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diff --git a/third_party/git/Documentation/howto/revert-branch-rebase.txt b/third_party/git/Documentation/howto/revert-branch-rebase.txt deleted file mode 100644 index a3e5595a569a..000000000000 --- a/third_party/git/Documentation/howto/revert-branch-rebase.txt +++ /dev/null @@ -1,187 +0,0 @@ -From: Junio C Hamano <gitster@pobox.com> -To: git@vger.kernel.org -Subject: [HOWTO] Reverting an existing commit -Abstract: In this article, JC gives a small real-life example of using - 'git revert' command, and using a temporary branch and tag for safety - and easier sanity checking. -Date: Mon, 29 Aug 2005 21:39:02 -0700 -Content-type: text/asciidoc -Message-ID: <7voe7g3uop.fsf@assigned-by-dhcp.cox.net> - -How to revert an existing commit -================================ - -One of the changes I pulled into the 'master' branch turns out to -break building Git with GCC 2.95. While they were well-intentioned -portability fixes, keeping things working with gcc-2.95 was also -important. Here is what I did to revert the change in the 'master' -branch and to adjust the 'seen' branch, using core Git tools and -barebone Porcelain. - -First, prepare a throw-away branch in case I screw things up. - ------------------------------------------------- -$ git checkout -b revert-c99 master ------------------------------------------------- - -Now I am on the 'revert-c99' branch. Let's figure out which commit to -revert. I happen to know that the top of the 'master' branch is a -merge, and its second parent (i.e. foreign commit I merged from) has -the change I would want to undo. Further I happen to know that that -merge introduced 5 commits or so: - ------------------------------------------------- -$ git show-branch --more=4 master master^2 | head -* [master] Merge refs/heads/portable from http://www.cs.berkeley.... - ! [master^2] Replace C99 array initializers with code. --- -- [master] Merge refs/heads/portable from http://www.cs.berkeley.... -*+ [master^2] Replace C99 array initializers with code. -*+ [master^2~1] Replace unsetenv() and setenv() with older putenv(). -*+ [master^2~2] Include sys/time.h in daemon.c. -*+ [master^2~3] Fix ?: statements. -*+ [master^2~4] Replace zero-length array decls with []. -* [master~1] tutorial note about git branch ------------------------------------------------- - -The '--more=4' above means "after we reach the merge base of refs, -show until we display four more common commits". That last commit -would have been where the "portable" branch was forked from the main -git.git repository, so this would show everything on both branches -since then. I just limited the output to the first handful using -'head'. - -Now I know 'master^2~4' (pronounce it as "find the second parent of -the 'master', and then go four generations back following the first -parent") is the one I would want to revert. Since I also want to say -why I am reverting it, the '-n' flag is given to 'git revert'. This -prevents it from actually making a commit, and instead 'git revert' -leaves the commit log message it wanted to use in '.msg' file: - ------------------------------------------------- -$ git revert -n master^2~4 -$ cat .msg -Revert "Replace zero-length array decls with []." - -This reverts 6c5f9baa3bc0d63e141e0afc23110205379905a4 commit. -$ git diff HEAD ;# to make sure what we are reverting makes sense. -$ make CC=gcc-2.95 clean test ;# make sure it fixed the breakage. -$ make clean test ;# make sure it did not cause other breakage. ------------------------------------------------- - -The reverted change makes sense (from reading the 'diff' output), does -fix the problem (from 'make CC=gcc-2.95' test), and does not cause new -breakage (from the last 'make test'). I'm ready to commit: - ------------------------------------------------- -$ git commit -a -s ;# read .msg into the log, - # and explain why I am reverting. ------------------------------------------------- - -I could have screwed up in any of the above steps, but in the worst -case I could just have done 'git checkout master' to start over. -Fortunately I did not have to; what I have in the current branch -'revert-c99' is what I want. So merge that back into 'master': - ------------------------------------------------- -$ git checkout master -$ git merge revert-c99 ;# this should be a fast-forward -Updating from 10d781b9caa4f71495c7b34963bef137216f86a8 to e3a693c... - cache.h | 8 ++++---- - commit.c | 2 +- - ls-files.c | 2 +- - receive-pack.c | 2 +- - server-info.c | 2 +- - 5 files changed, 8 insertions(+), 8 deletions(-) ------------------------------------------------- - -There is no need to redo the test at this point. We fast-forwarded -and we know 'master' matches 'revert-c99' exactly. In fact: - ------------------------------------------------- -$ git diff master..revert-c99 ------------------------------------------------- - -says nothing. - -Then we rebase the 'seen' branch as usual. - ------------------------------------------------- -$ git checkout seen -$ git tag seen-anchor seen -$ git rebase master -* Applying: Redo "revert" using three-way merge machinery. -First trying simple merge strategy to cherry-pick. -* Applying: Remove git-apply-patch-script. -First trying simple merge strategy to cherry-pick. -Simple cherry-pick fails; trying Automatic cherry-pick. -Removing Documentation/git-apply-patch-script.txt -Removing git-apply-patch-script -* Applying: Document "git cherry-pick" and "git revert" -First trying simple merge strategy to cherry-pick. -* Applying: mailinfo and applymbox updates -First trying simple merge strategy to cherry-pick. -* Applying: Show commits in topo order and name all commits. -First trying simple merge strategy to cherry-pick. -* Applying: More documentation updates. -First trying simple merge strategy to cherry-pick. ------------------------------------------------- - -The temporary tag 'seen-anchor' is me just being careful, in case 'git -rebase' screws up. After this, I can do these for sanity check: - ------------------------------------------------- -$ git diff seen-anchor..seen ;# make sure we got the master fix. -$ make CC=gcc-2.95 clean test ;# make sure it fixed the breakage. -$ make clean test ;# make sure it did not cause other breakage. ------------------------------------------------- - -Everything is in the good order. I do not need the temporary branch -or tag anymore, so remove them: - ------------------------------------------------- -$ rm -f .git/refs/tags/seen-anchor -$ git branch -d revert-c99 ------------------------------------------------- - -It was an emergency fix, so we might as well merge it into the -'release candidate' branch, although I expect the next release would -be some days off: - ------------------------------------------------- -$ git checkout rc -$ git pull . master -Packing 0 objects -Unpacking 0 objects - -* commit-ish: e3a693c... refs/heads/master from . -Trying to merge e3a693c... into 8c1f5f0... using 10d781b... -Committed merge 7fb9b7262a1d1e0a47bbfdcbbcf50ce0635d3f8f - cache.h | 8 ++++---- - commit.c | 2 +- - ls-files.c | 2 +- - receive-pack.c | 2 +- - server-info.c | 2 +- - 5 files changed, 8 insertions(+), 8 deletions(-) ------------------------------------------------- - -And the final repository status looks like this: - ------------------------------------------------- -$ git show-branch --more=1 master seen rc -! [master] Revert "Replace zero-length array decls with []." - ! [seen] git-repack: Add option to repack all objects. - * [rc] Merge refs/heads/master from . ---- - + [seen] git-repack: Add option to repack all objects. - + [seen~1] More documentation updates. - + [seen~2] Show commits in topo order and name all commits. - + [seen~3] mailinfo and applymbox updates - + [seen~4] Document "git cherry-pick" and "git revert" - + [seen~5] Remove git-apply-patch-script. - + [seen~6] Redo "revert" using three-way merge machinery. - - [rc] Merge refs/heads/master from . -++* [master] Revert "Replace zero-length array decls with []." - - [rc~1] Merge refs/heads/master from . -... [master~1] Merge refs/heads/portable from http://www.cs.berkeley.... ------------------------------------------------- |