A short guide to building the avr toolchain from source. Better version available at http://www.nongnu.org/avr-libc/user-manual/install_tools.html

Where to get the required shit

	Binutils:	http://ftp.gnu.org/gnu/binutils/
	GCC:		http://www.gnu.org/prep/ftp.html or https://gcc.gnu.org/mirrors.html
	LibC:		http://download.savannah.gnu.org/releases/avr-libc/
	Avrdude:	http://download.savannah.gnu.org/releases/avrdude/

	crtatmega328pb.o io.h iom328pb.h libatmega328pb.a avrdude.conf:		https://github.com/watterott/ATmega328PB-Testing

Install the necessary packages. Avrdude is fine from the repos. Check the output for configure if you want moar support.

	$ sudo apt-get install build-essentials screen flex bison libmpc-dev libelf-dev libusb-dev libusb-1.0-0-dev libftdi-dev 

Commands, do read them before blindly executing

	$ PREFIX=$HOME/local/avr
	$ export PREFIX
	$ PATH=$PATH:$PREFIX/bin
	$ export PATH

	$ bunzip2 -c binutils-<version>.tar.bz2 | tar xf -
	$ cd binutils-<version>
	$ mkdir obj-avr
	$ cd obj-avr
	$ ../configure --prefix=$PREFIX --target=avr --disable-nls
	$ make
	$ make install

	$ bunzip2 -c gcc-<version>.tar.bz2 | tar xf -
	$ cd gcc-<version>
	$ mkdir obj-avr
	$ cd obj-avr
	$ ../configure --prefix=$PREFIX --target=avr --enable-languages=c,c++ --disable-nls --disable-libssp --with-dwarf2
	$ make
	$ make install

	$ bunzip2 -c avr-libc-<version>.tar.bz2 | tar xf -
	$ cd avr-libc-<version>
	$ ./configure --prefix=$PREFIX --build=`./config.guess` --host=avr
	$ make
	$ make install

	$ gunzip -c avrdude-<version>.tar.gz | tar xf -
	$ cd avrdude-<version>
	$ mkdir obj-avr
	$ cd obj-avr
	$ ../configure --prefix=$PREFIX
	$ make
	$ make install

Because fuck the repo managers, we are still missing the files for atmega328pb. Add them to their relevant locations in your $PREFIX (or default location if you didn't provide prefix.

To get avrdude working with atmega328pb, add to $PREFIX/avrdude.conf after the definition of m328p (systemwide is usually at /etc/avrdude.conf if you installed from repos)

	part parent "m328"
	    id			= "m328pb";
	    desc		= "ATmega328PB";
	    signature		= 0x1e 0x95 0x16;

	    ocdrev              = 1;
	;

It should now work.