diff --git a/librarymanager/config.rst b/librarymanager/config.rst
index a68ad2e6ad..fd47e63ca5 100644
--- a/librarymanager/config.rst
+++ b/librarymanager/config.rst
@@ -546,7 +546,7 @@ Project structure
     for item in env.get("CPPDEFINES", []):
         if isinstance(item, tuple) and item[0] == "HAL":
             env.Append(CPPPATH=[realpath(join("hal", item[1]))])
-            env.Replace(SRC_FILTER=["+<*>", "-<hal*>", "+<hal%s>" % item[1]])
+            env.Replace(SRC_FILTER=["+<*>", "-<hal*>", "+<hal/%s>" % item[1]])
             break
 
     # pass flags to a global build environment (for all libraries, etc)