[8u] RFR: 8250636: iso8601_time returns incorrect offset part on MacOS

[Hohensee, Paul]

This looks fine to me, and imo should be done. If the original reviewers had had compatibility concerns, they would have asked for a CSR.

If I had been a reviewer of the original patch, I'd not have worried about log file parsers because (1) the primary (very close to only) GC log producers are developers and production servers, and (2) macOS use for server applications is close to non-existent, and developers can be expected to adapt as needed. Also, the log analyzers I know of don't care about time zone offsets, rather they care about relative timing within intervals of absolute time, and so effectively ignore offsets.

Please post a JDK-8251365 webrev for review. That patch and this one should be pushed together to avoid build breakage.

Thanks,
Paul

On 9/15/20, 11:35 AM, "jdk8u-dev on behalf of Sergey Nazarkin" <jdk8u-dev-retn at openjdk.java.net on behalf of snazarkin at azul.com> wrote:

    Original Bug: https://bugs.openjdk.java.net/browse/JDK-8250636
    Review: https://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2020-July/040894.html

    Please review the backport of the fix for quite specific bug. The fix may be considered as ’too risky to fix’ since changes behavior existed for years.

    It appears Java for BSD-like systems (OSX particularly) prints time in iso8601format (used at GC logs) incorrectly.  Example of confused logs:

    Europe/Moscow (DST isn't in use)
    2020-07-30T11:29:10.350+0300 # Linux
    2020-07-30T11:29:10.350+0300 # Windows
    2020-07-30T11:29:10.350-0300 # MacOS
    Europe/Berlin (DST is in use)
    2020-07-30T10:29:10.350+0200 # Linux
    2020-07-30T10:29:10.350+0200 # Windows
    2020-07-30T10:29:10.350-0100 # MacOS

    The patch is not applied cleanly due to missed context and function signature change.

    Webrev: http://cr.openjdk.java.net/~snazarki/jdk8u-dev-webrev/8250636/

    Unfortunately the change breaks AIX build and additional patch need to be applied:
    https://bugs.openjdk.java.net/browse/JDK-8251365

    Will create new review if this backport is considered as accepted.

    /Sergey