From b2bcf6456c61c0e112b482bcc12dc32b93f83fa3 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sat, 26 Oct 2019 08:12:41 +0200
Subject: [PATCH] ASSERT_MSG: eval-apply

---
 src/eval-apply.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/eval-apply.c b/src/eval-apply.c
index 05f2d234..4bb60709 100644
--- a/src/eval-apply.c
+++ b/src/eval-apply.c
@@ -877,7 +877,11 @@ begin_expand:
               else if (TYPE (R1) == TPORT)
                 input = set_current_input_port (R1);
               else
-                assert_msg (0, "0");
+                {
+                  eputs ("begin_expand failed, R1=");
+                  display_error_ (R1);
+                  assert_msg (0, "begin-expand-boom 0");
+                }
 
               push_cc (input, R2, R0, cell_vm_return);
               x = read_input_file_env (R0);