Another option is that the law isn't valid.

What, like make a law that says that laws that make reference to works that aren't freely available to the public aren't valid?

I'm no lawyer, so I don't know if there's a way to make a law invalidate another, other than by putting it in the constitution as an amendment.

No. Make the argument in court. The law really should be struck down if you can't have a copy of it. The court could hold that the law is unenforceable until the copyright expires.

That creates the weird situation where a law goes into effect on some seemingly random date in the future.

That already happens when laws are challenged

Ooh, I know - how about having a law refer to a standard copyrighted by Disney, that would be fun

> I'm no lawyer, so I don't know if there's a way to make a law invalidate another, other than by putting it in the constitution as an amendment.

Congress needs exemptions to not be affected by the laws they pass e.g. OSHA specifically exempts the US (and thus congress). Which means congress could pass a law preventing themselves from passing certain laws.

Though of course they could always repeal it first, I wouldn't think "unrepealable" laws would be constitutional.

> Which means congress could pass a law preventing themselves from passing certain laws.

So what happens in court when legislation didn't notice and passed the law regardless? Can a codified law that may even have already been used in previous cases be rendered null because another law says it shouldn't exist?

Yes. Happens often. Politically speaking, the Government is well known for dropping cases that may lead to unsatisfactory judgement or precedent rather than following through and putting up with the flurry of resulting appeals to vacate convictions based on a nullified law since judicial nullification is retroactive.

The trick to keeping something unchallenged is to only enforce it against people they are fairly certain they don't have to worry about challenging it in a substantial way. Only people with standing can challenge it, and once you're in a position to challenge it, your defense is unlikely to go down a route to nullify. Nevermind that there is a prevailing ethos of minimizing the impact of a decision on the body of case law, so it is extremely difficult to make a compelling argument to get a law nullified unless it is extremely and obviously egriegious in nature.

Congress cannot pass a law that binds future Congresses, the supreme court decided in Winstar (https://www.law.cornell.edu/supct/html/95-865.ZO.html)

A later congress can always legislate whatever it wants, even if it contradicts previous legislation.

Winstar is with respect to damage to a nongovernmental entity. Congress can affect Congress in other ways, such as changing its rules of session or changing the pay of its members, that do bind future Congresses. I'd say a rule against referencing nonpublic standards would be closer to the second than the first. (A future congress, of course, could change it back...)