5 files changed, 23 insertions, 15 deletions
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 9b507cfc5e..4c323da7ee 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -2361,8 +2361,15 @@ void RecordDecl::LoadFieldsFromExternalStorage() const {
   ExternalASTSource::Deserializing TheFields(Source);
 
   llvm::SmallVector<Decl*, 64> Decls;
-  if (Source->FindExternalLexicalDeclsBy<FieldDecl>(this, Decls))
+  LoadedFieldsFromExternalStorage = true;  
+  switch (Source->FindExternalLexicalDeclsBy<FieldDecl>(this, Decls)) {
+  case ELR_Success:
+    break;
+    
+  case ELR_AlreadyLoaded:
+  case ELR_Failure:
     return;
+  }
 
 #ifndef NDEBUG
   // Check that all decls we got were FieldDecls.
@@ -2370,8 +2377,6 @@ void RecordDecl::LoadFieldsFromExternalStorage() const {
     assert(isa<FieldDecl>(Decls[i]));
 #endif
 
-  LoadedFieldsFromExternalStorage = true;
-
   if (Decls.empty())
     return;
 
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index 7d146572bf..b2806f092c 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -839,12 +839,17 @@ DeclContext::LoadLexicalDeclsFromExternalStorage() const {
   // Notify that we have a DeclContext that is initializing.
   ExternalASTSource::Deserializing ADeclContext(Source);
 
+  // Load the external declarations, if any.
   llvm::SmallVector<Decl*, 64> Decls;
-  if (Source->FindExternalLexicalDecls(this, Decls))
-    return;
-
-  // There is no longer any lexical storage in this context
   ExternalLexicalStorage = false;
+  switch (Source->FindExternalLexicalDecls(this, Decls)) {
+  case ELR_Success:
+    break;
+    
+  case ELR_Failure:
+  case ELR_AlreadyLoaded:
+    return;
+  }
 
   if (Decls.empty())
     return;
diff --git a/lib/AST/ExternalASTSource.cpp b/lib/AST/ExternalASTSource.cpp
index f428318a21..b96d65a729 100644
--- a/lib/AST/ExternalASTSource.cpp
+++ b/lib/AST/ExternalASTSource.cpp
@@ -51,11 +51,11 @@ ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 
 void ExternalASTSource::MaterializeVisibleDecls(const DeclContext *DC) { }
 
-bool 
+ExternalLoadResult 
 ExternalASTSource::FindExternalLexicalDecls(const DeclContext *DC,
                                             bool (*isKindWeWant)(Decl::Kind),
                                          llvm::SmallVectorImpl<Decl*> &Result) {
-  return true;
+  return ELR_AlreadyLoaded;
 }
 
 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const { }
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index 13933b3eb3..a4ed5f4da4 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -4008,12 +4008,9 @@ Stmt *ASTReader::GetExternalDeclStmt(uint64_t Offset) {
   llvm_unreachable("Broken chain");
 }
 
-bool ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
+ExternalLoadResult ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
                                          bool (*isKindWeWant)(Decl::Kind),
                                          llvm::SmallVectorImpl<Decl*> &Decls) {
-  assert(DC->hasExternalLexicalStorage() &&
-         "DeclContext has no lexical decls in storage");
-
   // There might be lexical decls in multiple parts of the chain, for the TU
   // at least.
   // DeclContextOffsets might reallocate as we load additional decls below,
@@ -4038,7 +4035,7 @@ bool ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
   }
 
   ++NumLexicalDeclContextsRead;
-  return false;
+  return ELR_Success;
 }
 
 DeclContext::lookup_result
diff --git a/lib/Serialization/ChainedIncludesSource.cpp b/lib/Serialization/ChainedIncludesSource.cpp
index da5be957a5..3b7cd23b92 100644
--- a/lib/Serialization/ChainedIncludesSource.cpp
+++ b/lib/Serialization/ChainedIncludesSource.cpp
@@ -185,7 +185,8 @@ ChainedIncludesSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 void ChainedIncludesSource::MaterializeVisibleDecls(const DeclContext *DC) {
   return getFinalReader().MaterializeVisibleDecls(DC);
 }
-bool ChainedIncludesSource::FindExternalLexicalDecls(const DeclContext *DC,
+ExternalLoadResult 
+ChainedIncludesSource::FindExternalLexicalDecls(const DeclContext *DC,
                                       bool (*isKindWeWant)(Decl::Kind),
                                       llvm::SmallVectorImpl<Decl*> &Result) {
   return getFinalReader().FindExternalLexicalDecls(DC, isKindWeWant, Result);