Add bootstrap build for upb

[owent]

Fixes #15111 Fixes #13751

[ericsalo]

Thank you for this submission, it's clear you put a fair amount of effort into this and we appreciate it. Unfortunately we are already working on fixing the cmake support for upb in a way which ties it much more strongly to the existing protobuf cmake support.

[owent]

Thank you for this submission, it's clear you put a fair amount of effort into this and we appreciate it. Unfortunately we are already working on fixing the cmake support for upb in a way which ties it much more strongly to the existing protobuf cmake support.

Thank you, I have been eagerly awaiting this for months. Prior to the completion of this implementation, we have an internal patch to bootstrap build upb with Lua binding, and we also use gRPC (which depends on upb). However, the make_cmakelists.py has undergone significant changes in recent months, requiring us to repeatedly rework the patch. Therefore, I am wondering if we could use a temporary solution until the final implementation is completed.

[calvin2021y]

@ericsalo any news ?

[github-actions[bot]]

We triage inactive PRs and issues in order to make it easier to find active work. If this PR should remain active, please add a comment.

This PR is labeled inactive because the last activity was over 90 days ago. This PR will be closed and archived after 14 additional days without activity.

[github-actions[bot]]

We triage inactive PRs and issues in order to make it easier to find active work. If this PR should remain active or becomes active again, please reopen it.

This PR was closed and archived because there has been no new activity in the 14 days since the inactive label was added.