What Changed

Protocol Buffers (protobuf), Google's widely adopted data interchange format, has undergone several recent updates focusing on build system integration, compiler support, and internal development processes. Key changes include the introduction of Bzlmod support for Bazel 8+, updates to the Bazel CI presubmit matrix, and the removal of older GCC versions from GitHub Actions testing in favor of GCC 10.

Specifically, the project now explicitly supports Bazel with Bzlmod for Bazel 8 and newer versions, allowing users to specify protobuf as a dependency in their MODULE.bazel file. This modernizes the Bazel integration, offering an alternative to the traditional WORKSPACE approach. Concurrently, the .bazelci configuration has been updated to remove macOS (Intel Macs) from the presubmit matrix, revise Debian and Ubuntu distributions, and incorporate Bazel 9.x testing.

In terms of compiler support, the .github workflow for C++ testing has been refined. GitHub Actions matrix entries testing GCC versions prior to GCC 10 (specifically 7.5, 9.1, and 9.5) have been removed, and a GCC 10.4 test has been added. This aligns the testing infrastructure with the project's current support matrix, ensuring compatibility with more recent compiler versions.