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Comment by unwind

8 hours ago

Meta: a space is missing in the title.

Since this is one of the bugs, I always recommemd writing

    game->boardPieces = swAlloc(sizeof(ThingHandle*) * row * column);

Like this instead:

    game->boardPieces = swAlloc(sizeof *game->boardPieces * row * column);

It's not 100% better, but it cuts out a few tokens which helps readability and moves the significant asterix further left where I think it's easier to spot.

6 comments

unwind

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quietbritishjim  6 hours ago

Honestly, I think I'm more likely to get your form wrong than the original one. This doesn't obviously look wrong to me:

   game->boardPieces = swAlloc(sizeof game->boardPieces * row * column);

Maybe I find this harder to parse because I'm not used to sizeof without brackets (though I know it's valid). But I think the bigger deal is that your version has a bug if the star is missing whereas there's has a bug if the star is present; it's easier to spot something extra than it is to spot something missing.

jstimpfle  6 hours ago

It's totally true, using sizeof like a function is one of my pet peeves. Even the kernel people do it but it's WRONG and you are right.

But ACSHUALLY, how you write allocation is like this

    #define sane_alloc(type, count) ((type *) malloc(sizeof (type) * (count)))

    game->boardPieces = sane_alloc(BoardPiece, row * column);

The kernel people seem to finally have figured out this one in 2026.

  • DonHopkins  2 hours ago

    Nothing is sane in a language that lets you say 4["Foo!"]

    Array indexing in C is just pointer arithmetic wearing Groucho Marx Glasses.

    C combines the flexibility and power of assembly language with the user-friendliness of assembly language.

    • jstimpfle  29 minutes ago

      > Nothing is sane in a language that lets you say 4["Foo!"]

      I just had a look at your HN profile page and was struck by the irony of seeing your Forth vs Lisp vs Postscript code examples there. Now consider that I've never written code like 4["Foo!"], even though I know it's possible, but in other languages you constantly have to do mental gymnastics to get any real work done, and those are allegedly so much saner !???

Joker_vD  2 hours ago

Frankly, "sizeof(T*)" should generate a warning if T is anything other than void, or a function type.

Yes, I know that C technically allows rather heterogenous representations for pointers to different types, but in practice there is difference only between object pointers and function pointers.