• mmddmm@lemm.ee
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      7 days ago

      And compiler. And hardware architecture. And optimization flags.

      As usual, it’s some developer that knows little enough to think the walls they see around enclose the entire world.

      • Lucien [he/him]@mander.xyz
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        7 days ago

        Fucking lol at the downvoters haha that second sentence must have rubbed them the wrong way for being too accurate.

      • timhh@programming.dev
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        6 days ago

        I don’t think so. Apart from dynamically typed languages which need to store the type with the value, it’s always 1 byte, and that doesn’t depend on architecture (excluding ancient or exotic architectures) or optimisation flags.

        Which language/architecture/flags would not store a bool in 1 byte?

        • brian@programming.dev
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          6 days ago

          things that store it as word size for alignment purposes (most common afaik), things that pack multiple books into one byte (normally only things like bool sequences/structs), etc

          • timhh@programming.dev
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            2 days ago

            things that store it as word size for alignment purposes

            Nope. bools only need to be naturally aligned, so 1 byte.

            If you do

            struct SomeBools {
              bool a;
              bool b;
              bool c;
              bool d;
            };
            

            its 4 bytes.

            • brian@programming.dev
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              2 days ago

              sure, but if you have a single bool in a stack frame it’s probably going to be more than a byte. on the heap definitely more than a byte

              • timhh@programming.dev
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                15 hours ago

                but if you have a single bool in a stack frame it’s probably going to be more than a byte.

                Nope. - if you can’t read RISC-V assembly, look at these lines

                        sb      a5,-17(s0)
                ...
                        sb      a5,-18(s0)
                ...
                        sb      a5,-19(s0)
                ...
                

                That is it storing the bools in single bytes. Also I only used RISC-V because I’m way more familiar with it than x86, but it will do the same thing.

                on the heap definitely more than a byte

                Nope, you can happily malloc(1) and store a bool in it, or malloc(4) and store 4 bools in it. A bool is 1 byte. Consider this a TIL moment.

        • mmddmm@lemm.ee
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          6 days ago

          Apart from dynamically typed languages which need to store the type with the value

          You know that depending on what your code does, the same C that people are talking upthread doesn’t even need to allocate memory to store a variable, right?

            • timhh@programming.dev
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              2 days ago

              I think he’s talking about if a variable only exists in registers. In which case it is the size of a register. But that’s true of everything that gets put in registers. You wouldn’t say uint16_t is word-sized because at some point it gets put into a word-sized register. That’s dumb.