These are my defined symbols in C and C++ compiler
SAM3X8E
USB_PID=0x003E
USBCON
These are my included paths
"${workspace_loc:/${ProjName}/src/core}"
"${workspace_loc:/${ProjName}/src/lib/CMSIS/Device/ATMEL}"
"${workspace_loc:/${ProjName}/src/lib/CMSIS/CMSIS/Include}"
"${workspace_loc:/${ProjName}/src/lib/libsam/include}"
"${workspace_loc:/${ProjName}/src/lib/libsam}"
"${workspace_loc:/${ProjName}/src/lib/CMSIS/Device/ATMEL/sam3xa/include}"
"${workspace_loc:/${ProjName}/src/lib/variants/arduino_due_x}"