diff --git a/clang/test/Misc/dev-fd-fs.c b/clang/test/Misc/dev-fd-fs.c
index e35486ebe29a..fbc50fc685e7 100644
--- a/clang/test/Misc/dev-fd-fs.c
+++ b/clang/test/Misc/dev-fd-fs.c
@@ -1,5 +1,8 @@
 // Check that we can operate on files from /dev/fd.
 // REQUIRES: dev-fd-fs
+//
+// Currently, this only appears to work on Darwin's dev-fs.
+// REQUIRES: system-darwin
 
 
 // Check reading from named pipes. We cat the input here instead of redirecting