From 193369dddc8adc492d3d98b6f1d00de11a31e9c4 Mon Sep 17 00:00:00 2001
From: David Kastrup <dak@gnu.org>
Date: Fri, 27 May 2016 10:20:18 +0200
Subject: [PATCH] Issue 4863: Protect Grob_interface<>::interface_symbol_

---
 lily/include/grob-interface.hh | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lily/include/grob-interface.hh b/lily/include/grob-interface.hh
index 9c3eadb4b0..bde5f5263d 100644
--- a/lily/include/grob-interface.hh
+++ b/lily/include/grob-interface.hh
@@ -21,6 +21,7 @@
 #define INTERFACE_HH
 
 #include "lily-guile.hh"
+#include "protected-scm.hh"
 
 class Grob;
 
@@ -57,14 +58,14 @@ private:
   friend bool has_interface(Grob *);
 
 private:
-  static SCM interface_symbol_;
+  static Protected_scm interface_symbol_;
   static char const *cxx_name_;
   static char const *description_;
   static char const *variables_;
 };
 
 template <class Interface>
-SCM Grob_interface<Interface>::interface_symbol_;
+Protected_scm Grob_interface<Interface>::interface_symbol_;
 
 #endif /* INTERFACE_HH */
 
-- 
2.39.2