On Mon, 18 Sep 2006, Mark Mitchell wrote:
> Andrew Pinski wrote:
> > The documention on VECTOR_CST is not clear if we can have missing
> > elements in that the remaining elements are zero. Right we produce such
> > VECTOR_CST for things like:
> > #define vector __attribute__((vector_size(16) ))
> > vector int a = {1, 2};
> >
> > But is that valid? We currently produce a VECTOR_CST with just two
> > elements instead of 4. Should we always have the same number of
> > elements in a VECTOR_CST as there are elements in the vector type?
>
> I think it is reasonable for front-ends to elide initializers and to
> follow the usual C semantics that elided initializers are (a) zero, if
> the constant is appearing as an initializer for static storage, or (b)
> unspecified, "random" values elsewhere.
Maybe you didn't mean what I read, but it's not just "for static
storage". By my reading (of the May 6, 2005 ISO/IEC 9899:TC2
for reference), all items in arrays and named structure members
not mentioned in the initializer should be 0-initialized (the
"all subobjects that are not initialized explicitly shall be
initialized implicitly the same as objects that have static
storage duration" part in 6.7.8:19).
brgds, H-P
