Re: [V7][PATCH 1/2] Handle component_ref to a structre/union field including flexible array member [PR101832]

[Qing Zhao <qing.zhao@oracle.com>]

> On May 25, 2023, at 1:41 AM, Bernhard Reutner-Fischer <rep.dot.nop@gmail.com> wrote:
> 
> On 24 May 2023 16:09:21 CEST, Qing Zhao <qing.zhao@oracle.com> wrote:
>> Bernhard,
>> 
>> Thanks a lot for your comments.
>> 
>>> On May 19, 2023, at 7:11 PM, Bernhard Reutner-Fischer <rep.dot.nop@gmail.com> wrote:
>>> 
>>> On Fri, 19 May 2023 20:49:47 +0000
>>> Qing Zhao via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
>>> 
>>>> GCC extension accepts the case when a struct with a flexible array member
>>>> is embedded into another struct or union (possibly recursively).
>>> 
>>> Do you mean TYPE_TRAILING_FLEXARRAY()?
>> 
>> The following might be more accurate description:
>> 
>> GCC extension accepts the case when a struct with a flexible array member
>> is embedded into another struct or union (possibly recursively) as the last field.
>> 
>> 
>> 
>>> 
>>>> diff --git a/gcc/tree.h b/gcc/tree.h
>>>> index 0b72663e6a1..237644e788e 100644
>>>> --- a/gcc/tree.h
>>>> +++ b/gcc/tree.h
>>>> @@ -786,7 +786,12 @@ extern void omp_clause_range_check_failed (const_tree, const char *, int,
>>>>   (...) prototype, where arguments can be accessed with va_start and
>>>>   va_arg), as opposed to an unprototyped function.  */
>>>> #define TYPE_NO_NAMED_ARGS_STDARG_P(NODE) \
>>>> -  (TYPE_CHECK (NODE)->type_common.no_named_args_stdarg_p)
>>>> +  (FUNC_OR_METHOD_CHECK (NODE)->type_common.no_named_args_stdarg_p)
>>>> +
>>>> +/* True if this RECORD_TYPE or UNION_TYPE includes a flexible array member
>>>> +   at the last field recursively.  */
>>>> +#define TYPE_INCLUDE_FLEXARRAY(NODE) \
>>>> +  (RECORD_OR_UNION_CHECK (NODE)->type_common.no_named_args_stdarg_p)
>>> 
>>> Until i read the description above i read TYPE_INCLUDE_FLEXARRAY as an
>>> option to include or not include something. The description hints more
>>> at TYPE_INCLUDES_FLEXARRAY (with an S) to be a type which has at least
>>> one member which has a trailing flexible array or which itself has a
>>> trailing flexible array.
>> 
>> Yes, TYPE_INCLUDES_FLEXARRAY (maybe with a S is a better name) means the structure/union TYPE includes a flexible array member or includes a struct with a flexible array member as the last field.
>> 
> 
> So ANY_TRAILING_FLEXARRAY or TYPE_CONTAINS_FLEXARRAY, TYPE_INCLUDES_FLEXARRAY or something like that would be more clear, i don't know.
> I'd probably use the first, but that's enough bike shedding for me now. Let's see what others think.

Thanks. I changed it to TYPE_INCLUDES_FLEXARRAY.

Qing
> 
> thanks,
> 
>> Hope this is clear.
>> thanks.
>> 
>> Qing
>>> 
>>>> 
>>>> /* In an IDENTIFIER_NODE, this means that assemble_name was called with
>>>>   this string as an argument.  */