diff --git a/src/hb-blob.cc b/src/hb-blob.cc
index 59c833363..4cf6d1e54 100644
--- a/src/hb-blob.cc
+++ b/src/hb-blob.cc
@@ -26,7 +26,7 @@
 
 /* http://www.oracle.com/technetwork/articles/servers-storage-dev/standardheaderfiles-453865.html */
 #ifndef _POSIX_C_SOURCE
-#define _POSIX_C_SOURCE 199309L
+#define _POSIX_C_SOURCE 200809L
 #endif
 
 #include "hb-private.hh"