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unwind • today at 11:38 AM • 4 replies • view on HN

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.

Replies

quietbritishjim • today at 12:45 PM

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 • today at 1:36 PM

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.
➕ show 1 reply
Joker_vD • today at 5:16 PM

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.

ErroneousBosh • today at 12:06 PM

> Meta: a space is missing in the title.

I like the word "everybug" :-D