Index: cfe/trunk/include/clang/Tooling/CompilationDatabase.h
===================================================================
--- cfe/trunk/include/clang/Tooling/CompilationDatabase.h
+++ cfe/trunk/include/clang/Tooling/CompilationDatabase.h
@@ -60,16 +60,6 @@
 
   /// The output file associated with the command.
   std::string Output;
-
-  /// \brief An optional mapping from each file's path to its content for all
-  /// files needed for the compilation that are not available via the file
-  /// system.
-  ///
-  /// Note that a tool implementation is required to fall back to the file
-  /// system if a source file is not provided in the mapped sources, as
-  /// compilation databases will usually not provide all files in mapped sources
-  /// for performance reasons.
-  std::vector<std::pair<std::string, std::string> > MappedSources;
 };
 
 /// \brief Interface for compilation databases.
Index: cfe/trunk/tools/libclang/CXCompilationDatabase.cpp
===================================================================
--- cfe/trunk/tools/libclang/CXCompilationDatabase.cpp
+++ cfe/trunk/tools/libclang/CXCompilationDatabase.cpp
@@ -145,36 +145,23 @@
 unsigned
 clang_CompileCommand_getNumMappedSources(CXCompileCommand CCmd)
 {
-  if (!CCmd)
-    return 0;
-
-  return static_cast<CompileCommand *>(CCmd)->MappedSources.size();
+  // Left here for backward compatibility. No mapped sources exists in the C++
+  // backend anymore.
+  return 0;
 }
 
 CXString
 clang_CompileCommand_getMappedSourcePath(CXCompileCommand CCmd, unsigned I)
 {
-  if (!CCmd)
-    return cxstring::createNull();
-
-  CompileCommand *Cmd = static_cast<CompileCommand *>(CCmd);
-
-  if (I >= Cmd->MappedSources.size())
-    return cxstring::createNull();
-
-  return cxstring::createRef(Cmd->MappedSources[I].first.c_str());
+  // Left here for backward compatibility. No mapped sources exists in the C++
+  // backend anymore.
+  return cxstring::createNull();
 }
 
 CXString
 clang_CompileCommand_getMappedSourceContent(CXCompileCommand CCmd, unsigned I)
 {
-  if (!CCmd)
-    return cxstring::createNull();
-
-  CompileCommand *Cmd = static_cast<CompileCommand *>(CCmd);
-
-  if (I >= Cmd->MappedSources.size())
-    return cxstring::createNull();
-
-  return cxstring::createRef(Cmd->MappedSources[I].second.c_str());
+  // Left here for backward compatibility. No mapped sources exists in the C++
+  // backend anymore.
+  return cxstring::createNull();
 }