DLib and Compiling Without AVX Support

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# DLib {#dlib}

[DLib](http://dlib.net/) is a modern, C++\-based toolkit which provides several machine learning algorithms.

## Compiling without AVX support {#compiling-without-avx-support}

Especially older CPUs don't support [AVX](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions) (Advanced Vector Extensions) instructions that are used by DLib to optimize their algorithms.

On the affected hardware errors like `Illegal instruction` will occur. In those cases AVX support needs to be disabled:

```nix
self: super: { dlib = super.dlib.override { avxSupport = false; }; }
```

Title: DLib and Compiling Without AVX Support

Summary

DLib is a C++ toolkit that provides machine learning algorithms. Some older CPUs may not support AVX instructions, which are used by DLib for optimization. If errors like 'Illegal instruction' occur, AVX support needs to be disabled by overriding the dlib package.