GNU compiler warnings

[ritwit]

This is a minor issue but worth addressing.

The GCC compiler throws many warnings when compiling the C++ extensions of Dscribe. Some of them are obvious and easy to fix. It may be a good idea to take a look at each of these warnings and ensure that they are benign.

I can submit a PR to fix some of the easy ones.

Thanks!

[lauri-codes]

Hi @ritwit!

You're absolutely right. We have mostly ignored these warnings which is definitely not a good practice... Thank you also for your pull request: I will take a look and include it in the next release.