diff --git a/include/host-build.mk b/include/host-build.mk
index c54ee3755c..70bf6e5a39 100644
--- a/include/host-build.mk
+++ b/include/host-build.mk
@@ -69,7 +69,8 @@ HOST_CONFIGURE_ARGS = \
 
 HOST_MAKE_VARS = \
 	CFLAGS="$(HOST_CFLAGS)" \
-	CXXFLAGS="$(HOST_CPPFLAGS)" \
+	CPPFLAGS="$(HOST_CPPFLAGS)" \
+	CXXFLAGS="$(HOST_CXXFLAGS)" \
 	LDFLAGS="$(HOST_LDFLAGS)"
 
 HOST_MAKE_FLAGS =