On Thu, Jan 23, 2020 at 06:04:12PM +0100, SZEDER Gábor wrote: > On Thu, Jan 23, 2020 at 11:36:49AM -0500, Eric Sunshine wrote: > > > Are you sure it's a recent regression? I have no experience with > > > 'gitk' in Git for Windows, but on Linux this has been broken for quite > > > some time, namely since 784b7e2f25 (gitk: Fix "External diff" with > > > separate work tree, 2011-04-04) in the v1.7 era. FWIW, reverting that > > > commit on top of v2.25.0 makes 'gitk' work again in bare repositories. > > > > It's a new regression introduced by 2d92ab32fd (rev-parse: make > > --show-toplevel without a worktree an error, 2019-11-19), as far as I > > can tell. > > Oh, that's interesting. > > My local commit reverting 784b7e2f25 that I build my Git with is newer > than 2d92ab32fd, so maybe that's why I haven't recalled seeing this > issue earlier. I did try to bisect it, but had a real hard time with > gitk being subtree merged, and ultimately gave up on that, and started > to look for a commit adding '--show-toplevel' to 'gitk', which lead me > to 784b7e2f25, I reverted it, my issue went away, which then lead me > to the wrong conclusion. Oh, this is interesting indeed :) I have a couple of older Git versions lying around, so I can quickly ballpark a revision range for a regression, without checking out and building older versions. This has always worked well so far, because Git looks for its non-builtin commands in the hardcoded exec-path that was specified at build time, while builtin commands are, well, builtins. Alas, 'gitk' is not a regular Git command, and it runs whatever 'git' executable comes first in PATH, which in my case was a recent build already containing 2d92ab32fd. $ ~/src/git/BUILDS/v1.8.0/bin/git --exec-path /home/szeder/src/git/BUILDS/v1.8.0/libexec/git-core $ cd .git $ ~/src/git/BUILDS/v1.8.0/bin/gitk Error in startup script: fatal: this operation must be run in a work tree while executing "exec git rev-parse --show-toplevel" invoked from within "set worktree [exec git rev-parse --show-toplevel]" (file "/home/szeder/src/git/BUILDS/v1.8.0/bin/gitk" line 11810) $ PATH=~/src/git/BUILDS/v1.8.0/bin:"$PATH" ~/src/git/BUILDS/v1.8.0/bin/gitk # Works even in the .git directory! $ PATH=~/src/git/BUILDS/v2.24.0/bin:"$PATH" ~/src/git/BUILDS/v2.24.0/bin/gitk # This works, too! With this newly gained knowledge I added 'bin-wrappers' to $PATH when running gitk built from 2d92ab32fd and its parent, and indeed that's the commit that introduced this regression.