你需要运行

  git submodule update --init --recursive 
 

更新：

子模块add命令实际上克隆了整个回购并将sha1添加到索引。

这可能是新的行为，与以前版本的git相比，克隆没有立即完成。

如果您在索引中没有指向某个特定提交的条目，则git子模块更新将拒绝执行任何操作。这似乎是新的行为。

希望这有助于。

I added a submodule:

git submodule add git://github.com/chneukirchen/rack.git rack

A file .gitmodules was created like:

[submodule "rack"]
path = rack
url = git://github.com/chneukirchen/rack.git

And of course Git knows about it:

git submodule status
30fb044db6ba5ea874ebc44a43bbd80a42676405 rack (1.3.0-64-g30fb044)

I added a submodule by hand, for example, adding to that file:

[submodule "redcloth"]
path = plugins/redcloth
url = git://github.com/jgarber/redcloth.git

And I repeated the previous command:

git submodule init
Submodule 'rack' () registered for path 'rack'

git submodule update
(no output)

git submodule status
30fb044db6ba5ea874ebc44a43bbd80a42676405 rack (1.3.0-64-g30fb044)

So, as far I can see, what I added by hand is ignored. Is there some way to make Git aware of the lines added by hand in the .gitmodules file?

Note: I've also tried to add the lines by hand to the .git/config file and that didn't work either.

You need to run

git submodule update --init --recursive 

UPDATE:

the submodule add command actually clones the entire repo and adds the sha1 to the index.

This may be new behaviour as compared to previous versions of git, the clone was not done immediately.

If you don't have an entry in the index pointing the module to a particular commit, git submodule update refuses to do anything. This seems to be new behaviour.

Hope this helps.