Gernot Bauer

Proper example to reproduce the issue: ```rust #![feature(autodiff)] #[autodiff(df2f, Forward, Const, Dual, Dual)] #[no_mangle] pub fn _f2(x: &[f64], y: f64) -> f64 { let xy: Vec = x.iter().map(|xi| xi /...

Is there anything I have to consider when re-building the compiler? I pulled the latest changes and recompiled but I end up with the same error.

We don't have special treatment (see [here](https://github.com/itt-ustutt/num-dual/blob/f4123e30702ec3786c44d70ff66c9afc00583338/src/derivatives.rs#L63-L71)). Taking the derivative of `sqrt(0.0)` will return `NaN`. But I don't think that's the issue here. Changing to a different operation (`pow`, `ln`,...

@ZuseZ4 Thanks! Just wanted to let you know that I re-ran the benchmarks I shared with you in August and the application of num-dual and enzyme are now equally fast...

Thanks for the ping. If time permits, I'll run some more tests.