diff --git a/src/plugins/projectexplorer/projectnodes.cpp b/src/plugins/projectexplorer/projectnodes.cpp
index 0750850339c..3b1d7c049b2 100644
--- a/src/plugins/projectexplorer/projectnodes.cpp
+++ b/src/plugins/projectexplorer/projectnodes.cpp
@@ -636,16 +636,6 @@ void FolderNode::compress()
     }
 }
 
-bool FolderNode::isAncesterOf(Node *n)
-{
-    if (n == this)
-        return true;
-    FolderNode *p = n->parentFolderNode();
-    while (p && p != this)
-        p = p->parentFolderNode();
-    return p == this;
-}
-
 bool FolderNode::replaceSubtree(Node *oldNode, std::unique_ptr<Node> &&newNode)
 {
     std::unique_ptr<Node> keepAlive;
diff --git a/src/plugins/projectexplorer/projectnodes.h b/src/plugins/projectexplorer/projectnodes.h
index 790112e1007..2357dc14098 100644
--- a/src/plugins/projectexplorer/projectnodes.h
+++ b/src/plugins/projectexplorer/projectnodes.h
@@ -244,8 +244,6 @@ public:
                        = [](const Utils::FileName &fn) { return std::make_unique<FolderNode>(fn); });
     void compress();
 
-    bool isAncesterOf(Node *n);
-
     // takes ownership of newNode.
     // Will delete newNode if oldNode is not a child of this node.
     bool replaceSubtree(Node *oldNode, std::unique_ptr<Node> &&newNode);