Fatal error: atomic file not found

I’m trying to build ArduCopter on a Snapdragon Flight, but I’m getting this error:

In file included from /home/ja/Snapdragon/ardupilot/libraries/AP_HAL/utility/RingBuffer.cpp:4:
/home/ja/Snapdragon/ardupilot/libraries/AP_HAL/utility/RingBuffer.h:3:10: fatal error: ‘atomic’ file
not found
#include < atomic >
^
In file included from /home/ja/Snapdragon/ardupilot/libraries/AP_HAL_Linux/qflight/dsp_functions.cpp:47:
/home/ja/Snapdragon/ardupilot/libraries/AP_HAL/utility/RingBuffer.h:3:10: fatal error: ‘atomic’ file
not found
#include < atomic >

Has anyone encountered this issue before?