Package request: AVRGCC toolchain for atmel MCUs and the Arduino IDE
It’s a big task, described here http://nongnu.org/avr-libc/user-manual/install_tools.html and here http://avr-eclipse.sourceforge.net/wiki/index.php/The_AVR_GCC_Toolchain
Sources are here: http://distribute.atmel.no/tools/opensource/Atmel-AVR-GNU-Toolchain/, which Arduino patch here https://github.com/arduino/toolchain-avr
The IDE is here: https://github.com/arduino/Arduino
(from redmine: issue id 5194, created on 2016-02-28)