[Bug]: librdkafka does not build with lz4 1.10.0

[scasagrande]

What happened?

librdkafka depends on @lz4//:lz4_hc

• https://github.com/bazelbuild/bazel-central-registry/blob/main/modules/librdkafka/2.8.0.bcr.2/overlay/BUILD.bazel#L197

This target is private in 1.10.0

• https://github.com/bazelbuild/bazel-central-registry/blob/main/modules/lz4/1.10.0/overlay/BUILD.bazel#L23-L32
• https://github.com/bazelbuild/bazel-central-registry/blob/main/modules/lz4/1.10.0/overlay/BUILD.bazel#L3

But was public in 1.9.4.bcr.2

• https://github.com/bazelbuild/bazel-central-registry/blob/main/modules/lz4/1.9.4.bcr.2/patches/add_build_file.patch#L31-L45

Version

N/A

How to reproduce

Depend on the latest versions of these bazel deps and attempt to build librdkafka.

Any other information?

No response

[scasagrande]

@vtsao-openai @daemoninstitute

[daemoninstitute]

Hi, I've looked into this and I believe the issue lies in librdkafka relying on :lz4_hc due to a confusing dependency structure in previous versions of the LZ4 bazel files. In v1.10.0, :lz4 is a unified target, and so :lz4_hc is now a private and internal implementation detail.

I believe the fix is to just change "@lz4//:lz4_hc" to "@lz4//:lz4" in modules/librdkafka/2.8.0.bcr.2/overlay/BUILD.bazel. I've done a local test build with this change, and librdkafka successfully builds.

For now you should be fine just using 1.9.4.bcr.2 unless you need the multithreading feature on the LZ4 CLI tool.

[daemoninstitute]

After further thought and investigation, i believe the best course of action is to revert the targets to match prior versions, as done in #5922. Sorry for any inconvenience caused and please tag me if there are any issues.

[scasagrande]

Thanks!!