Would you rather have the system to auto correct invalid date input, or an error message saying you need to correct it?

What do you think would be the preferred way of handling invalid date input on a desktop GUI?

Let's say the user needs to set a date range, e.g. for a search. And he sets the start date to 2018-06-01 and the end date to 2018-05-02, i.e. the end date is before the start date.

Alternative number 1 is that the system auto correct the end date, to the same date as the start date. There might be a highlighting animation informing the user that something was changed (however, he might miss it if he does not look at that input during that second).

Alternative number 2 is that we just display an error message, and the user will have to correct the error himself.