On 2018-03-26 03:06, 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.
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 agree. I don't think it's a problem that we list the zero platforms in
platform.m4.
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.
You can consider platform.m4 (amongst other thing) to be a "translation"
between whatever autoconf calls a platform, and what OpenJDK has
traditionally used. For some platforms, this is a no-brainer, but for
other, there are unfortunately multiple, well-accepted names (amd64,
x86_64, x64), and the choice OpenJDK made in the past was not always
aligned with the uname/sysconf/autoconf name.
Despite our best efforts, we are still plagued by having different names
in different places.
We could perhaps try to make a "generic" section that maps OpenJDK names
and values directly to what's given by the system, and use it whereever
it applies. I'm not sure how to extract the endianness, though..
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.
Your patch looks good to me.
/Magnus
Thanks,
Adrian
