Protocol Buffers

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

C++

• Disable option sub-location mapping in open-source builds. (https://github.com/protocolbuffers/protobuf/commit/1d8a656f5273a3b41afa609cf0f08b65491dbd48)
• Add json_options.proto and json_enumvalue_options.proto and/or gencode derived from them to release artifacts (https://github.com/protocolbuffers/protobuf/commit/15e93345f8b821ad74334fd503318f8860b774bb)
• Json/upb: Implement json EnumValueName for upb (https://github.com/protocolbuffers/protobuf/commit/0e8519e927101be180f12bc6f064dbf525c5d517)
• Add deprecation warning for Reflection::GetEnum() and Reflection::GetRepeatedEnum(). (https://github.com/protocolbuffers/protobuf/commit/0bca2886d724d6782186ae970a0214b6fcc3e4e0)

Java

• Add json_options.proto and json_enumvalue_options.proto and/or gencode derived from them to release artifacts (https://github.com/protocolbuffers/protobuf/commit/15e93345f8b821ad74334fd503318f8860b774bb)
• Json/java: add json_name enumval support (https://github.com/protocolbuffers/protobuf/commit/bff6ed13255054eb8425f75f3b3f00af961f753d)

Python

• Add json_options.proto and json_enumvalue_options.proto and/or gencode derived from them to release artifacts (https://github.com/protocolbuffers/protobuf/commit/15e93345f8b821ad74334fd503318f8860b774bb)
• Emit future warning when mutating GetOptions() in OSS (https://github.com/protocolbuffers/protobuf/commit/22555418e7f3cc4e339134f0cbcea28931258ade)
• Emit deprecation warning when comparing descriptor containers with unrecognized types in OSS (https://github.com/protocolbuffers/protobuf/commit/5865e6b18c04b9276c8aeed4ed011a645cf06777)

PHP

• Reject Edition 2026 in the PHP generator. (https://github.com/protocolbuffers/protobuf/commit/020b9dbf530de51603344f73c021db1f9da96dea)

UPB (Python/PHP/Ruby C-Extension)

• Json/upb: Implement json EnumValueName for upb (https://github.com/protocolbuffers/protobuf/commit/0e8519e927101be180f12bc6f064dbf525c5d517)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Chore: add a unit test for .github/release_prep.sh (#26247) (https://github.com/protocolbuffers/protobuf/commit/8ccb4faa9bb9a53eca7b46f2775b291a1e288b92)
• Add Bazel9 test (https://github.com/protocolbuffers/protobuf/commit/90ad7e978849e11406eeb47baf228b099c5da9d0)
• Bazel 9 tests for csharp, hpb, objc, php, python, rust and upb (https://github.com/protocolbuffers/protobuf/commit/f9e028f29fa83d0fcfb01c19ce0a4635e9beff5c)

Compiler

• Make default_symbol_visibility STRICT in edition 2026 (https://github.com/protocolbuffers/protobuf/commit/fcd68c563cf2be486622a118caaf8c5f3858f744)
• Add deprecation warnings for (py|cc|java)_generic_service. (https://github.com/protocolbuffers/protobuf/commit/517be42cfe43c9e2c69f5ee40e437a9d8cbd3f99)
• Disallow reserving field number INT_MAX. (https://github.com/protocolbuffers/protobuf/commit/933c522f9e9a09d30f370dc885640af248e52469)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Feat: --<lang>_prefix cli option (#24824) (https://github.com/protocolbuffers/protobuf/commit/92dd27ccf0c5c674b48de48310e0ebf45d0d5b88)
• Enforce proto limits in the descriptor by default for EDITION_2026. (https://github.com/protocolbuffers/protobuf/commit/d8520d93af2aadf99afcb5e17bfb99c14ad57364)
• Fix: Apply path traversal guard to WriteAllToZip() matching WriteAllToDisk() (#27171) (https://github.com/protocolbuffers/protobuf/commit/28bef9809e4d1f5f3b6da2a4a26a3bd5b488136b)
• Add an enforce_proto_limits feature which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/5ddd5244f7a04539e59f97fbc0c0df02334d0b12)

C++

• Migrate top-level protobuf unittest protos from Edition 2024 to Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/271ca53b50bebdb4b910563928b1f7f3d5c61990)
• Util: validate Duration/Timestamp in TimeUtil::FromString against spec limits (#27443) (https://github.com/protocolbuffers/protobuf/commit/e33749537254d42895ef084e482faaba230fddc2)
• Make default_symbol_visibility STRICT in edition 2026 (https://github.com/protocolbuffers/protobuf/commit/fcd68c563cf2be486622a118caaf8c5f3858f744)
• Support assigning repeated scalar fields using Python Buffer API. (https://github.com/protocolbuffers/protobuf/commit/ea40f1d32a5e67b996ee487c1976e11535963cdc)
• Automated rollback of commit c8c5974fa928bf5c8752462119128e5e07a07919. (https://github.com/protocolbuffers/protobuf/commit/21ccdec2ffc6c5d21e5eac8efbe4bf14fa0516ed)
• Use the direct map reflection API when converting message to JSON, if the repeated field reflection is not valid. (https://github.com/protocolbuffers/protobuf/commit/e75aac33c3615d22d0cba61e8f9d92939a39a73f)
• [py/upb] Make GetOptions() return immutable options for scalar type. UPB will raise a TypeError when options returned GetOptions() by is mutated. (https://github.com/protocolbuffers/protobuf/commit/403d429eab9355a861fd20c1ddecf34c065e3533)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Fix(cpp): stop TextFormat iteration if output stream fails (#26237) (https://github.com/protocolbuffers/protobuf/commit/2718dd5f3dda891f7e0224e5f50aa946219499ff)
• Enforce proto limits in the descriptor by default for EDITION_2026. (https://github.com/protocolbuffers/protobuf/commit/d8520d93af2aadf99afcb5e17bfb99c14ad57364)
• Add an enforce_proto_limits feature which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/5ddd5244f7a04539e59f97fbc0c0df02334d0b12)
• Workaround for attribute handling bug in gcc < 13 (https://github.com/protocolbuffers/protobuf/commit/ba10a4e179fa6cd0cbe4597f6fd19c1b3442c5bd)
• Fix confusing error message for map value type name conflicts (https://github.com/protocolbuffers/protobuf/commit/7864b8534c4425ac98eee69b57600fd15ea8bf9b)
• C++Proto JSON: Align behavior on the type.proto path with the descriptor.proto path (https://github.com/protocolbuffers/protobuf/commit/0bc1f14c966a6714f757cdebf9dcc1f2ec3bb928)

