RFR: Use isnan instead of isnanf

[David Holmes]

On 12/04/2017 7:52 PM, Magnus Ihse Bursie wrote:
> On 2017-04-12 02:30, David Holmes wrote:
>> Hi Mikael,
>>
>> On 12/04/2017 9:04 AM, Mikael Vidstedt wrote:
>>>
>>> isnanf is not available in musl. posix says that isnan handles both
>>> float and double arguments (typically through a macro checking the
>>> size of the operand and delegation to the corresponding/actual isnan
>>> primitive).
>>>
>>> This change makes the two JDK wrapper macros call isnan instead of
>>> isnanf. I’ve tried to verify that the toolchains I have access to
>>> does the Right(tm) thing for float, but additional
>>> verification/testing is probably warranted before this is “productized”.
>>>
>>> hotspot:
>>> http://cr.openjdk.java.net/~mikael/webrevs/portola/isnan/webrev.00/hotspot/webrev/
>>> jdk:
>>> http://cr.openjdk.java.net/~mikael/webrevs/portola/isnan/webrev.00/jdk/webrev/
>>
>> Are we building with C99 support enabled?
> No, we are not. In fact, on Solaris, we build with c99 explicitly off.

So can someone explain to me how we are able to use these math 
functions/macros that seem to be guarded with:

#ifdef __USE_ISOC99

??

David
-----

> We probably *should* move to C99 in JDK 10, but that is (perhaps?)
> another story.
>
> /Magnus
>>
>> The feature test macros are shown as:
>>
>> isnan():
>>   _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE ||
>> _POSIX_C_SOURCE >= 200112L;
>>   or cc -std=c99
>>
>> isnanf(), isnanl():
>>   _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600
>>
>> On linux we don't seem to do anything to explicitly enable access to
>> either of these ??
>>
>> Thanks,
>> David
>>
>>> Cheers,
>>> Mikael
>>>
>