> On Jun 28, 2022, at 2:22 PM, Jakub Jelinek <ja...@redhat.com> wrote:
>
> On Tue, Jun 28, 2022 at 06:15:58PM +0000, Qing Zhao wrote:
>>> Because the flag just tells whether some array shouldn't be treated as
>>> (poor man's)
>>> flexible array member. We still need to find out if some FIELD_DECL is to
>>> be treated like a flexible array member, which is a minority of
>>> COMPONENT_REFs.
>>> struct S { int a; char b[0]; int c; } s;
>>> struct T { int d; char e[]; };
>>> struct U { int f; struct T g; int h; } u;
>>> Neither s.b nor u.g.e is to be treated like flexible array member,
>>> no matter what -fstrict-flex-array= option is used.
>>
>> Then, to resolve this issue, we might need a opposite flag
>> DECL_IS_FLEXARRAY in FIELD_DECL?
>>
>> The default is FALSE for all FIELD_DECL.
>
> Doesn't matter whether it is positive or negative, you still need to analyze
> it. See the above example. If you have struct T t; and test t.e, then it
> is flexarray. But u.g.e is not, even when the COMPONENT_REF refers to the
> same FIELD_DECL. In the t.e case e is the very last field, in the latter
> case u.g.e is the last field in struct T, but struct U has the h field after
So, do you mean that the current FE analysis will not be able to decide whether
a specific array field is at the end of the enclosing structure?
Only the middle end can decide this ?
Qing
> it.
>
> Jakub
>
