Fix potential crash in snap_to_grid (grid-mark list is empty).

diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index c56cd94d1d9eeb25548830bf92f8830d5c114c92..d911cf648bdd4d244db53972ee15ebb0c46cbf0e 100644 (file)
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -2710,6 +2710,8 @@ check_best_snap ( samplepos_t presnap, samplepos_t &test, samplepos_t &dist, sam
 samplepos_t
 Editor::snap_to_grid (vector<ArdourCanvas::Ruler::Mark> marks, samplepos_t presnap, RoundMode direction)
 {
+       if  (marks.empty() ) return presnap;
+
        samplepos_t before;
        samplepos_t after;
        samplepos_t test;