Index: clang/lib/Lex/LiteralSupport.cpp
===================================================================
--- clang/lib/Lex/LiteralSupport.cpp
+++ clang/lib/Lex/LiteralSupport.cpp
@@ -787,10 +787,12 @@
   } else if (Pos == ThisTokEnd)
     return;
 
-  if (isDigitSeparator(*Pos))
+  if (isDigitSeparator(*Pos)) {
     PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Pos - ThisTokBegin),
             diag::err_digit_separator_not_between_digits)
       << IsAfterDigits;
+    hadError = true;
+  }
 }
 
 /// ParseNumberStartingWithZero - This method is called when the first character
Index: clang/test/Lexer/cxx1y_digit_separators.cpp
===================================================================
--- clang/test/Lexer/cxx1y_digit_separators.cpp
+++ clang/test/Lexer/cxx1y_digit_separators.cpp
@@ -51,6 +51,7 @@
   float u = 0x.'p1f; // expected-error {{hexadecimal floating literal requires a significand}}
   float v = 0e'f; // expected-error {{exponent has no digits}}
   float w = 0x0p'f; // expected-error {{exponent has no digits}}
+  float x = 0'e+1; // expected-error {{digit separator cannot appear at end of digit sequence}}
 }
 
 #line 123'456