1 files changed, 28 insertions, 1 deletions

diff --git a/clang/include/clang/AST/ASTImporter.h b/clang/include/clang/AST/ASTImporter.h
index 4a55c120a45..38e9b03aea5 100644
--- a/clang/include/clang/AST/ASTImporter.h
+++ b/clang/include/clang/AST/ASTImporter.h
@@ -34,6 +34,7 @@ namespace clang {
 
 class ASTContext;
 class ASTImporterSharedState;
+class ASTUnit;
 class Attr;
 class CXXBaseSpecifier;
 class CXXCtorInitializer;
@@ -229,6 +230,11 @@ class TypeSourceInfo;
     /// The file managers we're importing to and from.
     FileManager &ToFileManager, &FromFileManager;
 
+    /// The ASTUnit for the From context, if any.
+    /// This is used to create a mapping of imported ('To') FileID's to the
+    /// original ('From') FileID and ASTUnit.
+    ASTUnit *FromUnit;
+
     /// Whether to perform a minimal import.
     bool Minimal;
 
@@ -277,6 +283,11 @@ class TypeSourceInfo;
 
     void AddToLookupTable(Decl *ToD);
 
+    ASTImporter(ASTContext &ToContext, FileManager &ToFileManager,
+                ASTContext &FromContext, FileManager &FromFileManager,
+                ASTUnit *FromUnit, bool MinimalImport,
+                std::shared_ptr<ASTImporterSharedState> SharedState);
+
   protected:
     /// Can be overwritten by subclasses to implement their own import logic.
     /// The overwritten method should call this method if it didn't import the
@@ -287,7 +298,6 @@ class TypeSourceInfo;
     virtual bool returnWithErrorInTest() { return false; };
 
   public:
-
     /// \param ToContext The context we'll be importing into.
     ///
     /// \param ToFileManager The file manager we'll be importing into.
@@ -307,6 +317,23 @@ class TypeSourceInfo;
                 ASTContext &FromContext, FileManager &FromFileManager,
                 bool MinimalImport,
                 std::shared_ptr<ASTImporterSharedState> SharedState = nullptr);
+    /// \param ToContext The context we'll be importing into.
+    ///
+    /// \param ToFileManager The file manager we'll be importing into.
+    ///
+    /// \param FromUnit Pointer to an ASTUnit that contains the context and
+    /// file manager to import from.
+    ///
+    /// \param MinimalImport If true, the importer will attempt to import
+    /// as little as it can, e.g., by importing declarations as forward
+    /// declarations that can be completed at a later point.
+    ///
+    /// \param SharedState The importer specific lookup table which may be
+    /// shared amongst several ASTImporter objects.
+    /// If not set then the original C/C++ lookup is used.
+    ASTImporter(ASTContext &ToContext, FileManager &ToFileManager,
+                ASTUnit &FromUnit, bool MinimalImport,
+                std::shared_ptr<ASTImporterSharedState> SharedState = nullptr);
 
     virtual ~ASTImporter();