Cannot cross-compile APM on ubuntu 14.04 64 bit

I just started to build APM from source code. I Just followed the following steps:

sudo git clone --depth 1 GitHub - raspberrypi/tools /opt/tools

export PATH=/opt/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin:$PATH

git clone GitHub - ArduPilot/ardupilot: ArduPlane, ArduCopter, ArduRover, ArduSub source
cd ardupilot
git submodule update --init

alias waf=“$PWD/modules/waf/waf-light”

waf configure --board=navio2

However, I got this error: