# Unicorn Hat / Arch Linux / GCC 5

**URL:** <https://forums.pimoroni.com/t/unicorn-hat-arch-linux-gcc-5/745>\
**Category:** Support\
**Created:** [July 9, 2015, 10:01am UTC](https://forums.pimoroni.com/t/unicorn-hat-arch-linux-gcc-5/745 "2015-07-09T10:01:19Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![MrQuacki](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@MrQuacki](https://forums.pimoroni.com/u/MrQuacki)\
**Post date:** [July 9, 2015, 10:01am UTC](https://forums.pimoroni.com/t/unicorn-hat-arch-linux-gcc-5/745/1 "2015-07-09T10:01:19Z")

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As I already posted in [another post](http://forums.pimoroni.com/t/unicorn-hat-rpi2-arch-linux-problems/741) I had some troubles using the unicorn hat library with arch linux. Thought I solved it already, but that was not the case…

The python demo scripts worked well for the first start after each reboot, but the demos still weren’t killable by Ctrl+C and after killing the process, they won’t start again, just generating some cpu load, but not more. after some further investigation I hunted the problem down to the gcc… with gcc-4.9.2 -\> no problems, everything working fine… with gcc-5.1.0 -\> problems as described above :(

I solved it for me by downgrading to gcc 4.9.2 and installing the libraries, so it’s no actual problem for me, just wanted to tell the developers :)

Seems like there are some problems with freeing the interface to the unicorn and gcc 5