DR-i#1565: use a future date for VERSION_NUMBER_PATCHLEVEL on git log failure

Commit log for first patchset:
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DR-i#1565: use a future date for VERSION_NUMBER_PATCHLEVEL on git log failure

We use a future date for VERSION_NUMBER_PATCHLEVEL instead of fatal
error on git log failure.
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[zhaoqin, 2016-04-04 21:20:51]

Commit log for latest patchset:
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DR-i#1565: set VERSION_NUMBER_PATCHLEVEL even on git log failure

We try different ways to set VERSION_NUMBER_PATCHLEVEL on git log failure.

Review-URL: https://codereview.appspot.com/289680043
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[bruening, 2016-04-04 21:26:22]

LGTM w/ comments

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt
File CMakeLists.txt (right):

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode184
CMakeLists.txt:184: # We want the committer date (not author date) (xref
i#1565).  We request UNIX
Shouldn't the DR stay there?  This is a DrM file.

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode186
CMakeLists.txt:186: # for the Windows resource limits.
It seems like the above changes should be reverted

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode200
CMakeLists.txt:200: # tarball) we use date to get current time for timestamp.
I would add something like "This is not ideal as it confuses the build timestamp
with the commit timestamp."

[zhaoqin, 2016-04-04 21:33:18]

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt
File CMakeLists.txt (right):

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode184
CMakeLists.txt:184: # We want the committer date (not author date) (xref
i#1565).  We request UNIX
On 2016/04/04 21:26:22, bruening wrote:
> Shouldn't the DR stay there?  This is a DrM file.

Done.

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode186
CMakeLists.txt:186: # for the Windows resource limits.
On 2016/04/04 21:26:22, bruening wrote:
> It seems like the above changes should be reverted

Done.

https://codereview.appspot.com/289680043/diff/20001/CMakeLists.txt#newcode200
CMakeLists.txt:200: # tarball) we use date to get current time for timestamp.
On 2016/04/04 21:26:22, bruening wrote:
> I would add something like "This is not ideal as it confuses the build
timestamp
> with the commit timestamp."

Done.

[zhaoqin, 2016-04-04 21:35:19]

Committed as
https://github.com/DynamoRIO/drmemory/commit/fe9124b68f30c99d13e49990edf6cad3...

Final commit log: 
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DR-i#1565: set VERSION_NUMBER_PATCHLEVEL even on git log failure

We try different ways to set VERSION_NUMBER_PATCHLEVEL on git log failure.

Review-URL: https://codereview.appspot.com/289680043
---------------