>the vote on limiting Switzerland's population to 10 million

google searches 10 minutes after it passes: what is EU ‎guillotine clause

Switzerland has treaties with the EU. The EU would prefer a single treaty, Switzerland prefers lots of piecemeal treaties.

Current political climate in Switzerland is a bit like Brexit before Brexit: lots of populist blathering about how the EU exploits Switzerland so there are lots of votes in being anti-EU and in demanding "fair" deals ("fair" always means "more for me, less for you").

These treaties are currently being renegotiated -- I think some of them technically expired but both sides pretend they are still valid during the negotiations.

There are forces in Switzerland that would like to break one or more of the treaties and keep the others.

The EU won't like that so we got guillotine clauses = if one treaty is no longer valid, none of them are valid, to prevent the Swiss from playing funny games.

One of the Swiss complaints is fair: they provide roads for lots and lots of EU transit traffic.