Re: [Patch] Fortran: Avoid var initialization in interfaces [PR54753]

[Harald Anlauf <anlauf@gmx.de>]

Hi Tobias,

Am 02.10.21 um 20:29 schrieb Tobias Burnus:
> On 02.10.21 20:01, Sandra Loosemore wrote:
>> On 9/29/21 2:53 AM, Tobias Burnus wrote:
>>> There are three issues, this patch solves the first:
>>> * reject-valid issue due to adding the initializer also to a dummy
>>>    argument which is in an INTERFACE block. Having initializers in
>>>    INTERFACE blocks is pointless and causes for the attached testcase
>>    the bogus error:
>>>    "Assumed-rank variable y at (1) may only be used as actual argument"
>>> ...
>> This has indeed allowed me to make progress on adding the diagnostic, 
>> but I'm seeing some test regressions on x86_64-linux-gnu that are due 
>> to this patch alone:
>>
>> FAIL: gfortran.dg/default_initialization_3.f90   -O0  execution test
> 
> I do not see this error. Can you double check that you indeed use the 
> posted patch:
> 
> https://gcc.gnu.org/pipermail/gcc-patches/2021-September/580483.html – 
> and nothing else, e.g., an earlier draft?

Sandra is right.  Actually I do see that regression, too.
The default initialization is missing in F1, see dump-tree:

__attribute__((fn spec (". R w w ")))
integer(kind=4) master.0.f1 (integer(kind=8) __entry, struct t1 * d2, 
struct t1 * d1)
{
   integer(kind=4) res;
   integer(kind=4) __result_master.0.f1;
   integer(kind=4) res.0 [value-expr: __result_master.0.f1];

   if (d1 != 0B)
     {
       {
         struct t1 t1.1;

         t1.1.i = 7;
         *d1 = t1.1;
       }
     }

The latter "if (d1 != 0B)" block gets removed by your change, and
this is not good.

> (I still have to commit it; it was approved by Harald, but he also he 
> preferred to have a second view, I decided to wait until tomorrow/Monday 
> before committing it.)

Well, I did not regtest, only read the patch and trust that you did your
homework!

> Tobias

Harald