Java

• Make Timestamps.parse() attempt non-lenient parsing first and warning if this fails. (https://github.com/protocolbuffers/protobuf/commit/d5e039a3021524ea1f1d68b2cf910f2379403a0e)
• Add a warning for potential OneofDescriptor collisions prior to Q1 2027 breaking changes. (https://github.com/protocolbuffers/protobuf/commit/ab6983138057ae4e2bc7ce4a7e8d853d5403913a)
• Make default_symbol_visibility STRICT in edition 2026 (https://github.com/protocolbuffers/protobuf/commit/fcd68c563cf2be486622a118caaf8c5f3858f744)
• Reject negative size in mergeDelimitedFrom (#28097) (https://github.com/protocolbuffers/protobuf/commit/c56cd5b4417249e091ccce3739b4e4176ac33403)
• Add deprecation warnings for (py|cc|java)_generic_service. (https://github.com/protocolbuffers/protobuf/commit/517be42cfe43c9e2c69f5ee40e437a9d8cbd3f99)
• Update Java protobuf generator to use Objects.requireNonNull (https://github.com/protocolbuffers/protobuf/commit/31ef11cb59a269acf8a20aa40373ae5c59a30a9f)
• Use natural String comparison instead of UTF-8 ByteString comparison for sorting map keys in JsonFormat. (https://github.com/protocolbuffers/protobuf/commit/ae1faeedfd57b2cdc4c26e7befe4d34138210494)
• Add option to enable strict JSON parsing in Protobuf Java JsonFormat. (https://github.com/protocolbuffers/protobuf/commit/40825a1df7f87857560a03bf901fdd7649930010)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Remove experimental FieldOrder enum. (https://github.com/protocolbuffers/protobuf/commit/ec52338ef068245df952ecbfcfee8ad3fb44a180)
• Optimize GeneratedMessage.ExtendableBuilder to avoid temporary allocations when merging empty extendable messages. (https://github.com/protocolbuffers/protobuf/commit/a37dbd643372b05de834190941671a1563d7e499)
• Stop using sun.misc.Unsafe in isValidUtf8 paths. (https://github.com/protocolbuffers/protobuf/commit/421d7451ef41e158cd1ec3b84709de4018500b82)
• Use String#encodedLength on JDK versions that support it (https://github.com/protocolbuffers/protobuf/commit/efca121a668ecc73ca010c9457ba35bf189c01ec)
• Add an enforce_proto_limits feature which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/5ddd5244f7a04539e59f97fbc0c0df02334d0b12)
• Java: limit numeric string length before BigDecimal parsing (#26908) (https://github.com/protocolbuffers/protobuf/commit/25e7005814c4b2dd1cd21519c6cf116380a5ad21)
• Validate java package and class against injection risks. (https://github.com/protocolbuffers/protobuf/commit/f8514d8c42af41fbaaa73cd095e5e16cf347a23f)

Csharp

• Make default_symbol_visibility STRICT in edition 2026 (https://github.com/protocolbuffers/protobuf/commit/fcd68c563cf2be486622a118caaf8c5f3858f744)
• Advertise that C# supports Edition 2026, and move C# Nullable Reference Type support into that edition. (https://github.com/protocolbuffers/protobuf/commit/a1f718cdd7703878f35a521cfdb019bc8e129004)
• First implementation of C# nullable reference types enablement using the current (unreleased) edition. (https://github.com/protocolbuffers/protobuf/commit/7a732d1fb803e2c8df600838e554ac3ebeb0c7ef)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Csharp: propagate recursion depth into JsonReplayTokenizer to honor Any nesting limit (#26835) (https://github.com/protocolbuffers/protobuf/commit/cee45bff13ca18981453b170ea1725d0119e858f)
• Fix csharp string interpolation in Timestamp.ToDateTime() exception message (#26341) (https://github.com/protocolbuffers/protobuf/commit/a29828239fcef702b485dddae09e13306b23fcd1)

Objective-C

• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• [ObjC] Add DEBUG-only validations to extension values in GPBMessage, along with tests. (https://github.com/protocolbuffers/protobuf/commit/290a5376ce07716d12c3035742760a2d88f2072d)

Rust

• Remove -release suffix from Rust Crates.io release if minor version >= 36 (https://github.com/protocolbuffers/protobuf/commit/e7b3391b436adf78d3cd4b8a972b397b7ead32b1)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• RustProto: Add the ability to iterate over the muts of a repeated message-typed field. (https://github.com/protocolbuffers/protobuf/commit/70590a527ee1929a3834a0e749d513635a2a091d)
• See also UPB changes below, which may affect Rust.

Python

• Migrate top-level protobuf unittest protos from Edition 2024 to Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/271ca53b50bebdb4b910563928b1f7f3d5c61990)
• Configure extra compile args in setup.py (#28264) (https://github.com/protocolbuffers/protobuf/commit/3aa022a269f193025f8288cd89e96075c08fea2f)
• Python: fix heap-use-after-free in MapIterator after map.clear() (#27257) (https://github.com/protocolbuffers/protobuf/commit/9e9dbae858f75c8b886f1aea642418150cb8aed0)
• Add PyDescriptorPool_FromSharedPool(std::shared_ptr) API (https://github.com/protocolbuffers/protobuf/commit/abdf212e92115bda18485e606a79c073e4d462de)
• Fix memory leak in PyUpb_Descriptor_GetExtensionRanges (https://github.com/protocolbuffers/protobuf/commit/3d31b0f7866af9b20ec2c61d414ceee10689a882)
• Warn on out-of-range pop index in upb repeated fields. (https://github.com/protocolbuffers/protobuf/commit/a70d12186520fabc0a5a1266cc8ec9e1981a9a80)
• Support assigning repeated scalar fields using Python Buffer API. (https://github.com/protocolbuffers/protobuf/commit/ea40f1d32a5e67b996ee487c1976e11535963cdc)
• Fix Pure Python map<string, ...> key handling for bytes lookups. (https://github.com/protocolbuffers/protobuf/commit/156a0b8dfc805fbe12e450683c4687f0a9a426f1)
• Change Python DescriptorDatabase FindFileContainingSymbol() to accept leading "." to match DescriptorPool and other languages (https://github.com/protocolbuffers/protobuf/commit/e86e536349fae60486f12a4b6fdb893e49ca520c)
• Faster Python cpp protos assignment to bytes/string fields. (https://github.com/protocolbuffers/protobuf/commit/593ab176d6f0dcf5e37ea78d71e88cdd197ae219)
• Serialize length-prefixed protos once (#27252) (https://github.com/protocolbuffers/protobuf/commit/e090f8ae778cb3513ee2ecb25bbd015ef1bbe6de)
• [py/upb] Make GetOptions() return immutable options for scalar type. UPB will raise a TypeError when options returned GetOptions() by is mutated. (https://github.com/protocolbuffers/protobuf/commit/403d429eab9355a861fd20c1ddecf34c065e3533)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Add mutex protection to DescriptorPool caches. (https://github.com/protocolbuffers/protobuf/commit/cecbbf41e43634c7c5b940dd336aa81b31fd4e5d)
• Refactor container comparison function in py/C++ and py/upb to return enum instead of integer. (https://github.com/protocolbuffers/protobuf/commit/c857f492242f889b2a5551b50e309d927cb77b57)
• Py JSON: Fix issue with depth enforcement on Struct/Value WKT paths. (https://github.com/protocolbuffers/protobuf/commit/cfcc4337aee2ce3a584210320152ae0c97c86894)
• Fix RepeatedContainer_pop to raise IndexError for out-of-bounds indices. (https://github.com/protocolbuffers/protobuf/commit/78a09ada5c0d2668e1e0aa7cab4ec88d3b33fcd9)

