1 files changed, 9 insertions, 4 deletions
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 3d4e4cdd00..52eff1957d 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -1741,10 +1741,15 @@ void ASTDeclReader::UpdateDecl(Decl *D, const RecordData &Record) {
 
     case UPD_CXX_ADDED_ANONYMOUS_NAMESPACE: {
       NamespaceDecl *Anon = cast<NamespaceDecl>(Reader.GetDecl(Record[Idx++]));
-      if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(D))
-        TU->setAnonymousNamespace(Anon);
-      else
-        cast<NamespaceDecl>(D)->OrigOrAnonNamespace.setPointer(Anon);
+      // Guard against these being loaded out of original order. Don't use
+      // getNextNamespace(), since it tries to access the context and can't in
+      // the middle of deserialization.
+      if (!Anon->NextNamespace) {
+        if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(D))
+          TU->setAnonymousNamespace(Anon);
+        else
+          cast<NamespaceDecl>(D)->OrigOrAnonNamespace.setPointer(Anon);
+      }
       break;
     }
     }