sched.h can exist without sched affinity support
diff --git a/configure b/configure
index ca13d70..c4b28d6 100755
--- a/configure
+++ b/configure
@@ -9339,6 +9339,7 @@
select sem_open sem_timedwait sem_getvalue sem_unlink sendfile setegid seteuid \
setgid sethostname \
setlocale setregid setreuid setresuid setresgid setsid setpgid setpgrp setpriority setuid setvbuf \
+ sched_setaffinity \
sigaction sigaltstack siginterrupt sigpending sigrelse \
sigtimedwait sigwait sigwaitinfo snprintf strftime strlcpy symlinkat sync \
sysconf tcgetpgrp tcsetpgrp tempnam timegm times tmpfile tmpnam tmpnam_r \