Re: Generic private type declaration

["Alejandro R. Mosteo" <alejandro@mosteo.com>]

On 26/11/16 20:18, Tero Koskinen wrote:
> 26.11.2016, 10.45, Jacob Sparre Andersen wrote:
>> Alejandro R. Mosteo wrote:
>>
>>> I get in both gnat 4.9.3 and gpl2016 the following error:
>>>
>>> b001_tagged.adb:15:04: instantiation error at line 7
>>> b001_tagged.adb:15:04: type derived from tagged type must have extension
>>> gnatmake: "b001_tagged.adb" compilation error
> ...
>> I suspect that this is an error due to how GNAT expands generics.  It
>> might be useful to try to see how Janus/Ada and ICC/Ada treats it.  If I
>> remember correctly, Janus/Ada implements generics differently from GNAT.
>
> Janus/Ada 3.1.2c result here, just a warning on line 13:
> Input File Is C:\Work\mosteo-generic\B001_TAGGED.ADB
> Pass II
> Expected J2inst duplication to be the same
>
>
> In File C:\Work\mosteo-generic\B001_TAGGED.ADB(13)
> --------------
>    12:
>    13:     type Void is tagged null record;
> ----------------^
> *WARNING* Construct allowed only in a package specification (6.4.9)
> Expected J2inst duplication to be the same
> Bad or locked TREEFLAG.IN file -- see J3Tree_Debug
> Pass III - JCode
> Pass IV - 80386 Family
> Creating C:\Work\mosteo-generic\B001_TAG.SRL
> Thank You For Using JANUS/Ada
> (...)

Thanks to everyone that answered/took the time to test.

So, to summarize: Janus/Ada accepts it, Gnat does not, and some other 
compiler used by G.B. also rejects it.

Cheers,
Alex.

>
>>
>> Greetings,
>>
>> Jacob
>>
>
> Yours,
>  Tero
>