PHP

• [PHP] - Add configurable recursion_limit to mergeFromString / serializeToString (#27874) (https://github.com/protocolbuffers/protobuf/commit/5c5ee3c9c739f4a1c9b119a0eb4e1eab4d1cc6d0)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)
• Clarify FieldMask JSON warnings/errors in the situation of fields which aren't round-trip representable in JSON format. (https://github.com/protocolbuffers/protobuf/commit/0488596867d7a055467e469419146df1ac20a4b6)
• Add an enforce_proto_limits feature which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/5ddd5244f7a04539e59f97fbc0c0df02334d0b12)

PHP C-Extension

• [PHP] - Add configurable recursion_limit to mergeFromString / serializeToString (#27874) (https://github.com/protocolbuffers/protobuf/commit/5c5ee3c9c739f4a1c9b119a0eb4e1eab4d1cc6d0)
• See also UPB changes below, which may affect PHP C-Extension.

Ruby

• Drop support for Ruby 3.1 (https://github.com/protocolbuffers/protobuf/commit/7008dd1aa72bf60e507e2e64688784925e47568f)
• Add bazel targets for standalone plugin binaries (#23919) (https://github.com/protocolbuffers/protobuf/commit/81880fad1673797b6326a91582b2bf77069d505d)

UPB (Python/PHP/Ruby C-Extension)

• Avoid UB in upb by switching to the XCT section, which will run our constructors before the compiler-generated initializers. (https://github.com/protocolbuffers/protobuf/commit/58e5ac879bdf42316c1d6a7b8618e5c31d87360f)
• [py/upb] Make GetOptions() return immutable options for scalar type. UPB will raise a TypeError when options returned GetOptions() by is mutated. (https://github.com/protocolbuffers/protobuf/commit/403d429eab9355a861fd20c1ddecf34c065e3533)
• Clarify FieldMask JSON warnings/errors in the situation of fields which aren't round-trip representable in JSON format. (https://github.com/protocolbuffers/protobuf/commit/0488596867d7a055467e469419146df1ac20a4b6)
• Add Bazel9 test (https://github.com/protocolbuffers/protobuf/commit/90ad7e978849e11406eeb47baf228b099c5da9d0)
• Fixed two GCC-only issues around upb's generated extension registry. (https://github.com/protocolbuffers/protobuf/commit/d56b385bd602002a317e7fb92e458b1b15b9d163)
• Fix RepeatedContainer_pop to raise IndexError for out-of-bounds indices. (https://github.com/protocolbuffers/protobuf/commit/78a09ada5c0d2668e1e0aa7cab4ec88d3b33fcd9)

Other

• Add deprecation warning for internal_py_proto_library prior to Q1 2027 breaking changes. (https://github.com/protocolbuffers/protobuf/commit/a8d0be3d42e166b642358c7009ee649946b69f63)
• Update Bazel

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Bazel 9 tests for csharp, hpb, objc, php, python, rust and upb (#27598) (https://github.com/protocolbuffers/protobuf/commit/4469e3840bfa69ee3bd21721b402ff28076ecbab)
• Break protobuf dependency on Bazel's proto fragment. Only respect the Starlark versions of --proto_toolchain_for*. This is a breaking change from 35.0, but matches the behavior in 34.x. (https://github.com/protocolbuffers/protobuf/commit/1f99c52d771b86ca11274019c9b1a10280dd6050)

C++

• Add cord setters to repeated string fields. (https://github.com/protocolbuffers/protobuf/commit/6efa174ec6d455a4404b37f997daa69770ddde8f)

UPB (Python/PHP/Ruby C-Extension)

• Avoid UB in upb by switching to the XCT section, which will run our constructors before the compiler-generated initializers. (https://github.com/protocolbuffers/protobuf/commit/c35b97728f4782343a37e590a3fd97c80fbadc55)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Remove unused dependency on aspect_bazel_lib (https://github.com/protocolbuffers/protobuf/commit/784a77f6e7705df26380980927623c38d67990be)

C++

• Workaround for attribute handling bug in gcc < 13 (https://github.com/protocolbuffers/protobuf/commit/1a5c5c5d8a2292e73e82f8479e87266008b910c4)

upb

• Avoid theoretical overflow of uintptr_t in AddAllLinkedExtensions (https://github.com/protocolbuffers/protobuf/commit/08d520af12637296c7b902effdf351aa1fb30fa4)
• Fixed two GCC-only issues around upb's generated extension registry (https://github.com/protocolbuffers/protobuf/commit/33debf38ec37fa93f8236c3bb7694f57e1eecb5a)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Bazel 9 Support: Upgrade tests to Bazel 9 (https://github.com/protocolbuffers/protobuf/commit/3ee8d8a008a5696f61aa72327e2c4cf2ae068e00)
• Moved protocopt flag out of the cc dir, since it is not a c++-specific flag. (https://github.com/protocolbuffers/protobuf/commit/325d8dca2ffdc658824aa6b05d825dcb86cca2cb)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Change @protobuf//bazel/flags:prefer_prebuilt_proto flag to True. (https://github.com/protocolbuffers/protobuf/commit/f9f32d28007ae692a494e70d6a5e808069938843)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)

Compiler

• Implement the Edition 2026 naming style enforcement feature. This will help prevent field name collisions. (https://github.com/protocolbuffers/protobuf/commit/ae0d964699968a13977ceabfe7ed0127e125c624)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Fail writing files in protoc CLI if any file output path is relative. (https://github.com/protocolbuffers/protobuf/commit/3bf2b07b2a77c8c8840031a3ef5867acf1b97f30)
• Mangle types named XyzView if there is any direct sibling named Xyz (https://github.com/protocolbuffers/protobuf/commit/63d6ef01b0e669333dda6fd91728862725c38968)
• Improve the namespacing selected by rustc used for gencode types in errors. (https://github.com/protocolbuffers/protobuf/commit/ce2eb733c7cb025c13a20735e8a8d005ba0fe19e)
• Fully qualify scalar types in Kotlin/Native proto generator. (https://github.com/protocolbuffers/protobuf/commit/adc8d22a30cc8369d5976c8b2685374e938640a5)
• Change _opt() accessors to return an std::Option instead of protobuf::Optional (https://github.com/protocolbuffers/protobuf/commit/6ced6127bc5fb4d65ae0cbfad7a5625d7aceab23)
• Make Message's trait bounds much better for generic use (https://github.com/protocolbuffers/protobuf/commit/be1292fbe2fc84ad59b6365a7620625e30114181)
• Support more chars in type URLs in the C++ text-format parser. (https://github.com/protocolbuffers/protobuf/commit/3a87c6c1fd7fdb7f88540bf3f378f53d3ca1f00d)
• Validate Feature Support on Custom Options (https://github.com/protocolbuffers/protobuf/commit/34c1110d38f225b0edcb14db965d3a5130e3ab29)
• Trait clarity effort: introduce Singular trait, for types which are allowed as simple fields (https://github.com/protocolbuffers/protobuf/commit/cdbfaf118e9906c8ca7c27b641a8abafbd129b0b)
• Trait clarity improvement on Map traits (https://github.com/protocolbuffers/protobuf/commit/a8daa95057bab1ca7f62830a539dc549359df78f)

