Update symbols_with_libdwarf.cpp

src/symbols/symbols_with_libdwarf.cpp

@@ -44,6 +44,8 @@ namespace libdwarf {
                 // .emplace needed, for some reason .insert tries to copy <= gcc 7.2
                 return resolver_map.emplace(object_name, std::move(resolver_object)).first->second.get();
             } else {
+                // gcc cannot handle the following logic properly in <= gcc 5.1, so the type to be constructed is explicitly specified. 
+                // See also:https://godbolt.org/z/9oWdWjbf8
                 return maybe_owned<symbol_resolver>{std::move(resolver_object)};
             }
         }