[PATCH v3 0/3] fixes for split index mode

[Thomas Gummerer <t.gummerer@gmail.com>]

Thanks Brandon and Lars for comments on the previous round.

Previous rounds were at <20171210212202.28231-1-t.gummerer@gmail.com>
and <20171217225122.28941-1-t.gummerer@gmail.com>.

Changes since the previous round:

- reworked the patches to no longer try to use struct repository for
  worktrees, but pass gitdir into read_index_from instead (Thanks
  Brandon :)).  So the fixes that were in 1/3 and 2/3 previously are
  now in 1/3
- 2/3 now fixes t7009 properly.  I thought it was fixed before, but it
  probably just passed the tests because of the GIT_TEST_SPLIT_INDEX
  "randomness".
- The travis job is now only running the 64-bit linux build with split
  index mode to save even more cycles.
- As this wasn't picked up anywhere yet, I took the freedom to rebase
  this onto the current master, which includes sg/travis-fixes, which
  made it a bit easier for me to test.  If this makes the life harder
  for anyone reviewing this let me know and I can base it on the same
  commit previous iterations were based on.

Thomas Gummerer (3):
  read-cache: fix reading the shared index for other repos
  split-index: don't write cache tree with null sha1 entries
  travis: run tests with GIT_TEST_SPLIT_INDEX

 cache-tree.c            |  2 +-
 cache.h                 |  8 +++++---
 ci/run-linux32-build.sh |  1 +
 ci/run-tests.sh         |  4 ++++
 read-cache.c            | 25 ++++++++++++++-----------
 repository.c            |  2 +-
 revision.c              |  3 ++-
 split-index.c           |  2 ++
 t/t1700-split-index.sh  | 19 +++++++++++++++++++
 9 files changed, 49 insertions(+), 17 deletions(-)

-- 
2.16.0.rc1.238.g530d649a79