+
+## `avr-gcc: internal compiler error: Abort trap: 6 (program cc1)` on MacOS
+This is an issue with updating on brew, causing symlinks that avr-gcc depend on getting mangled.
+
+The solution is to remove and reinstall all affected modules.
+
+```
+brew rm avr-gcc
+brew rm dfu-programmer
+brew rm dfu-util
+brew rm gcc-arm-none-eabi
+brew rm avrdude
+brew install avr-gcc
+brew install dfu-programmer
+brew install dfu-util
+brew install gcc-arm-none-eabi
+brew install avrdude
+```
+
+### avr-gcc 8.1 and LUFA
+
+If you updated your avr-gcc to above 7 you may see errors involving LUFA. For example:
+
+`lib/lufa/LUFA/Drivers/USB/Class/Device/AudioClassDevice.h:380:5: error: 'const' attribute on function returning 'void'`
+
+For now, you need to rollback avr-gcc to 7 in brew.
+
+```
+brew uninstall --force avr-gcc
+brew install avr-gcc@8
+brew link --force avr-gcc@8
+```
+
+### I just flashed my keyboard and it does nothing/keypresses don't register - it's also ARM (rev6 planck, clueboard 60, hs60v2, etc...) (Feb 2019)
+Due to how EEPROM works on ARM based chips, saved settings may no longer be valid. This affects the default layers, and *may*, under certain circumstances we are still figuring out, make the keyboard unusable. Resetting the EEPROM will correct this.
+
+[Planck rev6 reset EEPROM](https://cdn.discordapp.com/attachments/473506116718952450/539284620861243409/planck_rev6_default.bin) can be used to force an eeprom reset. After flashing this image, flash your normal firmware again which should restore your keyboard to _normal_ working order.
+[Preonic rev3 reset EEPROM](https://cdn.discordapp.com/attachments/473506116718952450/537849497313738762/preonic_rev3_default.bin)
+
+If bootmagic is enabled in any form, you should be able to do this too (see [Bootmagic docs](feature_bootmagic.md) and keyboard info for specifics on how to do this).