C++

• Workaround for attribute handling bug in gcc < 13 (https://github.com/protocolbuffers/protobuf/commit/78dc67e4d598d4e2ec8929105eb2ddbb4bf50935)
• Implement the Edition 2026 naming style enforcement feature. This will help prevent field name collisions. (https://github.com/protocolbuffers/protobuf/commit/ae0d964699968a13977ceabfe7ed0127e125c624)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Enhance ParseInfoTree to provide location of names and values. (https://github.com/protocolbuffers/protobuf/commit/1cb4fdb8eaaa60917cdbd23cf6f38fc5f1307054)
• Add integer overflow check to RepeatedPtrField::MergeFrom. (https://github.com/protocolbuffers/protobuf/commit/cb5fe976f319683934d8153bdedb21355ab2e008)
• Adding sanity check for ListFields reflection call (https://github.com/protocolbuffers/protobuf/commit/555360e3b52f63e9a29d075c5e6900f7db7fdd2c)
• Introduce Arena::UniquePtr and Arena::Ptr as smart pointers to better manage (https://github.com/protocolbuffers/protobuf/commit/bb002180b59c957e6b2f0dddecf0e90ef5a26723)
• Bug fix for edition 2024 visibility checking. Visibility checking was not properly applied to service method input and output types. This is now applied properly and will error if method input/output types do not have visibility to those messages. (https://github.com/protocolbuffers/protobuf/commit/5a56dee4de2b6e6ffcd963054d100fc610171427)
• Fixed data race in Python Free Threading by removing unnecessary SetHasBitForRepeated() call. (https://github.com/protocolbuffers/protobuf/commit/8c1a9a4b0163eded7d9ff0c255507ed3163caf1f)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Add proto2::sort/stable_sort utilities that behave as the standard ones but are optimized for Protobuf containers. (https://github.com/protocolbuffers/protobuf/commit/252281f6be6df834a0f64a7f8d085c0bd679d1da)
• Add proto2::erase/erase_if utilities that behave as the standard ones but are optimized for Protobuf containers. (https://github.com/protocolbuffers/protobuf/commit/dc9fb354dbb75c730cb57856a909015aac5d9595)
• Extend Abseil flag support for enums to include std::vector. (https://github.com/protocolbuffers/protobuf/commit/bd42ac6b29603d5ba62d05d8f0dac6064d959b0d)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)
• Add native Abseil flag support to protobuf message types. (https://github.com/protocolbuffers/protobuf/commit/ec42e190317343e78a5be17962a57e45e3ff439d)
• Support more chars in type URLs in the C++ text-format parser. (https://github.com/protocolbuffers/protobuf/commit/3a87c6c1fd7fdb7f88540bf3f378f53d3ca1f00d)
• Stripping empty options (https://github.com/protocolbuffers/protobuf/commit/d5d6d4c89ef7f23b847d9e4fa459e57a4393b28d)
• Creating generic MaybeAddError helper function (https://github.com/protocolbuffers/protobuf/commit/4bcf773b240132846e8dc3361b7e629fc0926ebb)
• Validate Feature Support on Custom Options (https://github.com/protocolbuffers/protobuf/commit/34c1110d38f225b0edcb14db965d3a5130e3ab29)
• Add bounds checks to UnsafeArenaExtractSubrange, ReleaseLast and SwapElements. (https://github.com/protocolbuffers/protobuf/commit/d124c2dc26841e5ee0b8d1505438fcf0660c9db0)
• Fix UTF-8 Validation of string extensions in C++ (https://github.com/protocolbuffers/protobuf/commit/0936f33595ef736726f191c087eaabbc5d1c5fc6)
• Remove first implementation of protobuf out of bounds enforcement. (https://github.com/protocolbuffers/protobuf/commit/507f86bd3a9acdffaff10a32e8b48456b2559783)
• Add native Abseil flag support to protobuf enums. (https://github.com/protocolbuffers/protobuf/commit/a203388028fc5e3374d30ff3a385202a330fbefb)
• Improve EINTR handling for close in zero_copy_stream_impl.h (https://github.com/protocolbuffers/protobuf/commit/a904af9cc8597eea47b3d4c657dd4f36eefa1145)
• Add cc_proto_library for MessageSet in //src/google/protobuf/bridge (https://github.com/protocolbuffers/protobuf/commit/6d23e8ec14908edda3fdb44027eb87b90499f789)

Java

• Add BytecodeClassName functions, matching helpers in the java GeneratorNames utility. (https://github.com/protocolbuffers/protobuf/commit/514aceb974fbd55031169b79d2bd9f7646157787)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Avoid toBigIntegerExact in JsonFormat to avoid degenerate parse behavior in the face of large exponents. (https://github.com/protocolbuffers/protobuf/commit/57093a8bd5cb44211f323519a0045b883475666f)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)
• Add native Abseil flag support to protobuf enums. (https://github.com/protocolbuffers/protobuf/commit/a203388028fc5e3374d30ff3a385202a330fbefb)

Csharp

• Implement WriteDelimitedTo(BufferWriter) (#21325) (https://github.com/protocolbuffers/protobuf/commit/407f4570b201293783f5416cdaae493366bc6b14)
• Add an "include" directory containing WKTs for Google.Protobuf.Tools nuget package. (https://github.com/protocolbuffers/protobuf/commit/6029d174f2eed7a64ad3a42182d08f2f3e66fcf6)

Objective-C

• ObjC: Block Roots from being created. (https://github.com/protocolbuffers/protobuf/commit/827411455abe4a62dd11b2c8afb15a594ff35b42)
• Fix naming convention in c_function extension syntax (https://github.com/protocolbuffers/protobuf/commit/e3bee077db853dc0d6e8e04d1e3071018e222faf)
• Modify unit tests to use c_function extension syntax via ifdefs (https://github.com/protocolbuffers/protobuf/commit/e1f2f5272097cfd44dac849d7906b11445e93d38)

