There is NOTHING in the GPL (v1, v2 nor v3, nor any sub license alternative) that says the source code has to compile or that an executable be supplied with source code to use the GPL. The quote you reference (and I read it too, I've read the GPL numerous times!) states that if you DO supply a binary, i.e., "executable work", you must also supply all the source files including compiler scripts used for that binary when you distribute under the GPL. There is nothing in the GPL that says the code has to be executable, has to function correctly, nor has to compile from what you distribute under the GPL. The GPL is a copyright license, not a consumer protection law. It just states that if you code it, the source is made available to anyone that wants to use it or modify it, and that the modifications stay under the ascribed GPL license. That's all, nothing else, thank you for playing. Don't let the door hit you on the way out.
And since you're obviously too lazy to bother to follow links to find information on the web, here:
I use public key cryptography to sign my code to assure its authenticity. Is it true that GPLv3 forces me to release my private signing keys?
No. The only time you would be required to release signing keys is if you conveyed GPLed software inside a User Product, and its hardware checked the software for a valid cryptographic signature before it would function. In that specific case, you would be required to provide anyone who owned the device, on demand, with the key to sign and install modified software on his device so that it will run. If each instance of the device uses a different key, then you need only give each purchaser the key for his instance.
Palm, meet forehead.
Yup. Not an inexpensive uh-oh.
Surely the GPL requires all the source code required to build the supplied binary.
No it doesn't! You can publish code snippets under the GPL that don't compile at all until incorporated into something else. It's a source code license, not a binary license. If a binary is supplied it's a courtesy not a requirement.
Looks to me like the GPL requires those signing keys to be published if the source cannot be built into a running program without them.
Where, exactly did you look and find that misinformation? The word "compiler", not even compile, occurs once in the entire text of the GPL in the definitions section.
Well, the HR info would let them buy credit history and other such information so you would know who was having financial difficulties and might be able to be bought.
Medical records might contain information concerning addictions which could be used against them. Either with the addiction itself (giving them drugs or sending them on gambling vacations) or financially. If someone was having, or recently had, a major medical condition such as cancer then they might be having financial problems. There are plenty of ways to coerce someone. The more information that you have the more likely you will find that method.
Anyone with a security clearance (even low level clearances) have to have clean credit histories and have annual drug tests to maintain them. Your examples work for extorting money from individuals in non-classified positions in the government, not compromising national security. You also watch too much TV if you believe otherwise. The data stolen from OPM was for non-classified government employees. I can assure you that any post breach investigation would have found any possible soft targets and the problems would have been taken care of.
ATC and flying a plane are not even remotely similar programming problems. If you think they are, I suggest you do some more research and a lot more thinking. There are too many qualitative issues with air traffic and ground control to simply program around. Here's an example:
You have three flights with the exact same fuel load that need to land. One has a pregnant woman aboard that is going into labor or otherwise has a medical emergency, one has a convict on board being extradited and the other is full of families and others under normal travel conditions. How does the computer get notified of such conditions and how does it make the judgement to land one plane over the other two?
That kind of scenario plays out daily in the skies over the world, but no one says boo about it because it gets handled by a human that can make a value judgement on the fly without a code upgrade! Sorry, as long as there are humans involved anywhere in the model, even as cargo, there will always be conditions that you cannot program around. It's honestly one of the things that bugs me about self-driving cars. It'd be fine if everyone had them, but as long as there are humans behind the wheels of other cars, things like the odd deer that likes to jump in the road, bicyclists and pedestrians I still have some doubt in their current state. There are some talented programmers playing the what-if game and doing a superb job of defining the behavior of autonomous vehicles, but their creations aren't anywhere near what we can do with some simple rules and a brain when it comes to value judgements.
The two most common things in the Universe are hydrogen and stupidity. -- Harlan Ellison