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When translating `==` for reference types, the backend now uses `Objects.equals` instead of a null check and `Object.equals`. One motivation is to remove avoidable synthetic branches/instructions for null data that are interpreted as uncovered code by JaCoCo etc. It also reduces bytecode size. We recently started using `Objects.hashCode` for the synthetic `hashCode` implementation in value classes. Note that if either operand is potentially `Number` or `Character`, the backend delegates to `BoxesRuntime.equals` which handles Scala semantic edge cases for boxed primitives. This change does not affect that path. Forward-port of Scala 2 PR 11212
sjrd
approved these changes
Feb 19, 2026
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When translating
==for reference types, the backend now usesObjects.equalsinstead of a null check andObject.equals.One motivation is to remove avoidable synthetic branches/instructions for null data that are interpreted as uncovered code by JaCoCo etc.
It also reduces bytecode size.
We recently started using
Objects.hashCodefor the synthetichashCodeimplementation in value classes.Note that if either operand is potentially
NumberorCharacter, the backend delegates toBoxesRuntime.equalswhich handles Scala semantic edge cases for boxed primitives. This change does not affect that path.Forward-port of scala/scala#11212