It seems solaris prefers "sys/loadavg.h" over "stdlib.h" when
fetching the load average.
For Illumos based OSes it was required to include "sys/time.h" to
ensure that "hrtime_t" was defined.
https://www.illumos.org/issues/6002
It also required setting the ldflags "-fno-stack-protector -lssp" to
avoid undefined symbols when linking with gcc.
/opt/local/go/pkg/tool/solaris_amd64/link: running gcc failed: exit status 1
Undefined first referenced
symbol in file
__stack_chk_fail /tmp/go-link-138622936/000002.o
__stack_chk_guard /tmp/go-link-138622936/000002.o
