RFR: JDK-8165158: Fix zero builds for non-listed architectures

[Erik Joelsson]

Sponsoring the suggested patch.

Matthias, could you verify that I got it right and that it works for 
you? I don't have a setup where I can test such a platform.

Webrev: http://cr.openjdk.java.net/~erikj/8165158/webrev.01/

Bug: https://bugs.openjdk.java.net/browse/JDK-8165158

/Erik

On 2016-08-31 16:36, Erik Joelsson wrote:
> Hello,
>
> I think the second one is better. Is there a bug filed for this?
>
> /Erik
>
>
> On 2016-08-30 14:33, Matthias Klose wrote:
>> The zero build for architectures not explicitly listed fails 
>> currently in
>> hotspot, because of an unset macro, and the compiler complains about 
>> a single -D
>> option passed.
>>
>> Here are two proposals how to fix these:
>>
>>   - Not passing the -D<cpu_define> if it is not set. Afaik the define
>>     is only used for hotspot builds, not for zero builds.
>>
>>   - Provide a fall back for "unknown" zero architectures.
>>
>> Matthias
>