Rust

• Mangle types named XyzView if there is any direct sibling named Xyz (https://github.com/protocolbuffers/protobuf/commit/63d6ef01b0e669333dda6fd91728862725c38968)
• Improve the namespacing selected by rustc used for gencode types in errors. (https://github.com/protocolbuffers/protobuf/commit/ce2eb733c7cb025c13a20735e8a8d005ba0fe19e)
• Allow ProtoStr to be used in const contexts. (https://github.com/protocolbuffers/protobuf/commit/7f7b974fce500ad67ddb9aaa517c0bd6796d479d)
• Make any &T impl AsView if T impl AsView (https://github.com/protocolbuffers/protobuf/commit/d787869082f031e561d0dc7f31e5cfc03848bd15)
• Change _opt() accessors to return an std::Option instead of protobuf::Optional (https://github.com/protocolbuffers/protobuf/commit/6ced6127bc5fb4d65ae0cbfad7a5625d7aceab23)
• Add some common methods to ProtoStr to make it more ergonomic to use without dropping down to &[u8] (https://github.com/protocolbuffers/protobuf/commit/f8daf2fabc8601e69c547fbf8c0addb6d6837e47)
• Ffi_11: Define basic arithmetic operations and comparison with underlying type (https://github.com/protocolbuffers/protobuf/commit/74b6f3fe0b9a80205309083ab88bd2ab012ed1eb)
• Make Message's trait bounds much better for generic use (https://github.com/protocolbuffers/protobuf/commit/be1292fbe2fc84ad59b6365a7620625e30114181)
• Remove ProxiedInMapValue alias, since it is superceded by MapValue (https://github.com/protocolbuffers/protobuf/commit/5bde6e8d3134cdf67a513cbff403d19526df11ad)
• Add fn push_default(&mut self) -> SomeMsgMut<> fn for Repeated message type fields. (https://github.com/protocolbuffers/protobuf/commit/a3bf3ec75512e8bc89334b2e245924ad15f6352c)
• Fix that f32 and f64 were incorrectly tagged as legal for MapKeys in RustProto. (https://github.com/protocolbuffers/protobuf/commit/ab3793e7a8f6270081cc0e74ba2ffd7b7ee35159)
• Trait clarity effort: introduce Singular trait, for types which are allowed as simple fields (https://github.com/protocolbuffers/protobuf/commit/cdbfaf118e9906c8ca7c27b641a8abafbd129b0b)
• Trait clarity improvement on Map traits (https://github.com/protocolbuffers/protobuf/commit/a8daa95057bab1ca7f62830a539dc549359df78f)
• See also UPB changes below, which may affect Rust.

Python

• Fix Python text_format by adding an optional recursion depth limit (#26604) (https://github.com/protocolbuffers/protobuf/commit/8abff6bb4b36575159bf247f3da62f4efa742bdd)
• Fix data race in CMessage lazy initialization for Python freethreading. (https://github.com/protocolbuffers/protobuf/commit/28e451233d38148856587c96bd8864b7e9767587)
• Fixed data race in Python Free Threading by removing unnecessary SetHasBitForRepeated() call. (https://github.com/protocolbuffers/protobuf/commit/8c1a9a4b0163eded7d9ff0c255507ed3163caf1f)
• Fix type annotation for FindAllExtensionNumbers() to be a list rather than the more general Iterator. (https://github.com/protocolbuffers/protobuf/commit/3edd61508bed8b58e5190b6c28884d3e21cf5bdc)
• Add type hints to descriptor_database.py. (https://github.com/protocolbuffers/protobuf/commit/cbe6403761a4fa349c6612102f048ff584441f09)
• Fixed a bug in msg.MergeFrom(msg2) in Python. (https://github.com/protocolbuffers/protobuf/commit/ab14c0f8ad88109b99205af9bd2ef961e991ea41)
• Fix NULL byte handling issue in Python Protobuf find symbols in pool (https://github.com/protocolbuffers/protobuf/commit/059dc7ed3256bd6c247694d92e624590c52a400a)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Add recursion guards for the following nested messages: (https://github.com/protocolbuffers/protobuf/commit/b4c3fecb8599b84967f293806d2db54aff77664b)
• Protobuf Python UPB Free Threading support. (https://github.com/protocolbuffers/protobuf/commit/f10c1de25fa7285a41978e5d054d03c48d19b9f1)
• Fix Any recursion depth bypass in Python json_format.ParseDict (#25239) (https://github.com/protocolbuffers/protobuf/commit/d2b001626d137c62dfee6c88c87324102531868b)
• Supports exporting int as int (https://github.com/protocolbuffers/protobuf/commit/ea78297e0a85dfd319381748d7c93dc69d2c5958)

PHP

• Fail writing files in protoc CLI if any file output path is relative. (https://github.com/protocolbuffers/protobuf/commit/3bf2b07b2a77c8c8840031a3ef5867acf1b97f30)

PHP C-Extension

• Fix 1-byte stack overflow in PHP extension int64 formatting (#26530) (https://github.com/protocolbuffers/protobuf/commit/3f045053e2a3fe55d0e3bf2b14d4d29e4f863fd5)
• See also UPB changes below, which may affect PHP C-Extension.

Ruby

• Gracefully handle payloads >2GB. (https://github.com/protocolbuffers/protobuf/commit/918ad5bff3f174a417dded6b58ceab4cf6720e65)

Ruby C-Extension

• Gracefully handle payloads >2GB. (https://github.com/protocolbuffers/protobuf/commit/918ad5bff3f174a417dded6b58ceab4cf6720e65)
• See also UPB changes below, which may affect Ruby C-Extension.

UPB (Python/PHP/Ruby C-Extension)

• Fixed two GCC-only issues around upb's generated extension registry.
• Avoid theoretical overflow of uintptr_t in AddAllLinkedExtensions (https://github.com/protocolbuffers/protobuf/commit/e7785e0509aab295692061fb569c00645d3ef3a4)
• Test(proto): Add message to test oneof name conflict resolution (https://github.com/protocolbuffers/protobuf/commit/29476e1a91dc3dfbc10a8d4a5bce998896452258)
• Add recursion guards for the following nested messages: (https://github.com/protocolbuffers/protobuf/commit/b4c3fecb8599b84967f293806d2db54aff77664b)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Bazel 9 Support: Upgrade tests to Bazel 9 (https://github.com/protocolbuffers/protobuf/commit/3ee8d8a008a5696f61aa72327e2c4cf2ae068e00)

C++

• Workaround for attribute handling bug in gcc < 13 (https://github.com/protocolbuffers/protobuf/commit/78dc67e4d598d4e2ec8929105eb2ddbb4bf50935)

UPB (Python/PHP/Ruby C-Extension)

• Fixed two GCC-only issues around upb's generated extension registry. (https://github.com/protocolbuffers/protobuf/commit/5eca43d66df4253b2b18b4dd46399cf1fbd1a061)
• Avoid theoretical overflow of uintptr_t in AddAllLinkedExtensions (https://github.com/protocolbuffers/protobuf/commit/e7785e0509aab295692061fb569c00645d3ef3a4)

