diff --git a/libc/include/sys/sysinfo.h b/libc/include/sys/sysinfo.h
index b66bc8e..9a10d64 100644
--- a/libc/include/sys/sysinfo.h
+++ b/libc/include/sys/sysinfo.h
@@ -35,13 +35,13 @@
 
 int sysinfo(struct sysinfo* info);
 
-int get_nprocs_conf(void);
+int get_nprocs_conf(void) __INTRODUCED_IN(23);
 
-int get_nprocs(void);
+int get_nprocs(void) __INTRODUCED_IN(23);
 
-long get_phys_pages(void);
+long get_phys_pages(void) __INTRODUCED_IN(23);
 
-long get_avphys_pages(void);
+long get_avphys_pages(void) __INTRODUCED_IN(23);
 
 __END_DECLS