command 'gc' has no effect in parallel mode

[kyeongsoo]

First of all, great thanks for your providing this nice tool.
Thanks to mu-repo, now I can better manage multiple git repositories in a more systematic way.

The git command 'gc', however, seems to have no effects when running it by "mu gc" as shown below:

> mu gc

  Bin : git gc

  Learning : git gc

  Research : git gc

  dotFiles : git gc

  elisp : git gc 

Running 'gc' through git aliases throught the stackoverflow solution suggested by Jose Luis Blanco, however, result in the following:

> git all gc
Bin/.git
Counting objects: 65, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (47/47), done.
Writing objects: 100% (65/65), done.
Total 65 (delta 5), reused 65 (delta 5)

Learning/.git
Counting objects: 6, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (6/6), done.
Writing objects: 100% (6/6), done.
Total 6 (delta 0), reused 6 (delta 0)
...

Note that other git commands show the resulting messages unlike the 'gc'.

[fabioz]

Just wanted to say that it does work in serial mode:

i.e.:

mu set-var serial=1
mu gc

But not in parallel mode.

I don't really know why git gc fails in parallel mode (maybe git gc needs a real tty which is not available when working in parallel mode?).