On Mon, Dec 28, 2020 at 04:17:36PM +0000, Ramsay Jones wrote:
>
>
> On 26/12/2020 17:51, Luc Van Oostenryck wrote:
> > Currently, packed structs are not handled correctly.
> >
> > Add some testcases for them.
> >
> > Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
> > ---
> > validation/packed-deref0.c | 24 ++++++++++++++++++++++++
> > validation/packed-struct.c | 33 +++++++++++++++++++++++++++++++++
> > 2 files changed, 57 insertions(+)
> > create mode 100644 validation/packed-deref0.c
> > create mode 100644 validation/packed-struct.c
> >
> > diff --git a/validation/packed-deref0.c b/validation/packed-deref0.c
> > new file mode 100644
> > index 000000000000..865ad68a4f37
> > --- /dev/null
> > +++ b/validation/packed-deref0.c
> > @@ -0,0 +1,24 @@
> > +#define __packed __attribute__((packed))
> > +
> > +typedef struct {
> > + __INT8_TYPE__ a;
> > + __INT16_TYPE__ b;
> > + __INT32_TYPE__ c;
> > +} __packed obj_t;
> > +
> > +_Static_assert(sizeof(obj_t) == 7, "sizeof packed struct");
> > +
> > +static void foo(obj_t *ptr, int val)
> > +{
> > + ptr->c = val;
> > +}
> > +
> > +static void bar(obj_t o)
> > +{
> > + foo(&o, 0);
> > +}
> > +
> > +/*
> > + * check-name: packed-deref0
> > + * check-known-to-fail
> > + */
> > diff --git a/validation/packed-struct.c b/validation/packed-struct.c
> > new file mode 100644
> > index 000000000000..5039be4d0b45
> > --- /dev/null
> > +++ b/validation/packed-struct.c
> > @@ -0,0 +1,33 @@
> > +#define __packed __attribute__((packed))
> > +
> > +typedef unsigned char u8;
> > +typedef __UINT16_TYPE__ u16;
> > +typedef __UINT32_TYPE__ u32;
> > +typedef __UINT64_TYPE__ u64;
> > +
> > +struct a {
> > + u8 a;
> > + u8 b;
> > + u16 c;
> > +} __packed;
> > +_Static_assert(__alignof(struct a) == 1, "align struct");
> > +_Static_assert( sizeof(struct a) == sizeof(u32), " size struct");
>
> Hmm, I don't think '== sizeof(u32)' is any better than '== 4'.
Yes, I agree.
-- Luc
