[PATCH] fix zero builds for "unknown" architectures

[David Holmes]

Hi Coleen,

This looks right to me now. For the record though there should be a RFR 
email with the bug id etc.

Thanks,
David

On 10/09/2015 1:12 PM, Coleen Phillimore wrote:
>
> David pointed out to me offline that the order of ARM conditionals are
> incorrect, because AARCH64 is a special ARM so I've reversed them:
>
> +#if defined(AMD64)
> +  strncpy(cpuinfo, "x86_64", length);
> +#elif defined(IA32)
> +  strncpy(cpuinfo, "x86_32", length);
> +#elif defined(IA64)
> +  strncpy(cpuinfo, "IA64", length);
> +#elif defined(SPARC)
> +  strncpy(cpuinfo, "sparcv9", length);
> +#elif defined(AARCH64)
> +  strncpy(cpuinfo, "AArch64", length);
> +#elif defined(ARM)
> +  strncpy(cpuinfo, "ARM", length);
> +#elif defined(PPC)
> +  strncpy(cpuinfo, "PPC64", length);
> +#elif defined(ZERO_LIBARCH)
> +  strncpy(cpuinfo, ZERO_LIBARCH, length);
> +#else
> +  strncpy(cpuinfo, "unknown", length);
> +#endif
>
> Does this look right?
>
> Thanks,
> Coleen
>
> On 9/9/15 9:42 PM, Coleen Phillimore wrote:
>>
>>
>> On 9/9/15 7:59 PM, David Holmes wrote:
>>> On 10/09/2015 2:56 AM, Coleen Phillimore wrote:
>>>>
>>>> I think I like patch #1 better.   I will sponsor it and make sure it
>>>> works on my machine.   Thank you for fixing this on the other
>>>> platforms.
>>>
>>> I think there should be a way to detect an unknown arch via the build
>>> mechanics. I would think an unknown arch would also impact includes
>>> of <os>_<arch> headers ... unless the "arch" is Zero in that case? In
>>> which case maybe we should be checking for Zero here?
>>>
>>> Also need to check the ARM versus ARM32 - as with PPC/PPC32/PPC64 I
>>> think plain ARM means 32-bit or 64-bit, but Aarch64 covers 64-bit.
>>
>> I'm not sure what this comment means.   The code does check ARM, but
>> it doesn't have specific PPC checks for 32 and 64 bit.  I think the
>> PPC people verified this change works for them.
>>
>> +#if defined(AMD64)
>> +  strncpy(cpuinfo, "x86_64", length);
>> +#elif defined(IA32)
>> +  strncpy(cpuinfo, "x86_32", length);
>> +#elif defined(IA64)
>> +  strncpy(cpuinfo, "IA64", length);
>> +#elif defined(SPARC)
>> +  strncpy(cpuinfo, "sparcv9", length);
>> +#elif defined(ARM)
>> +  strncpy(cpuinfo, "ARM", length);
>> +#elif defined(AARCH64)
>> +  strncpy(cpuinfo, "AArch64", length);
>> +#elif defined(PPC)
>> +  strncpy(cpuinfo, "PPC64", length);
>> +#elif defined(ZERO_LIBARCH)
>> +  strncpy(cpuinfo, ZERO_LIBARCH, length);
>> +#else
>> +  strncpy(cpuinfo, "unknown", length);
>> +#endif
>>
>> And your other mail suggests a default case, which both of the parts
>> of Matthias's patch has.
>>
>> I was in the process of checking this in under the small change only
>> needs one reviewer rule.
>>
>> Coleen
>>>
>>> David
>>>
>>>> Coleen
>>>>
>>>> On 9/9/15 12:19 PM, Matthias Klose wrote:
>>>>> seen with jdk9 / tag jdk9-b80.  zero builds which don't match one of
>>>>> the hotspot
>>>>> architectures fail to build in src/os/linux/vm/os_linux.cpp, because
>>>>> there is no
>>>>> default / or else clause:
>>>>>
>>>>> const char* search_string = IA32_ONLY("model name") AMD64_ONLY("model
>>>>> name")
>>>>>                              IA64_ONLY("") SPARC_ONLY("cpu")
>>>>>                              ARM32_ONLY("Processor")
>>>>> PPC_ONLY("Processor")
>>>>> AARCH64_ONLY("Processor");
>>>>>
>>>>> and:
>>>>>
>>>>>    strncpy(cpuinfo, IA32_ONLY("x86_32") AMD64_ONLY("x86_32")
>>>>>                     IA64_ONLY("IA64") SPARC_ONLY("sparcv9")
>>>>>                     ARM32_ONLY("ARM") PPC_ONLY("PPC64")
>>>>> AARCH64_ONLY("AArch64"),
>>>>> length);
>>>>>
>>>>> attached are two alternate patches how to fix this, either by not
>>>>> using the
>>>>> *_ONLY macros, or by defining an UNKOWN_ARCH_ONLY macro.
>>>>>
>>>>> Two other issues:
>>>>>   - The zero builds only define ARM, not ARM32, so the clause
>>>>>     should be ARM_ONLY (or at least an ARM_ONLY added).
>>>>>   - The cpuinfo string seems to be wrong for AMD64_ONLY.
>>>>>
>>>>> Verified that zero builds without errors with on of these patches.
>>>>>
>>>>> Attaching both patches.
>>>>>
>>>>>    Matthias
>>>>>
>>>>
>>
>