diff --git a/libc/libc.arm.map b/libc/libc.arm.map
index 06856c8..0749fc8 100644
--- a/libc/libc.arm.map
+++ b/libc/libc.arm.map
@@ -1320,9 +1320,10 @@
 
 LIBC_P {
   global:
-    __freading; # future
-    __fwriting; # future
-    getlogin_r; # future
+    __freading; # introduced=P
+    __fwriting; # introduced=P
+    getlogin_r; # introduced=P
+    syncfs; # introduced=P
 } LIBC_O;
 
 LIBC_PRIVATE {