diff --git a/builtin.c b/builtin.c
index d7ba82c..6b65806 100644
--- a/builtin.c
+++ b/builtin.c
@@ -4109,6 +4109,8 @@ do_typeof(int nargs)
 	else
 		dbg = NULL;
 	arg = POP();
+	printf("debug: typeof(%p) with type %d [%s] flags %d [%s]\n",
+	       arg, arg->type, nodetype2str(arg->type), arg->flags, flags2str(arg->flags));
 	switch (arg->type) {
 	case Node_var_array:
 		/* Node_var_array is never UPREF'ed */
diff --git a/interpret.h b/interpret.h
index d52d537..bf58ff3 100644
--- a/interpret.h
+++ b/interpret.h
@@ -737,6 +737,7 @@ mod:
 				*lhs = r;
 			} else {
 				r = POP_SCALAR();
+				printf("debug: popped scalar %p with type %d [%s] flags %d [%s]\n", r, r->type, nodetype2str(r->type), r->flags, flags2str(r->flags));
 				UNFIELD(*lhs, r);
 			}
 			break;