gcc-config: could not run/locate 'avr-gcc-ar'

I'm trying to build an arduino sketch, but it fails with error: > "/usr/bin/avr-gcc-ar" rcs "/tmp/arduino_build_191139/core/core.a" "/tmp/arduino_build_191139/core/wiring_pulse.S.o"
gcc-config: error: could not run/locate 'avr-gcc-ar'
exit status 1
Error compiling for board Arduino Nano. I'm using Gentoo with crossdev for avr and Arduino studio to compile. avr-g++ version is avr-gcc (Gentoo 6.4.0-r1 p1.3) 6.4.0. gcc-config: > avr-6.4.0 *
x86_64-pc-linux-gnu-6.4.0 * Does anybody know how to deal with this error?