Re: [PATCH] Fix aarch64 PR 99657: ICE with SVE types used without an error

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi Richard,

on 2022/12/7 17:16, Richard Sandiford wrote:
> "Kewen.Lin" <linkw@linux.ibm.com> writes:
>> Hi,
>>
>> In the recent discussion on how to make some built-in type only valid for
>> some target features efficiently[1], Andrew mentioned this patch which he
>> made previously (Thanks!).  I confirmed it can help rs6000 related issue,
>> and noticed PR99657 is still opened, so I think we still want this to
>> be reviewed.
> 
> But does it work for things like:
> 
>     void f(foo_t *x, foo_t *y) { *x = *y; }
> 
> where no variables are being created with foo_t type?
> 

I think it can work for this case as it touches build_indirect_ref.

> That's not to say we shouldn't have the patch.  I'm just not sure
> it can be the complete solution.

I'm not sure about that either, maybe Andrew have more insights.
But as you pointed out in [1], I doubted trying to find all invalid
uses of a built-in type is worthwhile, it seems catching those usual
cases is enough and practical.  So if this verify_type_context
framework can cover the most of uses, maybe it's a good direction
to go and extend.

[1] https://gcc.gnu.org/pipermail/gcc/2022-December/240218.html

BR,
Kewen