More and more languages are being built on top of the "upb" C library for protobuf (https://github.com/protocolbuffers/upb https://github.com/protocolbuffers/up

More and more languages are being built on top of the "upb" C library for protobuf (https://github.com/protocolbuffers/upb https://github.com/protocolbuffers/upb) which is designed around arenas to avoid this very problem. Currently Ruby, PHP, and Python are backed by upb. Disclosure: I work on the protobuf team, and created the upb library.