Woodruff: Weird architectures weren't supported to begin with

Equally, though, at least in my jurisdiction, liability laws for anything only expect you to be liable for reasonably foreseeable consequences of your actions, and do allow for disclaimers of liability even for things like buildings and cars. Not total disclaimers, but (for example) the skylights for my house have a legally enforceable disclaimer of liability for faults other than manufacturing defects and undisclosed issues with the design.

The much more likely model for software liability here would be to copy consumer goods (everything from pens through to cars); in that model, the default liability for any product is limited to the price paid to you, and a full refund for the faulty goods is normally the limit of your liability. The only time where you have further liability beyond the purchase price paid to you is when you could foresee that the part you supplied would, when used correctly, cause the extra costs that the buyer has incurred; one way that you can foresee such things is if the buyer explicitly tells you about those extra costs.

So, for example, I buy a washing machine; it doesn't wash clothes and doesn't function. The seller's liability to me is limited to a full refund. I tell the seller that I need a washing machine that works because if I can't wash my clothes tonight, I'm going to have to spend £100 on new clothes tomorrow, and that is enough that the seller has to either refuse to deal with me (allowed, of course!), or is liable to me for £100 above a full refund.

And note that these only apply if the seller is acting as a business, not as a private individual; if I sell you my home-made 6m band dipole aerial, then caveat emptor applies (unless I'm producing aerials as a business).

For a practical example of how all of that interacts, consider the engines sold by Honda for other people to build into products. If I buy an iGXV800 from Honda on their normal terms, they are liable to me if the engine does not function, or fails in use, to the cost of refunding me for the engine in full. However, if I build that engine into a motorbike of my own design and sell it to you, Honda don't acquire any additional liability; if you have a catastrophic engine failure while riding it, Honda are still only liable for the cost of the engine, as they did not foresee the extra consequences of a failure while using it in a motorbike (it's not sold for that use). Had I bought a Honda CB300R motorbike, and sold it to you, Honda could now foresee the consequences of a catastrophic engine failure while riding it, and would have the extra liability that results.

Translated to open source terms, most projects would have no liability still - the default position is that you're liable to supply a full refund if it doesn't work, but as no money has changed hands, that's a non-effect. Samsung would be on the hook, however, if the software in a Samsung phone does not work, even if it includes open source, because money changed hands; even then, the normal limit is the money I paid for the phone. Tesla, on the other hand, could be on the hook for far more money, even if their FSD software is mostly open source, and even if the failure is caused by an open source component, because Tesla could predict that it might crash. The developer of (say) a computer vision component used in the FSD software, however, is only liable to Tesla for what they agreed to (as part of a contract), or the money paid by Tesla to them for the software (probably nothing if it's open source).