Fix debug runtime assert

diff --git a/simgear/props/PropertyInterpolationMgr.cxx b/simgear/props/PropertyInterpolationMgr.cxx
index ad8060e2f59f8d3bb0413cd23e5ba4dad5cc5d34..1e8ac02cb65d2b41f38d38b7cac55ea634a404a0 100644 (file)
--- a/simgear/props/PropertyInterpolationMgr.cxx
+++ b/simgear/props/PropertyInterpolationMgr.cxx
@@ -70,6 +70,12 @@ namespace simgear
           break;
         }
       }
+
+         // needed to avoid incrementing an invalid iterator when we
+         // erase the last interpolator
+         if (it == _interpolators.end()) {
+                 break;
+         }
     }
   }