diff --git a/lib/cpp.py b/lib/cpp.py
index fd9ad4b..2a8ab73 100644
--- a/lib/cpp.py
+++ b/lib/cpp.py
@@ -117,6 +117,7 @@ def _is_dev_file(ent) -> bool:
         or ent.name.endswith(".la")
         or ent.name.endswith(".pc")
         or ent.name.endswith(".h")
+        or ent.name.endswith(".hpp")
         or ent.name.endswith(".cmake")
         or ent.name.endswith(".inc")
         or ("Makefile" in ent.name)