How to turn off proguard completely?

I have an Android application on which I don't want to do anything regarding optimization/obfuscation/etc. I deleted the (auto-generated) proguard configuration file (proguard.cfg) but I think my library projects' files are still being obfuscated, because in the crash reports I don't see the line numbers - `Unknown Source` is shown instead. How can I turn off proguard completely? Also, how can I validate that it was indeed turned off?