Hi Phillip, On Wed, Feb 19, 2020 at 3:01 AM Phillip Wood <phillip.wood123@xxxxxxxxx> wrote: > > Hi Elijah > > On 18/02/2020 15:59, Elijah Newren wrote: > > On Tue, Feb 18, 2020 at 7:05 AM Phillip Wood <phillip.wood123@xxxxxxxxx> wrote: > >> > >> Hi Elijah > >> > >> On 17/02/2020 19:12, Elijah Newren wrote: > >>> I forgot to add some cc's in GitGitGadget before submitting; adding now... > >>> > >>> On Mon, Feb 17, 2020 at 9:15 AM Elijah Newren via GitGitGadget > >>> <gitgitgadget@xxxxxxxxx> wrote: > >>>> > >>>> From: Elijah Newren <newren@xxxxxxxxx> > >>>> > >>>> A user discovered a case where they had a stack of 20 simple commits to > >>>> rebase, and the rebase would succeed in picking the first commit and > >>>> then error out with a pair of "Could not execute the todo command" and > >>>> "Your local changes to the following files would be overwritten by > >>>> merge" messages. > >>>> > >>>> Their steps actually made use of the -i flag, but I switched it over to > >>>> -m to make it simpler to trigger the bug. With that flag, it bisects > >>>> back to commit 68aa495b590d (rebase: implement --merge via the > >>>> interactive machinery, 2018-12-11), but that's misleading. If you > >>>> change the -m flag to --keep-empty, then the problem persists and will > >>>> bisect back to 356ee4659bb5 (sequencer: try to commit without forking > >>>> 'git commit', 2017-11-24) > >>>> > >>>> After playing with the testcase for a bit, I discovered that added > >>>> --exec "sleep 1" to the command line makes the rebase succeed, making me > >>>> suspect there is some kind of discard and reloading of caches that lead > >>>> us to believe that something is stat dirty, but I didn't succeed in > >>>> digging any further than that. > > I think `--exec true` would be better as it makes it clear that it's not > a timing issue. I've changed do_recursive_merge() to print the mtime and > mode of "DS" before and after the merge which gives > > HEAD is now at abd8fe3 side1 > Rebasing (1/2) # picking commit1 > DS mtime, mode before merge 1582109854, 120000 > DS mtime, mode after merge 0, 120000 > Rebasing (2/2) # picking commit2 > DS mtime, mode before merge 0, 120000 > error: Your local changes to the following files would be overwritten by > merge: > DS > > So it looks like the problem is that when we pick commit1 we don't > update the index entry for DS properly in merge_trees() > > Best Wishes > > Phillip Oh, indeed, so this was my bug. Thanks for jumping in and investigating; I probably should have found that lead but I just didn't. Anyway, with your extra information I dug around for a bit and I think I found the fix. I'll post it soon.
