POSITION_INDEPENDENT_CODE ON for static compilations

[sanguinariojoe]

You really want to add that option here. Otherwise static linking inside dynamic libraries would be impossible (like it is usually the case when making Python wheels)

[ebiggers]

You can already set -DCMAKE_POSITION_INDEPENDENT_CODE=1 when running cmake, if you want to. Is there a strong reason you want libdeflate to force it on for the static library, overriding the cmake default behavior?

[sanguinariojoe]

Hey! Sorry, I missed this reply. Luckily @cary-ilm drawn my attention on this.

That option seems to work just fine.

https://github.com/sanguinariojoe/openexr/actions/runs/5701914625

I actually did not know you can add such an option to CMake... My bad