diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index ac4a052e1291..1513561bbd44 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,9 @@
 2018-05-21  Jonathan Wakely  <jwakely@redhat.com>
 
+	PR libstdc++/85818
+	* testsuite/experimental/filesystem/path/preferred_separator.cc: Add
+	dg-require-filesystem-ts.
+
 	PR libstdc++/85843
 	* src/c++11/cow-stdexcept.cc (logic_error, runtime_error): Explicitly
 	initialize base class to avoid warnings.
diff --git a/libstdc++-v3/testsuite/experimental/filesystem/path/preferred_separator.cc b/libstdc++-v3/testsuite/experimental/filesystem/path/preferred_separator.cc
index b470e312bb15..5ca948dfaef8 100644
--- a/libstdc++-v3/testsuite/experimental/filesystem/path/preferred_separator.cc
+++ b/libstdc++-v3/testsuite/experimental/filesystem/path/preferred_separator.cc
@@ -17,6 +17,7 @@
 
 // { dg-options "-O0 -lstdc++fs -std=gnu++11" }
 // { dg-do link { target c++11 } }
+// { dg-require-filesystem-ts "" }
 
 #include <experimental/filesystem>