Re: [PATCH v2] fortran: Detect duplicate unlimited polymorphic types [PR103662]

[Harald Anlauf <anlauf@gmx.de>]

Hi Mikael,

Am 22.04.22 um 12:53 schrieb Mikael Morin:
> Le 21/04/2022 à 23:14, Mikael Morin a écrit :
>> Hello,
>>
>> this is a fix for PR103662, a TBAA issue with unlimited polymorphic
>> types.
>>
>> I attached a draft patch to the PR which was accumulating all unlimited
>> polymorphic symbols to a single namespace, avoiding duplicate symbols
>> and thus eliminating the problem.
>>
>> After reviewing the code more in detail, I was afraid that some symbols
>> could still end up in the local namespace, and that the problem would
>> remain for them after all.
>>
>> Despite not being able to generate a testcase where it happened, I
>> decided to produce a patch based on Jakub’s analysis in the PR audit
>> trail, as that way supports duplicates by design.
>>
>> On top of Jakub’s patch, there are a couple more types registrations
>> just in case (they handle duplicates so that’s fine), and the type
>> comparison fix that he was too fortran-uncomfortable to do.
>>
>> The testcase had to be fixed as we found out in the PR audit trail.
>>
>> Regression tested on x86_64-pc-linux-gnu. OK for master?
>>
>> Mikael
>
> I have read Jakub’s analysis again, and it says the type registration is
> useless for unlimited polymorphic fake symbols, as they are all
> translated as ptr_type_node.
> So it can be dropped, which brings this v2 patch closer to Jakub’s
> original.
>
> Regression tested again. OK?

LGTM.

Thanks for the patch!

Harald