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Re: packed, aligned
On Sun, Feb 11, 2001 at 10:44:05AM +0100, Dennis Bjorklund wrote:
> Some time ago there was a discussion about packed structs and the fact
> that even if you pack a struct, the size of the struct according to
> sizeof() might not be the sum of the size of all the components.
>
> Have I summed it up correctly so far?
No. You can certainly pack a structure such that it has
no padding whatsoever. For example,
struct __attribute__((packed)) bad_struct
{
char c1;
char *cp1;
char c2;
char *cp2;
};
If this does not yield a structure of size (sizeof(char*)*2 + 2)
on any architecture, then it is a bug. It certainly does on my
alpha.
r~