kotlin-fork/compiler/testData/codegen/box/operatorConventions/kt4987.kt

// IGNORE_BACKEND_FIR: JVM_IR
fun box(): String {
    operator fun Int?.inc() = (this ?: 0) + 1
    var counter: Int? = null
    counter++
    return if (counter == 1) "OK" else "fail: $counter"
}