Clang : error on explicit specialization of 'CLASS_NAME'

[olivier-stasse]

On clang, when calling the macro DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN in feature-pose.cpp:

sot_ws/src/sot/sot-core/src/feature/feature-pose.cpp:45:13: error: explicit specialization of 'CLASS_NAME' after instantiation
template <> DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN(FeaturePose_t, "FeaturePose");
             ^
/usr/local/include/dynamic-graph/factory.h:28:32: note: expanded from macro 'DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN'
   const std::string CLASSTYPE::CLASS_NAME = CLASSNAME;                         \
                                ^
sot_ws/src/sot/sot-core/include/sot/core/feature-pose.hh:172:39: note: explicit instantiation first required here
 extern template class SOT_CORE_DLLAPI FeaturePose<R3xSO3Representation>;
                                       ^
sot_ws/src/sot/sot-core/src/feature/feature-pose.cpp:47:1: error: explicit specialization of 'CLASS_NAME' after instantiation
 DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN(FeaturePoseSE3_t, "FeaturePoseSE3");
 ^
 /usr/local/include/dynamic-graph/factory.h:28:32: note: expanded from macro 'DYNAMICGRAPH_FACTORY_ENTITY_PLUGIN'
   const std::string CLASSTYPE::CLASS_NAME = CLASSNAME;                         \
                                ^
sot_ws/src/sot/sot-core/include/sot/core/feature-pose.hh:171:39: note: explicit instantiation first required here
 extern template class SOT_CORE_DLLAPI FeaturePose<SE3Representation>;

clang version:

Apple clang version 11.0.3 (clang-1103.0.32.62)
Target: x86_64-apple-darwin19.6.0
Thread model: posix