going back to a previous version of the main repository

I have the following problem: - I have implemented this program as a library for a bigger software. This library depends on other libraries from the software. Now each time I modify something I am committing my changes, and from time to time I am updating 开发者_如何学Cthe main repository.

My library was working good, compiling running and all, I just wanted to make some improvements and at one point I updated the repository so some of the dependent libraries on which my library depends on were modify and now my library does not compile. SO I want to go back to an older version of the main repository and copy again the old files in the dependent libraries, as if the new changes are not taken into considerations anymore. Is this possible? How can I achieve this? Is this dangerous? (I also try to fix the problem, but it is not so easy apparently).

Thanks in advance, madalina

You can back-date (that is, update to an old revision) individual files and sub-folders in your working copy, so you should be able to pick and choose which files you want to roll back in order to get everything into a consistent, working state again.