Luigi Mantellini wrote:
Dear All
From my point of view, when packing is formally required (ie packets headers), the structs should be declared explicitly as __packed__. The correctness of the object code should be independent from the compiler optimizations and we should always remember that the offset of a struct field is not necessarily the sum of the sizes of the fields that precede it.
struct { type1 a; type2 b; type3 c; } mystruct
offset(mystruct.c) != sizeof(type1) + sizeof(type2).
Regarding the CFLAGS used by me... I haven't set any CFLAGS and I just do a make qemu_mips_config CROSS_COMPILE=mips-linux- && make CROSS_COMPILE=mips-linux... and a boundary alignment is not an alien choice for a good compiler (a standard gcc4.2.4 in my case). Furthermore I expect a correct object always... with any -Ox flag (a apart bugs... of course).
My idea should be to declare a define like this
#define PKT_HEADER __attribute__((__packed__))
my 2EuroCents.
best regards,
luigi
OK, sounds good. Send a patch please.
regards, Ben <snip>