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Joined 2 years ago
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Cake day: June 13th, 2023

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  • because with things that the compiler does, like padding for alignment, it frequently takes up more space than that. that was my argument the whole time. what til are you talking about? I’m talking about an extra layer you’ve decided doesn’t count. ofc sizeof bool will be a byte in all of those languages.

    a bool taking up a single byte is a fantasy that those languages use because developers generally don’t need to think about all the other stuff going on.




  • c++ guarantees that calls to malloc are aligned https://en.cppreference.com/w/cpp/memory/c/malloc .

    you can call malloc(1) ofc, but calling malloc_usable_size(malloc(1)) is giving me 24, so it at least allocated 24 bytes for my 1, plus any tracking overhead

    yeah, as I said, in a stack frame. not surprised a compiler packed them into single bytes in the same frame (but I wouldn’t be that surprised the other way either), but the system v abi guarantees at least 4 byte alignment of a stack frame on entering a fn, so if you stored a single bool it’ll get 3+ extra bytes added on the next fn call.

    computers align things. you normally don’t have to think about it. Consider this a TIL moment.