Is 'didn't use to / didn't used to' correct below?

Mike said 'I didn't use to like spare ribs; now I do.'
'I didn't used to' has no logical justification, but I see it increasingly in print. I don't recommend that you use it but, if you do, many people will not notice the 'error'.
As I have no doubt said here several times before, I hate "didn't use(d) to" in writing. It just looks horrible. Of course, if you are transcribing dialogue verbatim then you may have to bite the bullet. Outside of dialogue, use "used not to". It is nonsense to say that "used not to" is "rarely encountered" as your quote claims.
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I don't know how reliable this guy (Bryan Garner) is, but I found this info from him:

used to (2).
Today: “didn’t used to”; *”didn’t use to.”

“Didn’t used to” (= formerly didn’t) is the informal equivalent of the standard form “never used to” and the rarely encountered phrase “used not to” — e.g.:

o “‘Green’ didn’t used to be a popular word in the white world of skiing and snowboarding.” Gary Olson, “Environment Gets a Lift from Skiers,” Ariz. Republic, 30 Oct. 1994, at T1.

o “Ronnie Brown, Highland Park’s parks and recreation director, said Christmas lights didn’t used to be such a big deal in town.” Dan R. Barber, “Lights Fantastic,” Dallas Morning News, 11 Dec. 1996, at J1.

o “Choosing the car of the year is getting to be a messy business. It didn’t used to be that way.” Matt Nauman, “Here’s How One Auto Writer Picks ‘Of the Year’ Nominees,” Times Union (Albany), 19 Dec. 1996, at T10.

It shouldn’t be written *”didn’t use to,” although this point has stirred up some controversy among usage pundits. The argument goes that “didn’t” supplies the past tense, and the main verb that follows should be in the present tense, as it is in a sentence such as “You didn’t have [not 'had'] to do that.” But “used to” is an idiomatic phrase based on an archaic meaning of “use” (= to be in the habit of). The form of the verb is fixed in the positive “used to,” and is unchanged in the far less common (and far less accepted) negative form, “didn’t used to.”

How do we know this? After all, when the phrase is spoken, the “d” of “used” is drowned out by the “t” of “to.” The proponents of *”didn’t use to” make much of this, arguing that since we can’t resolve the usage question by listening to speakers, we have to decide on the basis of traditional grammar. But in fact, we can draw an inference from pronunciation of the “-s-” in “use” (/yooz/) and “used” (/yoost/), and it strongly supports the idiomatic phrase “didn’t used to.”

And in modern print sources, “didn’t used to” is about four times as common as *”didn’t use to.” When *”didn’t use to” does appear, it commonly occurs in transcribed speech — e.g.: “‘She was engulfed by a lake that didn’t use to [read 'didn't used to'] be there,’ said Michael Foster, a case manager.” Frank Stanfield & Lesley Clark, “Year’s Heavy Rains Still Aren’t Enough,” Orlando Sentinel, 2 Dec. 1994, at 1.

But remember the standard form that can save you headaches: “never used to.” It avoids the grammatical problem of “did” + [past tense]. It keeps “used.” And it doesn’t reek of dialect.
goronskyI don't know how reliable this guy (Bryan Garner) is,
Geoffrey Pullum has written of a chapter by Garner in the Chicago manual of style "His chapter is unfortunately full of repetitions of stupidities of the past tradition in English grammar – more of them than you could shake a stick at.... ".

Personally, I think Pullum is a little too restrained.
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 GPY's reply was promoted to an answer.