"/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).