[ARROW-4110] [C++] Do not generate distinct cast kernels when input and output type are the same

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.13.0
• Component/s: C++
• External issue URL: https://github.com/apache/arrow/issues/20701
• Assignee: Wes McKinney
• Reporter: Wes McKinney
• Created: 23/Dec/18 20:09
• Updated: 11/Jan/23 07:31
• Resolved: 15/Feb/19 05:01

Description

A side issue brought up by ARROW-4101 and ARROW-4102 is that the "identity cast" is handled on a type-by-type basis. We should see if we can have a "universal identity cast" and simplify things