don't try to backup sessions from older versions of ardour that are also read-only

git-svn-id: svn://localhost/ardour2/branches/3.0@12823 d708f5d6-7413-0410-9779-e7cbd77b26cf

diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 2f69ff2dee3dbd7d337bfe7d0596ce40d8b6debe..05aea88a464a8a709a0ff221c84cf6d3f6eda36e 100644 (file)
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -929,7 +929,7 @@ Session::load_state (string snapshot_name)
                }
        }
 
-       if (Stateful::loading_state_version < CURRENT_SESSION_FILE_VERSION) {
+       if (Stateful::loading_state_version < CURRENT_SESSION_FILE_VERSION && _writable) {
 
                sys::path backup_path(_session_dir->root_path());