git-diff-index does not refresh the index for you, so using it for a "-dirty" check can give misleading results. Commit 6147b1cf19651 ("scripts/setlocalversion: git: Make -dirty check more robust") tried to fix this by switching to git-status, but it overlooked the fact that git-status also writes to the .git directory of the source tree, which is definitely not kosher for an out-of-tree (O=) build. That is getting reverted.
Fortunately, git-status now supports avoiding writing to the index via the --no-optional-locks flag, as of git 2.14. It still calculates an up-to-date index, but it avoids writing it out to the .git directory. So, let's retry the solution from commit 6147b1cf19651 using this new flag first, and if it fails, we assume this is an older version of git and just use the old git-diff-index method. It's hairy to get the 'grep -vq' (inverted matching) correct by stashing the output of git-status (you have to be careful about the difference betwen "empty stdin" and "blank line on stdin"), so just pipe the output directly to grep and use a regex that's good enough for both the git-status and git-diff-index version. Cc: Genki Sky <s...@genki.is> Cc: Christian Kujau <li...@nerdbynature.de> Cc: Guenter Roeck <li...@roeck-us.net> Suggested-by: Alexander Kapshuk <alexander.kaps...@gmail.com> Signed-off-by: Brian Norris <briannor...@chromium.org> --- On Tue, Nov 13, 2018 at 10:32:16AM -0800, Brian Norris wrote: > I can submit it. I expect Masahiro-san would prefer a proper v2 patch > for review, given how much would change from my v1. Done v1 -> v2: * handle empty (non-dirty) results properly, where echo "${empty_variable}" | grep -qv "${something_else}" always has a 0 exit status (a blank line is an inverted match for any non-blank expression). Just pipe directly to grep instead, with a hopefully-not-too-permissive regex to handle both versions. * actually tested with dirty and non-dirty trees this time scripts/setlocalversion | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/scripts/setlocalversion b/scripts/setlocalversion index 71f39410691b..2190de4b57ad 100755 --- a/scripts/setlocalversion +++ b/scripts/setlocalversion @@ -73,8 +73,16 @@ scm_version() printf -- '-svn%s' "`git svn find-rev $head`" fi - # Check for uncommitted changes - if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then + # Check for uncommitted changes. + # First, with git-status, but --no-optional-locks is only + # supported in git >= 2.14, so fall back to git-diff-index if + # it fails. Note that git-diff-index does not refresh the + # index, so it may give misleading results. See + # git-update-index(1), git-diff-index(1), and git-status(1). + if { + git --no-optional-locks status -uno --porcelain 2>/dev/null || + git diff-index --name-only HEAD + } | grep -qv '^\(.. \)\?scripts/package'; then printf '%s' -dirty fi -- 2.19.1.930.g4563a0d9d0-goog