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kotlinlang

why is “this cast can never succeed” a warning and not an error?

There are cases when compiler might be wrong. E.g. if in some previous version of dependency it could succeed, but in current version cannot and you need compatibility.

it could be an error and support an annotation to turn it off?

is there a “treat warnings as errors” option?

A compiler flag `allWarningsAsErrors` is coming in Kotlin 1.2 <https://blog.jetbrains.com/kotlin/2017/10/kotlin-1-2-beta2-is-out/>