[8u] [RFR] Request for Review of Backport of JDK-8179887: Build failure with glibc >= 2.24: error: 'int readdir_r(DIR*, dirent*, dirent**)' is deprecated

[David Holmes]

On 8/07/2018 8:25 PM, B. Blaser wrote:
> On 6 July 2018 at 20:50, Andrew Hughes <gnu.andrew at redhat.com> wrote:
>> On 6 July 2018 at 02:31, David Holmes <david.holmes at oracle.com> wrote:
>>
>> snip...
>>
>>>
>>>
>>> There's no JFR in the open in 8u, but I would expect this to still cause the
>>> same problem for Oracle's 8u JDK.
>>>
>>
>> Ok, there's not really much I can do to test this then?
>>
>>
>> snip...
>>
>>>>
>>>>> I'd be inclined to disable the build warning for 8u rather than make code
>>>>> changes (which will likely still break JFR).
>>>>
>>>>
>>>> This was my first inclination - and it's what we went with for OpenJDK
>>>> 7 [0] [1] -
>>>> but it brings its own problems. The way it was disabled at first uses
>>>> inline
>>>> pragmas that don't work with older versions of GCC that are used to build
>>>> 8. Moving the pragma outside the function is problematic because this is
>>>> an
>>>> inline header file.
>>>
>>>
>>> It's never easy is it. :(
>>>
>>
>> Shall I propose this fix instead then?
> 
> Note that I also provided a variant of the fix only in 'os::readdir'
> which shouldn't break JFR:
> 
> https://bugs.openjdk.java.net/secure/attachment/76645/os_readdir2.patch
> 
> Maybe this could make it for 8u?

This is linux specific code but it seems to be using internal knowledge 
of how a struct dirent is laid out on Linux. I'd also have to ensure 
this gets tested with JFR on 8u.

I'll leave it to Andrew to decide on the above fix, or the makefile 
warning fix. I'll Review whichever is chosen.

Thanks,
David

> Bernard
> 
> 
>>> Cheers,
>>> David
>>>
>>>
>>>>>
>>>>> David
>>>>>
>>>>>
>>>>
>>>> [0] http://hg.openjdk.java.net/jdk7u/jdk7u/hotspot/rev/66e04addced6
>>>> [1] http://hg.openjdk.java.net/jdk7u/jdk7u/hotspot/rev/819d329e1fd0
>>>>
>>>
>>
>>
>>
>> --
>> Andrew :)
>>
>> Senior Free Java Software Engineer
>> Red Hat, Inc. (http://www.redhat.com)
>>
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