RFR: 8200203: Missing platform definitions for ia64

[David Holmes]

On 26/03/2018 11:06 AM, John Paul Adrian Glaubitz wrote:
> On 03/26/2018 08:08 AM, David Holmes wrote:
>> Everytime I see these zero-only platform definitions it makes we think we really
>> should have these isolated into a zero-specific file. At the moment this can
>> paint a false picture that all these platforms have full OpenJDK ports available.
> 
> Is that really the case though? If someone is reading the platform.m4 file, they
> might think that but simply trying to build the server variant for ia64 would
> fail very quickly anyway and people would realize it's not supported.

It's not so much that (though there have been cases!) but people just 
looking in that file can't tell a full platform from a zero-only 
platform. The general rule is that OpenJDK doesn't accept platform 
specific patches unless there is a fully supported port of that 
platform. But zero is the exception to that rule. So I just think, as a 
separate RFE, it would be good to split these out into platforms-zero.m4 
which can then be included in platforms.m4

> In the end, I think the extended portability OpenJDK highly outweighs your
> reservations above. Someone who doesn't understand the difference between Zero
> and the official ports, is also unlikely to try building OpenJDK from source
> themselves.
> 
>> I also wonder if the values here can be reliably obtained via uname/sysconf
>> or some such utility so that we don't have to list every single platform
>> individually?
> 
> I think autoconf normally has support for this, yes. It's rather unusual
> having to add targets manually. But you will need the mapping to VAR_CPU,
> for example. I will have a look at it anyway.
> 
> For the time being, it would be nice if I can get this and a second follow-up
> change for ia64 merged so downstream (currently Debian and Gentoo for ia64)
> doesn't have to carry any additional patches anymore.

I don't have a concern with this going in as-is for now. But wait for 
Magnus or Erik to give the okay.

Thanks,
David

> Thanks,
> Adrian
>