KtNameReferenceExpression(216,219): 'inc'
  KaCallResolutionError:
    candidateCalls = [
      KaSimpleFunctionCall:
        contextArgumentMapping = {}
        contextArguments = []
        dispatchReceiver = KaExplicitReceiverValue:
          expression = num
          isSafeNavigation = false
          type = kotlin.Int?
        extensionReceiver = null
        signature = KaFunctionSignature:
          receiverType = null
          returnType = kotlin.Int
          symbol = kotlin/Int.inc(<dispatch receiver>: kotlin.Int): kotlin.Int
          valueParameters = []
          contextParameters = []
          callableId = kotlin/Int.inc
        typeArgumentsMapping = {}
        valueArgumentMapping = {}
    ]
    diagnostic = ERROR<UNSAFE_CALL: Only safe (?.) or non-null asserted (!!.) calls are allowed on a nullable receiver of type 'Int?'.>
