Building problem

When I build ArduCopter the following error is returned:

/ardupilot/libraries/AP_RSSI/AP_RSSI.cpp:18:20: fatal error: utility: No such file or directory

This seems a syntax error, since utility is not a library isn’t it?

I’ve cloned the source code using

git clone

Then I open ardupilot and ArduCopter folders.

Finally I use the following instruction

make px4-v2

Everything is Ok, but when AP_RSSI.cpp is built the error is returned

Do you know if theres some error in this version of Ardupilot?

Best regards
Jose Luis