Compile Linux Kernel ,RTAI and LinuxCNC from Source Code

I used the default path to compile and install RTAI, isn't it /usr/realtime? How to find the actual path to the rtai modules？As the same time ,thank all of you very much for the contribution, I feel linuxcnc is very very great!

just have a look around /usr/realtime

This is the linuxcnc configuration information and compilation information

This is the linuxcnc configuration information and compilation information? Is my rtai still incorrect? Why is there such a thing as pcl720?

Arthur_L wrote: This is the linuxcnc configuration information and compilation information? Is my rtai still incorrect? Why is there such a thing as pcl720?

github.com/LinuxCNC/linuxcnc/blob/master.../drivers/pcl720.comp

It's a card supported by Linuxcnc.
From
"your_linuxcnc_base_dir"/src/hal/drivers/pcl720.comp

component pcl720 """Driver for the Advantech PCL 720 card.""";
description """This driver supports the Advantech PCL720 ISA card. It might
work with the PCI version too, but this is untested.
It creates hal pins corresonding to the digital inputs and outputs, but does
not support the the counters/timers.""";

It wouldn't be a gcc 5.4 issue ?