Is omitting a specification of undefined behavior the sane thing to do, though?
I was thinking that "undefined behavior" in a spec is a serious misnomer. It's paradoxical if anything is defined as undefined, and it lets you confuse it with actually undefined behavior.
If something is in the spec as undefined behavior, it's my understanding it could legitimately lead to, say, global thermonuclear war. No guarantees.
But if something is not in the spec at all, say the effect of having your "const" keywords bright blue, then the spec is not sanctioning the end of the world happening as a consequence. The entire world provides constraints of reasonableness and other relationships that must hold.
This seems like an important difference! The latter is what I would call literally undefined; the standard version of undefined is (a) inherently defined as undefined, and (b) falsifies itself, because nobody would actually use a compiler that could cause the end of the world, ever.
The discussion of undefined behavior and the concomitant blaming of those who inadvertently invoke it have gradually come to be associated in my mind with the blaming of people for self-driving car crashes. They may not be related exactly, but homomorphic. It seems like popular and gradually spreading pathology in human thinking. Maybe it could be called "computism" after "corporatism".
I guess maybe the issue is that the world is mostly composed of "unknown unknowns" and it is incredibly attractive to a lot of programmers to declare them Somebody Else's Problem. But I'm tentatively suggesting you can never just disclaim those "unknown unknowns" and therefore you should never fall into the trap of trying to define the undefined. It's a vast ocean, not a few drops of water you can build a fence around. Unfortunately this sounds, even to me, like vague philosophical meanderings, but I strongly feel that there is something like an intellectual prion disease out there, and that impression has been building ever since I was browsing comp.lang.c.* in the 90s.
Undefined behavior exists in a spec for efficiency reasons. For example, accessing an out of bound index in C remains undefined as Having the runtime check boundaries on every index access is an inefficiency reserved for less efficient language specs like python.
Rust aims to solve these problems with something called zero cost abstractions.
I was thinking that "undefined behavior" in a spec is a serious misnomer. It's paradoxical if anything is defined as undefined, and it lets you confuse it with actually undefined behavior.
If something is in the spec as undefined behavior, it's my understanding it could legitimately lead to, say, global thermonuclear war. No guarantees.
But if something is not in the spec at all, say the effect of having your "const" keywords bright blue, then the spec is not sanctioning the end of the world happening as a consequence. The entire world provides constraints of reasonableness and other relationships that must hold.
This seems like an important difference! The latter is what I would call literally undefined; the standard version of undefined is (a) inherently defined as undefined, and (b) falsifies itself, because nobody would actually use a compiler that could cause the end of the world, ever.
The discussion of undefined behavior and the concomitant blaming of those who inadvertently invoke it have gradually come to be associated in my mind with the blaming of people for self-driving car crashes. They may not be related exactly, but homomorphic. It seems like popular and gradually spreading pathology in human thinking. Maybe it could be called "computism" after "corporatism".
I guess maybe the issue is that the world is mostly composed of "unknown unknowns" and it is incredibly attractive to a lot of programmers to declare them Somebody Else's Problem. But I'm tentatively suggesting you can never just disclaim those "unknown unknowns" and therefore you should never fall into the trap of trying to define the undefined. It's a vast ocean, not a few drops of water you can build a fence around. Unfortunately this sounds, even to me, like vague philosophical meanderings, but I strongly feel that there is something like an intellectual prion disease out there, and that impression has been building ever since I was browsing comp.lang.c.* in the 90s.