[SPARK-33702] Result of add "unused-locals" compile arg to scalac

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 3.1.0, 3.2.0
• Component/s: Build
• Assignee: Unassigned
• Reporter: Yang Jie
• Created: 08/Dec/20 05:45
• Updated: 12/Dec/22 18:10

Description

Try to add "unused-locals" compile arg to scalac and collect the warning informations, there are total 184 files and 296 compile warnings about  "unused-locals":

• core: 92 warnings
• mllib-local\mllib:  42 warnings
• graphx: 6 warnings
• streaming: 14 warnings
• Sql\hive\avro: 81 warnings
• Yarn\mesos\k8s: 23 warnings
• kafka: 3 warnings
• kinesis-asl: 4 warnings
• examples: 31  warnings