Fix EscapeSequence::encode returning a StringRef pointing to stack memory.

include/cling/Utils/UTF8.h

@@ -10,8 +10,9 @@
 #ifndef CLING_UTILS_UTF8_H
 #define CLING_UTILS_UTF8_H
 
-#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/raw_ostream.h"
 #include <locale>
+#include <string>
 
 namespace cling {
 
@@ -64,6 +65,7 @@ namespace cling {
 
       public:
         EscapeSequence();
+
         ///\brief Encode the bytes from Str into a representation capable of
         /// being printed in the current locale without data loss.
         /// When Str begins with any of the C++ unicode string literal
@@ -71,8 +73,16 @@ namespace cling {
         ///
         /// \param [in] Str - Start of bytes to convert
         /// \param [in] N - Number of bytes to convert
+        /// \param [in] Output - Ouput stream to write to
         ///
-        llvm::StringRef encode(const char* const Str, size_t N);
+        /// \return 'Output' to allow: EscapeSequence().encode(...) << "";
+        ///
+        llvm::raw_ostream& encode(const char* const Str, size_t N,
+                                  llvm::raw_ostream& Output);
+
+        ///\brief Overload for above returning a std::string.
+        ///
+        std::string encode(const char* const Str, size_t N);
       };
     }
   }

lib/Interpreter/Value.cpp

@@ -250,8 +250,8 @@ namespace cling {
         case '\"':
           if (N > 2 && Data[N-1] == '\"') {
             // Drop the terminating " so Utf-8 errors can be detected ("\xeA")
-            Out << Type << ' '
-                << utils::utf8::EscapeSequence().encode(Data, N-1) << "\"\n";
+            Out << Type << ' ';
+            utils::utf8::EscapeSequence().encode(Data, N-1, Out) << "\"\n";
             return;
           }
         default:

lib/Utils/UTF8.cpp

@@ -7,11 +7,11 @@
 // LICENSE.TXT for details.
 //------------------------------------------------------------------------------
 
+#include "cling/Utils/Output.h"
 #include "cling/Utils/UTF8.h"
 
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/Format.h"
-#include "llvm/Support/raw_ostream.h"
 
 #ifdef LLVM_ON_WIN32
 #include <Shlwapi.h>
@@ -254,7 +254,8 @@ EscapeSequence::EscapeSequence() : m_Utf8Out(false) {
 #endif
 }
 
-llvm::StringRef EscapeSequence::encode(const char* const Start, size_t N) {
+llvm::raw_ostream& EscapeSequence::encode(const char* const Start, size_t N,
+                                          llvm::raw_ostream& Output) {
   const char* Ptr = Start;
   const char* const End = Start + N;
 
@@ -271,7 +272,7 @@ llvm::StringRef EscapeSequence::encode(const char* const Start, size_t N) {
 
     // Simple printable string, just return it now.
     if (isPrint)
-      return llvm::StringRef(Start, N);
+      return Output << llvm::StringRef(Start, N);
 
     Ptr = Start;
   } else {
@@ -305,7 +306,7 @@ llvm::StringRef EscapeSequence::encode(const char* const Start, size_t N) {
       }
     }
     if (Hex != kEnd)
-      return Strm.str();
+      return Output << Strm.str();
 
     Ptr = Start + LastGood;
     Dump.buf().resize(LastGood);
@@ -315,6 +316,13 @@ llvm::StringRef EscapeSequence::encode(const char* const Start, size_t N) {
   llvm::raw_svector_ostream Strm(Dump.buf());
   while (Ptr < End)
     Dump(Ptr, Strm, true);
+
+  return Output << Strm.str();
+}
+
+std::string EscapeSequence::encode(const char* const Start, size_t N) {
+  stdstrstream Strm;
+  encode(Start, N, Strm);
   return Strm.str();
 }