diff --git a/libstdc++-v3/include/bits/vector.tcc b/libstdc++-v3/include/bits/vector.tcc
index 44920a0549ab..4f4c366080be 100644
--- a/libstdc++-v3/include/bits/vector.tcc
+++ b/libstdc++-v3/include/bits/vector.tcc
@@ -934,7 +934,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 		const size_type __len =
 		  _M_check_len(__n, "vector::_M_range_insert");
 #if __cplusplus < 201103L
-		if (__len < (__n + (__old_start - __old_finish)))
+		if (__len < (__n + (__old_finish - __old_start)))
 		  __builtin_unreachable();
 #endif