diff --git a/main.py b/main.py
index b1c7ce8..b1c09c7 100755
--- a/main.py
+++ b/main.py
@@ -606,7 +606,7 @@ def main(argv):
 
         elif preproc == 'mcpp':
             preproc_cmdline += [
-                '-e', 'UTF-8', '-I-', '-N', '-3', '-j',
+                '-e', 'UTF-8', '-I-', '-N', '-2', '-3', '-j',
                 '-V199901L',
                 ]