JDK 17: First Release Candidate

[David Holmes]

On 16/08/2021 7:50 pm, Florian Weimer wrote:
> * David Holmes:
> 
>>>> That seems like a glibc bug to me as SIGSTKSZ is supposed to be a constant.
> 
>>> It is still a constant in glibc's POSIX mode, but OpenJDK does not
>>> use POSIX mode (with good reason).
>>
>> Can you elaborate on what that good reason is please? If this is
>> something critical then it really needs to be documented somewhere. It
>> makes me uncomfortable that we have spent a lot of time cleaning up
>> hotspot runtime code to provide shared "posix" implementations, if we
>> may not even be getting Posix semantics.
> 
> glibc's POSIX mode removes all declarations and definitions from its
> header files which are not part of the requested POSIX version (at least
> in theory; there are of course bugs).  This is based on what is in the
> actual standard, not on what typical implementations support.
> 
> For example, the functions lseek64 and ftruncate64 are used in
> src/hotspot/os/posix/os_posix.cpp but are not part of any POSIX version.
> gethostbyname is no longer part of POSIX, either.

Ah I see - thanks for the explanation Florian! I'll see where we 
can/should document this.

David

> Thanks,
> Florian
>