Fix assert string to be more informative.

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@146061 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Expression/DWARFExpression.cpp b/source/Expression/DWARFExpression.cpp
index a2fdc07..6ce8201 100644
--- a/source/Expression/DWARFExpression.cpp
+++ b/source/Expression/DWARFExpression.cpp
@@ -994,7 +994,7 @@
         default:
         {
             Host::SetCrashDescriptionWithFormat ("Unhandled DW_OP_XXX opcode: %d, add support for it.", op);
-            assert (!"Unhandled DW_OP_XXX opcode: %d, add support for it.");
+            assert (!"Unhandled DW_OP_XXX opcode - look for actual value in Crash Description string.");
         }
         break;
     }