diff --git a/extra/time/macosx/platforms.txt b/extra/time/macosx/platforms.txt
new file mode 100644
index 0000000000..6e806f449e
--- /dev/null
+++ b/extra/time/macosx/platforms.txt
@@ -0,0 +1 @@
+macosx
diff --git a/extra/time/unix/platforms.txt b/extra/time/unix/platforms.txt
new file mode 100644
index 0000000000..509143d863
--- /dev/null
+++ b/extra/time/unix/platforms.txt
@@ -0,0 +1 @@
+unix
diff --git a/extra/time/windows/platforms.txt b/extra/time/windows/platforms.txt
new file mode 100644
index 0000000000..8e1a55995e
--- /dev/null
+++ b/extra/time/windows/platforms.txt
@@ -0,0 +1 @@
+windows