Use the IDVal directly as there's no need to convert to std::string.
Pointed out by Chris!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117557 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index aa0f9f0..3243354 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -1279,10 +1279,10 @@
   StringRef Name;
 
   if (ParseIdentifier(Name))
-    return TokError("expected identifier after '" + Twine(IDVal.str()) + "'");
+    return TokError("expected identifier after '" + Twine(IDVal) + "'");
 
   if (getLexer().isNot(AsmToken::Comma))
-    return TokError("unexpected token in '" + Twine(IDVal.str()) + "'");
+    return TokError("unexpected token in '" + Twine(IDVal) + "'");
   Lex();
 
   return ParseAssignment(Name);