3 files changed, 24 insertions, 6 deletions
diff --git a/clang/lib/Sema/ParseAST.cpp b/clang/lib/Sema/ParseAST.cpp
index bb5acb0ee8d..d237f7539e4 100644
--- a/clang/lib/Sema/ParseAST.cpp
+++ b/clang/lib/Sema/ParseAST.cpp
@@ -29,14 +29,15 @@ using namespace clang;
 /// held by Ctx.
 ///
 void clang::ParseAST(Preprocessor &PP, ASTConsumer *Consumer,
-                     ASTContext &Ctx, bool PrintStats) {
+                     ASTContext &Ctx, bool PrintStats,
+                     bool CompleteTranslationUnit) {
   // Collect global stats on Decls/Stmts (until we have a module streamer).
   if (PrintStats) {
     Decl::CollectingStats(true);
     Stmt::CollectingStats(true);
   }
 
-  Sema S(PP, Ctx, *Consumer);
+  Sema S(PP, Ctx, *Consumer, CompleteTranslationUnit);
   Parser P(PP, S);
   PP.EnterMainSourceFile();
     
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index f11ce2043a8..403e8f60f56 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -151,12 +151,14 @@ void Sema::ActOnTranslationUnitScope(SourceLocation Loc, Scope *S) {
   Context.setObjCIdType(IdTypedef);
 }
 
-Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer)
+Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
+           bool CompleteTranslationUnit)
   : LangOpts(pp.getLangOptions()), PP(pp), Context(ctxt), Consumer(consumer),
     Diags(PP.getDiagnostics()),
     SourceMgr(PP.getSourceManager()), CurContext(0), PreDeclaratorDC(0),
     CurBlock(0), PackContext(0), IdResolver(pp.getLangOptions()),
-    GlobalNewDeleteDeclared(false) {
+    GlobalNewDeleteDeclared(false), 
+    CompleteTranslationUnit(CompleteTranslationUnit) {
   
   // Get IdentifierInfo objects for known functions for which we
   // do extra checking.  
@@ -216,6 +218,9 @@ void Sema::DeleteStmt(StmtTy *S) {
 /// translation unit when EOF is reached and all but the top-level scope is
 /// popped.
 void Sema::ActOnEndOfTranslationUnit() {
+  if (!CompleteTranslationUnit)
+    return;
+
   // C99 6.9.2p2:
   //   A declaration of an identifier for an object that has file
   //   scope without an initializer, and without a storage-class
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index f48e75afb35..d64228794bd 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -214,7 +214,18 @@ public:
   /// A flag to remember whether the implicit forms of operator new and delete
   /// have been declared.
   bool GlobalNewDeleteDeclared;
-  
+
+  /// \brief Whether the code handled by Sema should be considered a
+  /// complete translation unit or not.
+  ///
+  /// When true (which is generally the case), Sema will perform
+  /// end-of-translation-unit semantic tasks (such as creating
+  /// initializers for tentative definitions in C) once parsing has
+  /// completed. This flag will be false when building PCH files,
+  /// since a PCH file is by definition not a complete translation
+  /// unit.
+  bool CompleteTranslationUnit;
+
   /// ObjCMethodList - a linked list of methods with different signatures.
   struct ObjCMethodList {
     ObjCMethodDecl *Method;
@@ -239,7 +250,8 @@ public:
   /// Private Helper predicate to check for 'self'.
   bool isSelfExpr(Expr *RExpr);
 public:
-  Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer);
+  Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
+       bool CompleteTranslationUnit = true);
   ~Sema() {
     if (PackContext) FreePackedContext();
   }