"/mingw64/bin/wish: Bad address" when starting git gui multiple times

[gix]

• I was not able to find an open or closed issue matching what I'm seeing

Setup

• Which version of Git for Windows are you using? Is it 32-bit or 64-bit?

git version 2.47.1.windows.1
cpu: x86_64
built from commit: 2cd22437f64229935dc564db969cbcbfed5e9045
sizeof-long: 4
sizeof-size_t: 8
shell-path: D:/git-sdk-64-build-installers/usr/bin/sh
feature: fsmonitor--daemon
libcurl: 8.11.0
OpenSSL: OpenSSL 3.2.3 3 Sep 2024
zlib: 1.3.1

• Which version of Windows are you running? Vista, 7, 8, 10? Is it 32-bit or 64-bit?

Windows 10 22H2, 64-bit

10.0.19045.5247

• What options did you set as part of the installation? Or did you choose the
  defaults?

Editor Option: VIM
Custom Editor Path:
Default Branch Option:
Path Option: Cmd
SSH Option: ExternalOpenSSH
Tortoise Option: false
CURL Option: WinSSL
CRLF Option: CRLFCommitAsIs
Bash Terminal Option: MinTTY
Git Pull Behavior Option: FFOnly
Use Credential Manager: Enabled
Performance Tweaks FSCache: Enabled
Enable Symlinks: Enabled
Enable FSMonitor: Disabled

Details

When I try to open git gui a second time (while the first one is still running) the following occurs:

> git gui
> git gui
C:/Program Files/Git/mingw64/libexec/git-core\git-gui: line 3: /mingw64/bin/wish: Bad address
C:/Program Files/Git/mingw64/libexec/git-core\git-gui: line 3: /mingw64/bin/wish: No error
>

• It fails in PowerShell 7, 5 or cmd.exe.
• It works fine when starting the second instance from a separate terminal process.
• It works fine using git v2.46.2.
• It also fails using git v2.48.0-rc0.
• It also fails in a non-dev test VM which should have a mostly pristine environment.
• Closing the first instance allows opening a new instance again (but not a second one).

[dscho]

Strange. It works when I prefix exec wish "$0" -- "$@" in C:\Program Files\Git\mingw64\libexec\git-core\git-gui with exec >/dev/null;. This would suggest that the culprit is the MSYS2 runtime that somehow closes stdout when it is still needed.

Another work-around is to run git-gui instead of git gui (although the former is deprecated and the latter should work).

[ganlvtech]

+1

ok with git version 2.45.1.windows.1
bad with git version 2.47.1.windows.2

• Run git gui in PowerShell twice got wish: Bad address (executable: C:\Program Files\Git\cmd\git.exe)
• Run git gui & in Git Bash twice got wish: Bad address (executable: /mingw64/bin/git)
• Run git-gui & twice is ok (executable: `/cmd/git-gui)
• Run /mingw64/libexec/git-core/git-gui & twice is also ok

[dscho]

@ganlvtech I kind of already established that the problem is the MSYS2 runtime, if you want to contribute to understanding the problem in more detail, you may want to bisect the snapshots to pinpoint the first version with the regression.