1system_stubs_ss = ss.source_set() 2system_stubs_ss.add(when: 'CONFIG_XEN', if_false: files('xen-stub.c')) 3system_stubs_ss.add(when: 'CONFIG_KVM', if_false: files('kvm-stub.c')) 4system_stubs_ss.add(when: 'CONFIG_TCG', if_false: files('tcg-stub.c')) 5system_stubs_ss.add(when: 'CONFIG_HVF', if_false: files('hvf-stub.c')) 6 7specific_ss.add_all(when: ['CONFIG_SYSTEM_ONLY'], if_true: system_stubs_ss) 8