diff --git a/dlls/fusion/fusion.c b/dlls/fusion/fusion.c
index 6c0bc008cd6..f9d57d19c73 100644
--- a/dlls/fusion/fusion.c
+++ b/dlls/fusion/fusion.c
@@ -51,6 +51,15 @@ HRESULT WINAPI ClearDownloadCache(void)
     return E_NOTIMPL;
 }
 
+/******************************************************************
+ *  CopyPDBs   (FUSION.@)
+ */
+HRESULT WINAPI CopyPDBs(void *unknown)
+{
+    FIXME("(%p) stub!\n", unknown);
+    return E_NOTIMPL;
+}
+
 /******************************************************************
  *  CreateInstallReferenceEnum   (FUSION.@)
  */
diff --git a/dlls/fusion/fusion.spec b/dlls/fusion/fusion.spec
index 264aff70959..f3a89507617 100644
--- a/dlls/fusion/fusion.spec
+++ b/dlls/fusion/fusion.spec
@@ -1,4 +1,4 @@
-@ stub CopyPDBs
+@ stdcall CopyPDBs(ptr)
 @ stdcall ClearDownloadCache()
 @ stdcall CreateApplicationContext(ptr ptr)
 @ stdcall CreateAssemblyCache(ptr long)