diff --git a/gnuradio-runtime/include/gnuradio/host_buffer.h b/gnuradio-runtime/include/gnuradio/host_buffer.h
index a99519bfa99..61096ffbbff 100644
--- a/gnuradio-runtime/include/gnuradio/host_buffer.h
+++ b/gnuradio-runtime/include/gnuradio/host_buffer.h
@@ -95,7 +95,7 @@ class GR_RUNTIME_API host_buffer : public buffer_single_mapped
 
 private:
     // This is the simulated device buffer
-    std::unique_ptr<char> d_device_buf;
+    std::unique_ptr<char[]> d_device_buf;
     char* d_device_base;
 
     /*!