build: FAILED conformance/interfaces/timer_create/9-1: build: FAILED: Compiler output: conformance/interfaces/timer_create/9-1.c:39:18: error: variable has incomplete type 'struct sigevent' struct sigevent ev; ^ conformance/interfaces/timer_create/9-1.c:39:9: note: forward declaration of 'struct sigevent' struct sigevent ev; ^ conformance/interfaces/timer_create/9-1.c:44:20: error: use of undeclared identifier 'SIGEV_SIGNAL' ev.sigev_notify = SIGEV_SIGNAL; ^ conformance/interfaces/timer_create/9-1.c:64:6: warning: implicit declaration of function 'timer_create' is invalid in C99 [-Wimplicit-function-declaration] if (timer_create(CLOCK_REALTIME, &ev, &tid) != 0) { ^ conformance/interfaces/timer_create/9-1.c:69:6: warning: implicit declaration of function 'timer_settime' is invalid in C99 [-Wimplicit-function-declaration] if (timer_settime(tid, 0, &its, NULL) != 0) { ^ 2 warnings and 2 errors generated.