On 2020-05-11 17:25, Jan Lahoda wrote:
Thanks Magnus for the SOURCE_DATE_EPOCH!
I've adjusted the patch to use it:
http://cr.openjdk.java.net/~jlahoda/8241616/webrev.01/
It also explicitly sets the output of TransitiveDependencies on the
command line (before it was passing just the directory into which the
file was written). Also should resolve the suspicious timestamp code
noted by Alan, by removing the code altogether, as we can use the
timestamp provided by the build.
Looks good to me!
The ct.sym will now be reproducible only if the --with-source-date
option is used. I wonder why at least "current" is not the default -
that would probably make testing reproducible builds much easier.
That was my original intention, but after working with the patch I grew
wary. Other tools might pick up SOURCE_DATE_EPOCH and without more
testing on different platforms I would rather have the default something
that mimics the old behavior.
/Magnus
How does this look?
Thanks,
Jan
On 07. 05. 20 17:48, Magnus Ihse Bursie wrote:
On 2020-04-30 14:50, Jan Lahoda wrote:
On 30. 04. 20 14:29, Magnus Ihse Bursie wrote:
On 2020-04-30 12:41, Alan Bateman wrote:
On 30/04/2020 08:03, Jan Lahoda wrote:
Hi,
The building of lib/ct.sym is not reproducible, due to timestamps
of files inside the file (which is basically a zip file).
The proposed solution is to use a constant timestamp for the
files inside the ct.sym file. To simplify the construction, the
CreateSymbols tool does not produce files on the filesystem
anymore, but rather constructs the ct.sym directly.
Proposed webrev:
http://cr.openjdk.java.net/~jlahoda/8241616/webrev.00/
JBS: https://bugs.openjdk.java.net/browse/JDK-8241616
1587656816359 = 2020-04-23T15:46:56.359Z. Is there anything
significant with this timestamp? Magnus might have suggestions but
maybe it would be saner to pick up the value of DEFAULT_VERSION_DATE.
There is an officially suggested standard, SOURCE_DATE_EPOCH for
reproducible builds. [1] I have long-term vision to include this in
the entire JDK build, but has of yet not even started on that. :-(
This might be a good first step to start using it. I can assist in
making the needed makefile changes to have that environment
variable available.
I think a standard mechanism would be great. I don't think this
patch is very urgent, so I am happy to wait some time (rather than
add a timestamp to symbols and then remove it when there's a
standard mechanism).
JDK-8244592 is now in mainline, and you can start relying on
SOURCE_DATE_EPOCH being present in the environment when building.
/Magnus
Thanks,
Jan
/Magnus
[1] https://reproducible-builds.org/specs/source-date-epoch/
There is some curious code that generates the timestamp with:
Long.toString(FileTime.from(Instant.now()).toMillis())
Could this use Instant.now().toEpochMilli() instead?
-Alan
