2 files changed, 20 insertions, 22 deletions
diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index 0d388c6d01e..0b342389a03 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -1584,7 +1584,20 @@ const char *Lexer::LexUDSuffix(Token &Result, const char *CurPtr) {
   if (isIdentifierHead(C)) {
     if (!getFeatures().CPlusPlus0x) {
       if (!isLexingRawMode())
-        Diag(CurPtr, diag::warn_cxx11_compat_user_defined_literal)
+        Diag(CurPtr,
+             C == '_' ? diag::warn_cxx11_compat_user_defined_literal
+                      : diag::warn_cxx11_compat_reserved_user_defined_literal)
+          << FixItHint::CreateInsertion(getSourceLocation(CurPtr), " ");
+      return CurPtr;
+    }
+
+    // C++11 [lex.ext]p10, [usrlit.suffix]p1: A program containing a ud-suffix
+    // that does not start with an underscore is ill-formed. As a conforming
+    // extension, we treat all such suffixes as if they had whitespace before
+    // them.
+    if (C != '_') {
+      if (!isLexingRawMode())
+        Diag(CurPtr, diag::ext_reserved_user_defined_literal)
           << FixItHint::CreateInsertion(getSourceLocation(CurPtr), " ");
       return CurPtr;
     }
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index abcaf983572..221cc6e53ee 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -9383,30 +9383,15 @@ FinishedParams:
     return true;
   }
 
-  StringRef LiteralName 
+  StringRef LiteralName
     = FnDecl->getDeclName().getCXXLiteralIdentifier()->getName();
   if (LiteralName[0] != '_') {
-    // C++0x [usrlit.suffix]p1:
-    //   Literal suffix identifiers that do not start with an underscore are 
-    //   reserved for future standardization.
-    bool IsHexFloat = true;
-    if (LiteralName.size() > 1 && 
-        (LiteralName[0] == 'P' || LiteralName[0] == 'p')) {
-      for (unsigned I = 1, N = LiteralName.size(); I < N; ++I) {
-        if (!isdigit(LiteralName[I])) {
-          IsHexFloat = false;
-          break;
-        }
-      }
-    }
-    
-    if (IsHexFloat)
-      Diag(FnDecl->getLocation(), diag::warn_user_literal_hexfloat)
-        << LiteralName;
-    else
-      Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved);
+    // C++11 [usrlit.suffix]p1:
+    //   Literal suffix identifiers that do not start with an underscore
+    //   are reserved for future standardization.
+    Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved);
   }
-  
+
   return false;
 }