diff --git a/cpp/scripts/include_checker.py b/cpp/scripts/include_checker.py
index ffd6c55c4b..6c1ad089e5 100644
--- a/cpp/scripts/include_checker.py
+++ b/cpp/scripts/include_checker.py
@@ -44,7 +44,7 @@ def list_all_source_file(file_regex, srcdirs):
     for srcdir in srcdirs:
         for root, dirs, files in os.walk(srcdir):
             for f in files:
-                if not re.search(file_regex, f) and re.search(file_regex, f):
+                if not re.search(exclusion_regex, root) and re.search(file_regex, f):
                     src = os.path.join(root, f)
                     all_files.append(src)
     return all_files