diff --git a/build/bakefiles/files.bkl b/build/bakefiles/files.bkl
index 19c0060111..e8c4054036 100644
--- a/build/bakefiles/files.bkl
+++ b/build/bakefiles/files.bkl
@@ -1933,6 +1933,7 @@ IMPORTANT: please read docs/tech/tn0016.txt before modifying this file!
     src/cocoa/taskbar.mm
     src/cocoa/textctrl.mm
     src/cocoa/toolbar.mm
+    src/cocoa/tooltip.mm
     src/cocoa/toplevel.mm
     src/cocoa/utils.cpp
     src/cocoa/utilsexc.mm
diff --git a/src/cocoa/tooltip.mm b/src/cocoa/tooltip.mm
new file mode 100644
index 0000000000..8b13789179
--- /dev/null
+++ b/src/cocoa/tooltip.mm
@@ -0,0 +1 @@
+