Index: lib/Lex/Lexer.cpp
===================================================================
--- lib/Lex/Lexer.cpp
+++ lib/Lex/Lexer.cpp
@@ -1713,6 +1713,11 @@
                                          getLangOpts());
         if (!isIdentifierBody(Next)) {
           // End of suffix. Check whether this is on the whitelist.
+          if (getLangOpts().CPlusPlus1z && Chars == 2 && 
+              Buffer[0] == 's' && Buffer[1] == 'v') {
+            IsUDSuffix = true;
+            break;
+          }
           IsUDSuffix = (Chars == 1 && Buffer[0] == 's') ||
                        NumericLiteralParser::isValidUDSuffix(
                            getLangOpts(), StringRef(Buffer, Chars));