On Sat, Dec 06, 2025 at 11:17:11AM +0100, Richard Biener wrote:
> > The following testcase ICEs since checking has been added to TYPE_PRECISION
> > macro. check_bitfield_type_and_width is called when attributes haven't
> > been applied to the bit-field decl yet and so it still has INTEGER_TYPE
> > type, while at finish_struct time it already has VECTOR_TYPE.
> >
> > The following patch just repeats the check_bitfield_type_and_width
> > in there.
> >
> > Another option would be let handle_vector_size_attribute check for
> > bit-fields and error out there.
>
> I think we try to do that there but 8 bits of precision fail to be catched?
Nothing checks it there. The C FE does the checking before applying
the attributes and updates the type to the width precision only
in finish_struct after that happens.
struct S { int : 7 __attribute__((vector_size (32))); };
ICEs the same way.
Though, I think the C++ FE applies the attributes before the checking,
and DECL_INITIAL on FIELD_DECLs means there something completely different
(NSDMI).
Jakub
