in log4j-api-scala_2.13/src/main/scala/org/apache/logging/log4j/scala/LoggerMacro.scala [318:322]
def logMsgThrowable(c: LoggerContext)(level: c.Expr[Level], message: c.Expr[Message], cause: c.Expr[Throwable]) =
c.universe.reify(
if (c.prefix.splice.delegate.isEnabled(level.splice)) {
c.prefix.splice.logMessage(level.splice, null, message.splice, cause.splice)
}