11–20 of 196 posts
I suspect 99.9% of uses of std::unreachable would be better replaced by abort. (There will be those times when the code is correct and the optimisation gains are worth it -- but they will be rare).
I understand why it's there, but I do find it fun that when many people are trying to reduce undefined behaviour in their code, std::unreachable is literally defined as "this is undefined behaviour, use that to optimise". I suspect 99.9% of uses of std::unreachable would be better replaced by abort. (There will be those times when the code is correct and the optimisation gains are worth it -- but they will be rare).
I felt physically ill when I read:
It’s intended to be used when you know you have an execution path in your code that cannot be reached but the compiler cannot figure that out.
It felt like saying to the compiler, "please, find a way to make my program break even more easily". Exactly not what I need.
Why is it called "byteswap" and not "bytereverse"? "Swapping" can be done in any number of ways, but only one way to reverse.
Hmm. How often do people actaully want to std::byteswap as opposed to "convert this value from native byte order to big-endian" or "convert this value from little-endian to native byte order"? i.e., the functions documented in https://man7.org/linux/man-pages/man3/endian.3.html (why oh why are they not also documented in the GNU C Library Manual...)
Maybe having something like convert_be() and convert_le(), one of which is a no-op and the other does the byteswap (depending on your arch) would be better. It removes the duplication of e.g. htobe() and betoh() which are exactly the same function, while allowing the caller to not worry about which architecture their code is compiled on.
Why is it called "byteswap" and not "bytereverse"? "Swapping" can be done in any number of ways, but only one way to reverse.
I understand why it's there, but I do find it fun that when many people are trying to reduce undefined behaviour in their code, std::unreachable is literally defined as "this is undefined behaviour, use that to optimise". I suspect 99.9% of uses of std::unreachable would be better replaced by abort. (There will be those times when the code is correct and the optimisation gains are worth it -- but they will be rare).
+100 I felt physically ill when I read: It’s intended to be used when you know you have an execution path in your code that cannot be reached but the compiler cannot figure that out. It felt like saying to the compiler, "please, find a way to make my program break even more easily". Exactly not what I need.
Why is it called "byteswap" and not "bytereverse"? "Swapping" can be done in any number of ways, but only one way to reverse.
Reversing bytes sounds like reversing their bit orders to me.
"Reverses the bytes in the given integer value n."
I would expect the description for "byteswap" to be something like "swaps the given bytes of an integer value n." and be called like byteswap(x, a, b), where a and b are the indicies of the bytes to be swapped.
I understand why it's there, but I do find it fun that when many people are trying to reduce undefined behaviour in their code, std::unreachable is literally defined as "this is undefined behaviour, use that to optimise". I suspect 99.9% of uses of std::unreachable would be better replaced by abort. (There will be those times when the code is correct and the optimisation gains are worth it -- but they will be rare).