diff --git a/lib/Makefile.am b/lib/Makefile.am
index f12e092..5f17fca 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -21,8 +21,11 @@
 PRECROSS_TARGET =
 
 if WITH_CPP
+# cpp dir is picked directly by plugin build
+if !WITH_PLUGIN
 SUBDIRS += cpp
 endif
+endif
 
 if WITH_C_GLIB
 SUBDIRS += c_glib