Odd broken "--date=now" behavior in current git

From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Apr 15, 2015, 04:18 UTC
Message-ID: <CA+55aFxvcN8Dz-t6fi6etycg+AiyR0crXv5AcfCdv8ji-iNBpw@mail.gmail.com>

I just noticed this because I had amended some merge commits with

   git commit --amend --date=now

to update them, and that gets some funny broken timezones. I suspect it's some silly daylight savings time issue.

Lookie here, I can reproduce it trivially with current git (in the git repo itself):

    [torvalds@i7 git]$ date; git commit -m Test --allow-empty --date=now
    Tue Apr 14 21:11:03 PDT 2015
    [master ec7733db5360] Test
     Date: Tue Apr 14 20:11:03 2015 -0800

notice how the commit date message shows something funny. It shows an hour earlier, but in -0800.

And the resulting commit is broken:

    [torvalds@i7 git]$ git show --pretty=fuller
    commit ec7733db5360966434e03eab1a849e6d4227231c (HEAD -> master)
    Author:     Linus Torvalds <torvalds@linux-foundation.org>
    AuthorDate: Tue Apr 14 20:11:03 2015 -0800
    Commit:     Linus Torvalds <torvalds@linux-foundation.org>
    CommitDate: Tue Apr 14 21:11:03 2015 -0700

        Test

notice how the AuthorDate has that "-0800", but the CommitDate has "-0700".

Hmm.

I can't be the only one seeing this? My guess is that there's a missing initialization of tm.tm_isdst somewhere or whatever.

The above is with current git:

    [torvalds@i7 git]$ git version
    git version 2.4.0.rc2

Anybody?

                        Linus