kotlin-fork/compiler/testData/diagnostics/tests/inference/builderInference/kt47986_2.diag.txt

/kt47986_2.kt:11:13: warning: type parameter for a type argument K can't be inferred into declared upper bounds. Please provide any use-site type information. It will become an error in future releases.
    val x = buildFoo { // can't infer
            ^^^^^^^^