Announcements

• This version includes potential breaking changes without a major version bump to: Bazel.
  • [Bazel] Change @protobuf//bazel/flags:prefer_prebuilt_proto flag to True. (https://github.com/protocolbuffers/protobuf/commit/f9f32d28007ae692a494e70d6a5e808069938843)
• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Moved protocopt flag out of the cc dir, since it is not a c++-specific flag. (https://github.com/protocolbuffers/protobuf/commit/325d8dca2ffdc658824aa6b05d825dcb86cca2cb)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Breaking change: Change @protobuf//bazel/flags:prefer_prebuilt_proto flag to True. (https://github.com/protocolbuffers/protobuf/commit/f9f32d28007ae692a494e70d6a5e808069938843)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)

Compiler

• Implement the Edition 2026 naming style enforcement feature. This will help prevent field name collisions. (https://github.com/protocolbuffers/protobuf/commit/ae0d964699968a13977ceabfe7ed0127e125c624)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Fail writing files in protoc CLI if any file output path is relative. (https://github.com/protocolbuffers/protobuf/commit/3bf2b07b2a77c8c8840031a3ef5867acf1b97f30)
• Mangle types named XyzView if there is any direct sibling named Xyz (https://github.com/protocolbuffers/protobuf/commit/63d6ef01b0e669333dda6fd91728862725c38968)
• Improve the namespacing selected by rustc used for gencode types in errors. (https://github.com/protocolbuffers/protobuf/commit/ce2eb733c7cb025c13a20735e8a8d005ba0fe19e)
• Fully qualify scalar types in Kotlin/Native proto generator. (https://github.com/protocolbuffers/protobuf/commit/adc8d22a30cc8369d5976c8b2685374e938640a5)
• Change _opt() accessors to return an std::Option instead of protobuf::Optional (https://github.com/protocolbuffers/protobuf/commit/6ced6127bc5fb4d65ae0cbfad7a5625d7aceab23)
• Make Message's trait bounds much better for generic use (https://github.com/protocolbuffers/protobuf/commit/be1292fbe2fc84ad59b6365a7620625e30114181)
• Support more chars in type URLs in the C++ text-format parser. (https://github.com/protocolbuffers/protobuf/commit/3a87c6c1fd7fdb7f88540bf3f378f53d3ca1f00d)
• Validate Feature Support on Custom Options (https://github.com/protocolbuffers/protobuf/commit/34c1110d38f225b0edcb14db965d3a5130e3ab29)
• Trait clarity effort: introduce Singular trait, for types which are allowed as simple fields (https://github.com/protocolbuffers/protobuf/commit/cdbfaf118e9906c8ca7c27b641a8abafbd129b0b)
• Trait clarity improvement on Map traits (https://github.com/protocolbuffers/protobuf/commit/a8daa95057bab1ca7f62830a539dc549359df78f)

C++

• Implement the Edition 2026 naming style enforcement feature. This will help prevent field name collisions. (https://github.com/protocolbuffers/protobuf/commit/ae0d964699968a13977ceabfe7ed0127e125c624)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Enhance ParseInfoTree to provide location of names and values. (https://github.com/protocolbuffers/protobuf/commit/1cb4fdb8eaaa60917cdbd23cf6f38fc5f1307054)
• Add integer overflow check to RepeatedPtrField::MergeFrom. (https://github.com/protocolbuffers/protobuf/commit/cb5fe976f319683934d8153bdedb21355ab2e008)
• Adding sanity check for ListFields reflection call (https://github.com/protocolbuffers/protobuf/commit/555360e3b52f63e9a29d075c5e6900f7db7fdd2c)
• Introduce Arena::UniquePtr and Arena::Ptr as smart pointers to better manage (https://github.com/protocolbuffers/protobuf/commit/bb002180b59c957e6b2f0dddecf0e90ef5a26723)
• Bug fix for edition 2024 visibility checking. Visibility checking was not properly applied to service method input and output types. This is now applied properly and will error if method input/output types do not have visibility to those messages. (https://github.com/protocolbuffers/protobuf/commit/5a56dee4de2b6e6ffcd963054d100fc610171427)
• Fixed data race in Python Free Threading by removing unnecessary SetHasBitForRepeated() call. (https://github.com/protocolbuffers/protobuf/commit/8c1a9a4b0163eded7d9ff0c255507ed3163caf1f)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Add proto2::sort/stable_sort utilities that behave as the standard ones but are optimized for Protobuf containers. (https://github.com/protocolbuffers/protobuf/commit/252281f6be6df834a0f64a7f8d085c0bd679d1da)
• Add proto2::erase/erase_if utilities that behave as the standard ones but are optimized for Protobuf containers. (https://github.com/protocolbuffers/protobuf/commit/dc9fb354dbb75c730cb57856a909015aac5d9595)
• Extend Abseil flag support for enums to include std::vector. (https://github.com/protocolbuffers/protobuf/commit/bd42ac6b29603d5ba62d05d8f0dac6064d959b0d)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)
• Add native Abseil flag support to protobuf message types. (https://github.com/protocolbuffers/protobuf/commit/ec42e190317343e78a5be17962a57e45e3ff439d)
• Support more chars in type URLs in the C++ text-format parser. (https://github.com/protocolbuffers/protobuf/commit/3a87c6c1fd7fdb7f88540bf3f378f53d3ca1f00d)
• Stripping empty options (https://github.com/protocolbuffers/protobuf/commit/d5d6d4c89ef7f23b847d9e4fa459e57a4393b28d)
• Creating generic MaybeAddError helper function (https://github.com/protocolbuffers/protobuf/commit/4bcf773b240132846e8dc3361b7e629fc0926ebb)
• Validate Feature Support on Custom Options (https://github.com/protocolbuffers/protobuf/commit/34c1110d38f225b0edcb14db965d3a5130e3ab29)
• Add bounds checks to UnsafeArenaExtractSubrange, ReleaseLast and SwapElements. (https://github.com/protocolbuffers/protobuf/commit/d124c2dc26841e5ee0b8d1505438fcf0660c9db0)
• Fix UTF-8 Validation of string extensions in C++ (https://github.com/protocolbuffers/protobuf/commit/0936f33595ef736726f191c087eaabbc5d1c5fc6)
• Remove first implementation of protobuf out of bounds enforcement. (https://github.com/protocolbuffers/protobuf/commit/507f86bd3a9acdffaff10a32e8b48456b2559783)
• Add native Abseil flag support to protobuf enums. (https://github.com/protocolbuffers/protobuf/commit/a203388028fc5e3374d30ff3a385202a330fbefb)
• Improve EINTR handling for close in zero_copy_stream_impl.h (https://github.com/protocolbuffers/protobuf/commit/a904af9cc8597eea47b3d4c657dd4f36eefa1145)
• Add cc_proto_library for MessageSet in //src/google/protobuf/bridge (https://github.com/protocolbuffers/protobuf/commit/6d23e8ec14908edda3fdb44027eb87b90499f789)

