diff --git a/include/ion-bb-image-io/rt_file.h b/include/ion-bb-image-io/rt_file.h
index c06a1d6c..d2b9b1c1 100644
--- a/include/ion-bb-image-io/rt_file.h
+++ b/include/ion-bb-image-io/rt_file.h
@@ -623,7 +623,7 @@ int binaryloader_finished(halide_buffer_t* in0, halide_buffer_t* in1, halide_buf
             auto& r(Reader::get_instance(session_id, width, height, output_directory));
             auto finished_flag = r.get_finished();
            *reinterpret_cast<bool*>(finished->host) = finished_flag;
-           *reinterpret_cast<uint_32*>(bin_idx->host) = r.get_index();
+           *reinterpret_cast<uint32_t*>(bin_idx->host) = r.get_index();
            if (finished_flag) {
                r.close();
                r.release_instance(session_id);