2 files changed, 5 insertions, 6 deletions
diff --git a/gnuradio-runtime/include/gnuradio/hier_block2.h b/gnuradio-runtime/include/gnuradio/hier_block2.h
index 69173becd6..fc81796a78 100644
--- a/gnuradio-runtime/include/gnuradio/hier_block2.h
+++ b/gnuradio-runtime/include/gnuradio/hier_block2.h
@@ -34,10 +34,8 @@ class GR_RUNTIME_API hier_block2 : public basic_block
 {
 private:
     friend class hier_block2_detail;
-    friend GR_RUNTIME_API hier_block2_sptr
-    make_hier_block2(const std::string& name,
-                     gr::io_signature::sptr input_signature,
-                     gr::io_signature::sptr output_signature);
+    template <typename T, typename... Args>
+    friend std::shared_ptr<T> gnuradio::make_block_sptr(Args&&... args);
 
     /*!
      * \brief Private implementation details of gr::hier_block2.
diff --git a/gnuradio-runtime/include/gnuradio/top_block.h b/gnuradio-runtime/include/gnuradio/top_block.h
index fd8ab66a94..12051e6f04 100644
--- a/gnuradio-runtime/include/gnuradio/top_block.h
+++ b/gnuradio-runtime/include/gnuradio/top_block.h
@@ -28,8 +28,9 @@ GR_RUNTIME_API top_block_sptr make_top_block(const std::string& name,
 class GR_RUNTIME_API top_block : public hier_block2
 {
 private:
-    friend GR_RUNTIME_API top_block_sptr make_top_block(const std::string& name,
-                                                        bool catch_exceptions);
+    template <typename T, typename... Args>
+    friend std::shared_ptr<T> gnuradio::make_block_sptr(Args&&... args);
+
 
     std::unique_ptr<top_block_impl> d_impl;