Java

• Add BytecodeClassName functions, matching helpers in the java GeneratorNames utility. (https://github.com/protocolbuffers/protobuf/commit/514aceb974fbd55031169b79d2bd9f7646157787)
• Add enum to enforce_naming_style feature to avoid field naming collisions which will be implemented in Edition 2026. (https://github.com/protocolbuffers/protobuf/commit/e4911a17241386611643972b977edaf2ce83468f)
• Avoid toBigIntegerExact in JsonFormat to avoid degenerate parse behavior in the face of large exponents. (https://github.com/protocolbuffers/protobuf/commit/57093a8bd5cb44211f323519a0045b883475666f)
• Dropped support for Bazel 7. (https://github.com/protocolbuffers/protobuf/commit/181675806987071b1a9af6e22b881cf9c3dca73e)
• Add native Abseil flag support to protobuf enums. (https://github.com/protocolbuffers/protobuf/commit/a203388028fc5e3374d30ff3a385202a330fbefb)

Csharp

• Implement WriteDelimitedTo(BufferWriter) (#21325) (https://github.com/protocolbuffers/protobuf/commit/407f4570b201293783f5416cdaae493366bc6b14)
• Add an "include" directory containing WKTs for Google.Protobuf.Tools nuget package. (https://github.com/protocolbuffers/protobuf/commit/6029d174f2eed7a64ad3a42182d08f2f3e66fcf6)

Objective-C

• ObjC: Block Roots from being created. (https://github.com/protocolbuffers/protobuf/commit/827411455abe4a62dd11b2c8afb15a594ff35b42)
• Fix naming convention in c_function extension syntax (https://github.com/protocolbuffers/protobuf/commit/e3bee077db853dc0d6e8e04d1e3071018e222faf)
• Modify unit tests to use c_function extension syntax via ifdefs (https://github.com/protocolbuffers/protobuf/commit/e1f2f5272097cfd44dac849d7906b11445e93d38)

Rust

• Mangle types named XyzView if there is any direct sibling named Xyz (https://github.com/protocolbuffers/protobuf/commit/63d6ef01b0e669333dda6fd91728862725c38968)
• Improve the namespacing selected by rustc used for gencode types in errors. (https://github.com/protocolbuffers/protobuf/commit/ce2eb733c7cb025c13a20735e8a8d005ba0fe19e)
• Allow ProtoStr to be used in const contexts. (https://github.com/protocolbuffers/protobuf/commit/7f7b974fce500ad67ddb9aaa517c0bd6796d479d)
• Make any &T impl AsView if T impl AsView (https://github.com/protocolbuffers/protobuf/commit/d787869082f031e561d0dc7f31e5cfc03848bd15)
• Change _opt() accessors to return an std::Option instead of protobuf::Optional (https://github.com/protocolbuffers/protobuf/commit/6ced6127bc5fb4d65ae0cbfad7a5625d7aceab23)
• Add some common methods to ProtoStr to make it more ergonomic to use without dropping down to &[u8] (https://github.com/protocolbuffers/protobuf/commit/f8daf2fabc8601e69c547fbf8c0addb6d6837e47)
• Ffi_11: Define basic arithmetic operations and comparison with underlying type (https://github.com/protocolbuffers/protobuf/commit/74b6f3fe0b9a80205309083ab88bd2ab012ed1eb)
• Make Message's trait bounds much better for generic use (https://github.com/protocolbuffers/protobuf/commit/be1292fbe2fc84ad59b6365a7620625e30114181)
• Remove ProxiedInMapValue alias, since it is superceded by MapValue (https://github.com/protocolbuffers/protobuf/commit/5bde6e8d3134cdf67a513cbff403d19526df11ad)
• Add fn push_default(&mut self) -> SomeMsgMut<> fn for Repeated message type fields. (https://github.com/protocolbuffers/protobuf/commit/a3bf3ec75512e8bc89334b2e245924ad15f6352c)
• Fix that f32 and f64 were incorrectly tagged as legal for MapKeys in RustProto. (https://github.com/protocolbuffers/protobuf/commit/ab3793e7a8f6270081cc0e74ba2ffd7b7ee35159)
• Trait clarity effort: introduce Singular trait, for types which are allowed as simple fields (https://github.com/protocolbuffers/protobuf/commit/cdbfaf118e9906c8ca7c27b641a8abafbd129b0b)
• Trait clarity improvement on Map traits (https://github.com/protocolbuffers/protobuf/commit/a8daa95057bab1ca7f62830a539dc549359df78f)
• See also UPB changes below, which may affect Rust.

Python

• Fix Python text_format by adding an optional recursion depth limit (#26604) (https://github.com/protocolbuffers/protobuf/commit/8abff6bb4b36575159bf247f3da62f4efa742bdd)
• Fix data race in CMessage lazy initialization for Python freethreading. (https://github.com/protocolbuffers/protobuf/commit/28e451233d38148856587c96bd8864b7e9767587)
• Fixed data race in Python Free Threading by removing unnecessary SetHasBitForRepeated() call. (https://github.com/protocolbuffers/protobuf/commit/8c1a9a4b0163eded7d9ff0c255507ed3163caf1f)
• Fix type annotation for FindAllExtensionNumbers() to be a list rather than the more general Iterator. (https://github.com/protocolbuffers/protobuf/commit/3edd61508bed8b58e5190b6c28884d3e21cf5bdc)
• Add type hints to descriptor_database.py. (https://github.com/protocolbuffers/protobuf/commit/cbe6403761a4fa349c6612102f048ff584441f09)
• Fixed a bug in msg.MergeFrom(msg2) in Python. (https://github.com/protocolbuffers/protobuf/commit/ab14c0f8ad88109b99205af9bd2ef961e991ea41)
• Fix NULL byte handling issue in Python Protobuf find symbols in pool (https://github.com/protocolbuffers/protobuf/commit/059dc7ed3256bd6c247694d92e624590c52a400a)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/f08d70329211dfd74584c3761da5da5e32ab34f3)
• Add recursion guards for the following nested messages: (https://github.com/protocolbuffers/protobuf/commit/b4c3fecb8599b84967f293806d2db54aff77664b)
• Protobuf Python UPB Free Threading support. (https://github.com/protocolbuffers/protobuf/commit/f10c1de25fa7285a41978e5d054d03c48d19b9f1)
• Fix Any recursion depth bypass in Python json_format.ParseDict (#25239) (https://github.com/protocolbuffers/protobuf/commit/d2b001626d137c62dfee6c88c87324102531868b)
• Supports exporting int as int (https://github.com/protocolbuffers/protobuf/commit/ea78297e0a85dfd319381748d7c93dc69d2c5958)

PHP

• Fail writing files in protoc CLI if any file output path is relative. (https://github.com/protocolbuffers/protobuf/commit/3bf2b07b2a77c8c8840031a3ef5867acf1b97f30)

PHP C-Extension

• Fix 1-byte stack overflow in PHP extension int64 formatting (#26530) (https://github.com/protocolbuffers/protobuf/commit/3f045053e2a3fe55d0e3bf2b14d4d29e4f863fd5)
• See also UPB changes below, which may affect PHP C-Extension.

