RTEMS 6 removed the BSP spec file, so the flag fails the RTEMS 6 toolchain at CMake's compiler identification. Select it on CMAKE_SYSTEM_VERSION; an unset or pre-6 version keeps it.
RTEMS 6 removed the BSP spec file, so the flag fails the RTEMS 6 toolchain at CMake's compiler identification. Select it on CMAKE_SYSTEM_VERSION; an unset or pre-6 version keeps it.