2 files changed, 35 insertions, 20 deletions

diff --git a/src/core/model/Document.cpp b/src/core/model/Document.cpp
index 40c03ac..219e512 100644
--- a/src/core/model/Document.cpp
+++ b/src/core/model/Document.cpp
@@ -327,8 +327,10 @@ void DocumentEntity::addStructureNode(Handle<StructureNode> s, size_t i)
 		if (par != nullptr) {
 			if (par->isa(&RttiTypes::StructuredEntity)) {
 				par.cast<StructuredEntity>()->removeStructureNode(s);
-			} else {
+			} else if(par->isa(&RttiTypes::AnnotationEntity)){
 				par.cast<AnnotationEntity>()->removeStructureNode(s);
+			} else if(par->isa(&RttiTypes::Document)){
+				par.cast<Document>()->setRoot(nullptr);
 			}
 		}
 		s->setParent(subInst);
@@ -463,7 +465,7 @@ static bool matchStartAnchor(Handle<AnnotationClass> desc,
 template <typename Iterator>
 Rooted<Anchor> DocumentEntity::searchStartAnchorInField(
     Handle<AnnotationClass> desc, const std::string &name, Iterator begin,
-    Iterator end)
+    Iterator end, std::unordered_set<const DocumentEntity *> &visited)
 {
 	for (Iterator it = begin; it != end; it++) {
 		Handle<StructureNode> strct = *it;
@@ -478,7 +480,7 @@ Rooted<Anchor> DocumentEntity::searchStartAnchorInField(
 			// search downwards.
 			Rooted<Anchor> a =
 			    strct.cast<StructuredEntity>()->searchStartAnchorDownwards(
-			        desc, name);
+			        desc, name, visited);
 			if (a != nullptr) {
 				return a;
 			}
@@ -488,8 +490,12 @@ Rooted<Anchor> DocumentEntity::searchStartAnchorInField(
 }
 
 Rooted<Anchor> DocumentEntity::searchStartAnchorDownwards(
-    Handle<AnnotationClass> desc, const std::string &name)
+    Handle<AnnotationClass> desc, const std::string &name,
+    std::unordered_set<const DocumentEntity *> &visited)
 {
+	if (!visited.insert(this).second) {
+		return nullptr;
+	}
 	if (fields.empty()) {
 		return nullptr;
 	}
@@ -497,13 +503,17 @@ Rooted<Anchor> DocumentEntity::searchStartAnchorDownwards(
 	NodeVector<StructureNode> children = fields[fields.size() - 1];
 	// search it from back to front.
 	return searchStartAnchorInField(desc, name, children.rbegin(),
-	                                children.rend());
+	                                children.rend(), visited);
 }
 
 Rooted<Anchor> DocumentEntity::searchStartAnchorUpwards(
     Handle<AnnotationClass> desc, const std::string &name,
-    const DocumentEntity *child)
+    const DocumentEntity *child,
+    std::unordered_set<const DocumentEntity *> &visited)
 {
+	if (!visited.insert(this).second) {
+		return nullptr;
+	}
 	if (fields.empty()) {
 		return nullptr;
 	}
@@ -519,7 +529,8 @@ Rooted<Anchor> DocumentEntity::searchStartAnchorUpwards(
 	// to the child.
 	if (it != children.rend()) {
 		it++;
-		return searchStartAnchorInField(desc, name, it, children.rend());
+		return searchStartAnchorInField(desc, name, it, children.rend(),
+		                                visited);
 	}
 	throw OusiaException("Internal error: Child node not found in parent!");
 }
@@ -528,11 +539,13 @@ Rooted<Anchor> DocumentEntity::searchStartAnchor(size_t fieldIdx,
                                                  Handle<AnnotationClass> desc,
                                                  const std::string &name)
 {
+	std::unordered_set<const DocumentEntity *> visited;
+	visited.insert(this);
 	// get the correct field.
 	NodeVector<StructureNode> children = fields[fieldIdx];
 	// search it from back to front.
 	Rooted<Anchor> a = searchStartAnchorInField(desc, name, children.rbegin(),
-	                                            children.rend());
+	                                            children.rend(), visited);
 	// if we found the Anchor, return it.
 	if (a != nullptr) {
 		return a;
@@ -548,11 +561,11 @@ Rooted<Anchor> DocumentEntity::searchStartAnchor(size_t fieldIdx,
 	if (subInst->getParent()->isa(&RttiTypes::StructuredEntity)) {
 		return subInst->getParent()
 		    .cast<StructuredEntity>()
-		    ->searchStartAnchorUpwards(desc, name, this);
+		    ->searchStartAnchorUpwards(desc, name, this, visited);
 	}
 	if (subInst->getParent()->isa(&RttiTypes::AnnotationEntity)) {
 		subInst->getParent().cast<AnnotationEntity>()->searchStartAnchorUpwards(
-		    desc, name, this);
+		    desc, name, this, visited);
 	}
 	return nullptr;
 }
diff --git a/src/core/model/Document.hpp b/src/core/model/Document.hpp
index 8019379..6b2ae47 100644
--- a/src/core/model/Document.hpp
+++ b/src/core/model/Document.hpp
@@ -157,16 +157,18 @@ private:
 	void invalidateSubInstance();
 
 	template <typename Iterator>
-	Rooted<Anchor> searchStartAnchorInField(Handle<AnnotationClass> desc,
-	                                        const std::string &name,
-	                                        Iterator begin, Iterator end);
-
-	Rooted<Anchor> searchStartAnchorDownwards(Handle<AnnotationClass> desc,
-	                                          const std::string &name);
-
-	Rooted<Anchor> searchStartAnchorUpwards(Handle<AnnotationClass> desc,
-	                                        const std::string &name,
-	                                        const DocumentEntity *child);
+	Rooted<Anchor> searchStartAnchorInField(
+	    Handle<AnnotationClass> desc, const std::string &name, Iterator begin,
+	    Iterator end, std::unordered_set<const DocumentEntity *> &visited);
+
+	Rooted<Anchor> searchStartAnchorDownwards(
+	    Handle<AnnotationClass> desc, const std::string &name,
+	    std::unordered_set<const DocumentEntity *> &visited);
+
+	Rooted<Anchor> searchStartAnchorUpwards(
+	    Handle<AnnotationClass> desc, const std::string &name,
+	    const DocumentEntity *child,
+	    std::unordered_set<const DocumentEntity *> &visited);
 
 protected:
 	bool doValidate(Logger &logger) const;