Ruby

• Gracefully handle payloads >2GB. (https://github.com/protocolbuffers/protobuf/commit/918ad5bff3f174a417dded6b58ceab4cf6720e65)

Ruby C-Extension

• Gracefully handle payloads >2GB. (https://github.com/protocolbuffers/protobuf/commit/918ad5bff3f174a417dded6b58ceab4cf6720e65)
• See also UPB changes below, which may affect Ruby C-Extension.

UPB (Python/PHP/Ruby C-Extension)

• Test(proto): Add message to test oneof name conflict resolution (https://github.com/protocolbuffers/protobuf/commit/29476e1a91dc3dfbc10a8d4a5bce998896452258)
• Add recursion guards for the following nested messages: (https://github.com/protocolbuffers/protobuf/commit/b4c3fecb8599b84967f293806d2db54aff77664b)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Java

• Avoid toBigIntegerExact in JsonFormat to avoid degenerate parse behavior in the face of large exponents. (#26435) (https://github.com/protocolbuffers/protobuf/commit/f125aa53d9fee9137411b4fe5e25270d36139fab)
• Switch the pre22 warning to use CopyOnWriteArraySet. (#23976) (https://github.com/protocolbuffers/protobuf/commit/9822fb584f57dad3d8781d8cfb6013954bc4b2ac)

Python

• [numpy] Fix breakage in users of Python protobufs under NumPy 2.3rc1. (#22172) (https://github.com/protocolbuffers/protobuf/commit/a4508d4da5d82ac45692ea5a74bd7e2f922391f8)

Other

• Remove python from UPB / Windows tests (#26497) (https://github.com/protocolbuffers/protobuf/commit/73be936bc527069312519d9d56f5ba95857c92ed)
• Fix failing tests in 25.x (#25198) (https://github.com/protocolbuffers/protobuf/commit/2418c40990fd578444f1794e856daedefd298db6)
• Change setup-ruby and add new xcode version to build (https://github.com/protocolbuffers/protobuf/commit/9717aac2633e37135f57767061e1b29b4d4bb6b7)
• Protobuf: update php from macos-13 to macos-15-intel (https://github.com/protocolbuffers/protobuf/commit/1d18bbd02da912a7e52171dafe783cafbccb4415)
• Update GitHub Actions to use macOS-14 (again). (https://github.com/protocolbuffers/protobuf/commit/3c282a4ecac1f060c58e85afa9600413e3a9db24)
• Update GitHub Actions to use macOS-14. (https://github.com/protocolbuffers/protobuf/commit/2e1a0ccf07c09d6160d5b3c96787409a2162a942)
• Disable php tests (https://github.com/protocolbuffers/protobuf/commit/56f2fd2dd0f406072d168419f6e0afcc548a6050)
• Fix merge conflict annotations (https://github.com/protocolbuffers/protobuf/commit/b7abd06d7ba6afd5e5c3e4c1d678584af1dc1f52)
• Don't ignore platform requirements (https://github.com/protocolbuffers/protobuf/commit/a53de52c69bbc8c5552d89a23330eba3b566d4b4)
• Upgrade setup-php to speed up PHP tests (#24408) (https://github.com/protocolbuffers/protobuf/commit/0f2128fe3efcad71dd631f4c63cab19e52243fb1)
• Extend gencode compatibility support back to 3.20.0 (#22424) (https://github.com/protocolbuffers/protobuf/commit/6fbcb8724c63b92456d124344d4b16bcbaa8534b)
• Update github major version tags to be formatted v..<MI… (#22359) (https://github.com/protocolbuffers/protobuf/commit/974b235a71635d5a6c9a89614c5c781aea1307c7)
• Drop windows-2019 runners from CI (#22185) (https://github.com/protocolbuffers/protobuf/commit/9910104d6bb80d3cecc695b3b4ffaa299cb28337)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

Bazel

• Moved protocopt flag out of the cc dir, since it is not a c++-specific flag. (https://github.com/protocolbuffers/protobuf/commit/3db9fd1be16917f26590eccd6dfb51b8dcad0d15)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/763c5da3ff011a49f1c00992cdf9b4924d6b74bb)

C++

• Updated CMake dependencies. (https://github.com/protocolbuffers/protobuf/commit/5583485833ba82a21e15c53d2efcc61720731cb4)
• Add cc_proto_library for MessageSet in //src/google/protobuf/bridge (https://github.com/protocolbuffers/protobuf/commit/523a6a4758f5e3cae7f10dad5b08941588946ff3)
• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/763c5da3ff011a49f1c00992cdf9b4924d6b74bb)

Java

• Avoid toBigIntegerExact in JsonFormat to avoid degenerate parse behavior in the face of large exponents. (https://github.com/protocolbuffers/protobuf/commit/ab3d7f0041b22af4a61b6184fc2ac25092968840)

Python

• Add support for bazel 9.x (#26201) (https://github.com/protocolbuffers/protobuf/commit/763c5da3ff011a49f1c00992cdf9b4924d6b74bb)

Other

• Fixed release_prep.sh script mkdir command to follow INTEGRITY_FILE location. (https://github.com/protocolbuffers/protobuf/commit/e700d7d6478f3a8800fbcf7f156a0675c1c96392)
• Second try at fixing the release_prep.sh file path! (#26097) (https://github.com/protocolbuffers/protobuf/commit/f5ccaf3b4e4c5122bacc8d6e4832dd339ec9e81e)

Announcements

• Protobuf News may include additional announcements or pre-announcements for upcoming changes.

C++

• Add cc_proto_library for MessageSet in //src/google/protobuf/bridge (https://github.com/protocolbuffers/protobuf/commit/56be356e51513d778684d4cad70ae77fb3547ab9)

Java

• Avoid toBigIntegerExact in JsonFormat to avoid degenerate parse behavior in the face of large exponents. (https://github.com/protocolbuffers/protobuf/commit/e5158117475b36a8e8c7456c144b96a7f67a7649)

PHP

• Check that readRaw does not accept negative length value. (https://github.com/protocolbuffers/protobuf/commit/60e93d2d104f2af9cd345b1c6f3891d91430244a)
• Php: Fix that recursion limit is not enforced. (https://github.com/protocolbuffers/protobuf/commit/c8e9b27d95c6ab2d0668b5889e7dac2c477b7038)
• Chore(php): fix php 8.5 deprecations 33.x (#25714) (https://github.com/protocolbuffers/protobuf/commit/a594f973eb3eeb443e83e0c6aacd112c7be94243)
• Bump version dependencies on phpunit/phpunit to ">=10.5.62 <11.0.0" (https://github.com/protocolbuffers/protobuf/commit/7c0d2a2402eecf5d3196b7d6491ff8ad3b0a6203)