Index: include/string
===================================================================
--- include/string
+++ include/string
@@ -4042,6 +4042,10 @@
 {
   inline namespace string_literals
   {
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wuser-defined-literals"
+#endif
     inline _LIBCPP_INLINE_VISIBILITY
     basic_string<char> operator "" s( const char *__str, size_t __len )
     {
@@ -4065,6 +4069,9 @@
     {
         return basic_string<char32_t> (__str, __len);
     }
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
   }
 }
 #endif
Index: include/string_view
===================================================================
--- include/string_view
+++ include/string_view
@@ -792,6 +792,10 @@
 {
   inline namespace string_view_literals
   {
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wuser-defined-literals"
+#endif
     inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
     basic_string_view<char> operator "" sv(const char *__str, size_t __len) _NOEXCEPT
     {
@@ -815,6 +819,9 @@
     {
         return basic_string_view<char32_t> (__str, __len);
     }
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#endif
   }
 }
 #endif