On Tue, 18 Nov 2025, Qing Zhao wrote:
> At the same time, shall we support the following with -fms-extensions:
>
> /* -fms-extensions */
>
> struct ids
> {
> int length_ad;
> int length_na;
> };
>
> struct person
> {
> int age;
> int weight;
> struct ids; // Anonymous structure, no name needed
> char *address __attribute__ ((counted_by (length_ad)));
> char name[] __attribute__ ((counted_by (length_na)));
> } *Jim;
>
> i.e, in the above, the counted_by fields for Pointer “address” and FAM “name”
> are in the anonymous
> structure “struct ids” which is not inlined into the “struct person”.
>
> Any idea on this?
Yes, supporting such outward-to-inward counted_by references makes sense
in a way that inward-to-outward references don't (because checking the
validity of outward-to-inward references doesn't depend on anything
unknown at the end of the structure definition).
--
Joseph S. Myers
[email protected]
