...
When you believe that your patch is ready to be committed, select the Submit Patch link on the issue's JIRA. Folks should run ant clean package test before selecting Submit Patch. Unit tests will run automatically if the file is named according to the naming standards. See Hive PreCommit Patch Testing. Tests should all pass. If your patch involves performance optimizations, they should be validated by benchmarks that demonstrate an improvement.
If your patch creates an incompatibility with the latest major release, then you must set the Incompatible change flag on the issue's JIRA 'and' fill in the Release Note field with an explanation of the impact of the incompatibility and the necessary steps users must take.
...