diff --git a/libc/libc.x86.map b/libc/libc.x86.map
index bd74fbe..5f27643 100644
--- a/libc/libc.x86.map
+++ b/libc/libc.x86.map
@@ -1302,9 +1302,10 @@
 
 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 {