:build ./google/protobuf/map_field.h:335:9: note: non-literal type
 'internal::WrappedMutex' cannot be used in a constant expression
 :info:build         mutex_(GOOGLE_PROTOBUF_LINKER_INITIALIZED),
 :info:build         ^
 :info:build 1 error generated.
 :info:build make[2]: *** [google/protobuf/dynamic_message.lo] Error 1

 }}}

-- 
Ticket URL: <https://trac.macports.org/ticket/61751>
MacPorts <https://www.macports.org/>
Ports system for macOS