diff --git a/man2/fsync.2 b/man2/fsync.2
index a5b29e1dd..d1e34f361 100644
--- a/man2/fsync.2
+++ b/man2/fsync.2
@@ -51,12 +51,14 @@ Feature Test Macro Requirements for glibc (see
 .in
 .sp
 .BR fsync ():
-_BSD_SOURCE || _XOPEN_SOURCE
-.br
-         || /* since glibc 2.8: */ _POSIX_C_SOURCE\ >=\ 200112L
+    Glibc 2.16 and later:
+        No feature test macros need be defined
+    Glibc up to and including 2.15:
+        _BSD_SOURCE || _XOPEN_SOURCE
+            || /* since glibc 2.8: */ _POSIX_C_SOURCE\ >=\ 200112L
 .br
 .BR fdatasync ():
-_POSIX_C_SOURCE\ >=\ 199309L || _XOPEN_SOURCE\ >=\ 500
+    _POSIX_C_SOURCE\ >=\ 199309L || _XOPEN_SOURCE\ >=\ 500
 .SH DESCRIPTION
 .BR fsync ()
 transfers ("flushes") all modified in-core data of