If we get an unknown or unimplemented opcode, say what it is

diff --git a/rts/Interpreter.c b/rts/Interpreter.c
index 81d4e38..94a0286 100644 (file)
--- a/rts/Interpreter.c
+++ b/rts/Interpreter.c
@@ -1249,7 +1249,8 @@ run_BCO:
            
            // Errors
        default: 
-           barf("interpretBCO: unknown or unimplemented opcode");
+           barf("interpretBCO: unknown or unimplemented opcode %d",
+                 (int)BCO_NEXT);
 
        } /* switch on opcode */
     }