Add headerFileInfor

Author: devajithvs

interpreter/cling/lib/Interpreter/IncrementalParser.cpp

@@ -856,6 +856,7 @@ namespace cling {
   // Add the input to the memory buffer, parse it, and add it to the AST.
   IncrementalParser::EParseResult
   IncrementalParser::ParseInternal(llvm::StringRef input) {
+    llvm::errs() << "ParseInternal: " << input << "\n";
     if (input.empty()) return IncrementalParser::kSuccess;
 
     Sema& S = getCI()->getSema();
@@ -897,9 +898,15 @@ namespace cling {
     FileID FID;
     // Create FileEntry and FileID for the current buffer.
     // Enabling the completion point only works on FileEntries.
+    time_t FakeModTime = std::time(nullptr);
     FileEntryRef FE =
         SM.getFileManager().getVirtualFileRef(source_name.str(), InputSize,
-                                              0 /* mod time*/);
+                                              FakeModTime /* mod time*/);
+    // Force creation of HeaderFileInfo for the virtual file.
+    // This ensures that when the virtual file is used as the includer,
+    // Clang will find a valid HeaderFileInfo.
+    m_CI->getPreprocessor().getHeaderSearchInfo().getFileInfo(FE);
+
     SM.overrideFileContents(FE, std::move(MB));
     FID = SM.createFileID(FE, NewLoc, SrcMgr::C_User);
     if (CO.CodeCompletionOffset != -1) {
@@ -941,6 +948,7 @@ namespace cling {
     else if (Diags.getNumWarnings())
       return kSuccessWithWarnings;
 
+      llvm::errs() << "ParseInternal: done!\n";
     return kSuccess;
   }