../../common/io/timerfd.c: In function 'timerfd_open':
../../common/io/timerfd.c:125:10: error: return makes integer from pointer without a cast [-Werror=int-conversion]
   return (NULL);
          ^
../../common/io/timerfd.c: In function 'timerfd_ioctl':
../../common/io/timerfd.c:334:29: error: comparison between pointer and integer [-Werror]
   if (st.tfd_settime_ovalue != NULL) {
                             ^~
../../common/io/timerfd.c:376:41: error: comparison between pointer and integer [-Werror]
   if (err != 0 || st.tfd_settime_ovalue == NULL)
                                         ^~
In file included from ../../common/sys/param.h:48:0,
                 from ../../common/sys/t_lock.h:38,
                 from ../../common/sys/map.h:35,
                 from ../../common/sys/ddi.h:37,
                 from ../../common/io/timerfd.c:22:
../../common/io/timerfd.c: In function 'timerfd_attach':
../../common/sys/null.h:32:14: error: passing argument 6 of 'ddi_create_minor_node' makes integer from pointer without a cast [-Werror=int-conversion]
 #define NULL ((void *)0)
              ^
../../common/io/timerfd.c:458:39: note: in expansion of macro 'NULL'
      TIMERFDMNRN_TIMERFD, DDI_PSEUDO, NULL) == DDI_FAILURE) {
                                       ^~~~
In file included from ../../common/io/timerfd.c:23:0:
../../common/sys/sunddi.h:1564:1: note: expected 'int' but argument is of type 'void *'
 ddi_create_minor_node(dev_info_t *dip, char *name, int spec_type,
 ^~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors