diff --git a/Makefile.in b/Makefile.in
index 2f5be57ac3..bfdbf52f25 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -170,7 +170,7 @@ FLAGS_TO_PASS = \
 	"AR_FLAGS=$(AR_FLAGS)" \
 	"BISON=$(BISON)" \
 	"C++FLAGS=$(C++FLAGS)" \
-	"C++_FOR_BUILD=$(C++_FOR_BUILD)"
+	"C++_FOR_BUILD=$(C++_FOR_BUILD)" \
 	"CC=$(CC)" \
 	"CC_FOR_BUILD=$(CC_FOR_BUILD)" \
 	"CFLAGS=$(CFLAGS)" \