Git launches mergetool without any arguments

Question

On machine A, git mergetool runs Beyond Compare 3 as expected. On machine B, BC3 starts but isn't passed any arguments on the command line, thus showing the intro screen instead of the actual merge.

I copied the config from machine A to machine B, and git config --list is identical apart from the installation path and push.default=simple:

merge.tool=bc3
mergetool.bc3='C:/Apps/BeyondCompare3/BCompare.exe'
mergetool.bc3.cmd='C:/Apps/BeyondCompare3/BCompare.exe'
mergetool.bc3.path=C:\Apps\BeyondCompare3\bcomp.exe
push.default=simple

The only other differences are that machine A has git 1.7.11 under Win7 64-bit, while machine B (the one that doesn't work) has git 1.8.4 under Win8 32-bit.

ProcessHacker shows that the command line on machine A (for the exact same repository, bit for bit) is:

"c:\Program Files (x86)\Beyond Compare 3\bcomp.exe" 
        ./somefile.cs.LOCAL.4192.cs 
        ./somefile.cs.REMOTE.4192.cs
        ./somefile.cs.BASE.4192.cs
        -mergeoutput=somefile.cs /BCompWnd=$00140644

while on the broken machine B it's simply:

c:\Apps\BeyondCompare3\BCompare.exe

Which magic incantation do I need here?

Git launches mergetool without any arguments

1 Answers