diff --git a/Makefile.tpl b/Makefile.tpl
index 5cdc119..c0e0106 100644
--- a/Makefile.tpl
+++ b/Makefile.tpl
@@ -574,6 +574,7 @@ CXX_FOR_TARGET_FLAG_TO_PASS = \
 # really work, for C++ host programs can't depend on the current-stage
 # C++ target library.
 CXX_FOR_TARGET_FLAG_TO_PASS = \
+	"RAW_CXX_FOR_TARGET=$(RAW_CXX_FOR_TARGET)" \
 	$(shell if echo "$(CXX_FOR_TARGET)" | grep " -funconfigured-" >
/dev/null; then :; else echo '"CXX_FOR_TARGET=$(CXX_FOR_TARGET)"'; fi)
 @endif target-libstdc++-v3