Joshua Haberman 28e451233d Fix data race in CMessage lazy initialization for Python freethreading. ... This change introduces a `LazyUniquePtr` class to manage the lazy initialization of `composite_fields` and `child_submessages` within `CMessage`. When Python's GIL is disabled, `LazyUniquePtr` uses atomic operations to ensure thread-safe initialization of these maps, preventing data races when multiple threads concurrently access fields that trigger their creation. A new test case is added to reproduce and verify the fix for a race condition in `GetFieldValue`. We are forced to use placement new and placement delete for the `LazyUniquePtr` members, because the `CMessage` struct is currently not properly constructed or destroyed. This makes the code a bit awkward, but changing the construction/destruction of CMessage seemed like too much to bite off in this CL. PiperOrigin-RevId: 891703488		2026-03-30 07:23:10 -07:00
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protobuf	Fix data race in CMessage lazy initialization for Python freethreading.	2026-03-30 07:23:10 -07:00
__init__.py	drop-deprecated-pkg-resources-declare (#22442)	2025-07-11 11:09:55 -07:00