Subject: Guile 2.9.7 regression: "duplicate" record field names
From: Göran Weinholt <[email-masked]>
To: [email-masked]
Date: Sat, 14 Dec 2019 14:31:10 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello schemers,

The following program works in Guile 2.2.6 (and other R6RS
implementations), but raises an exception in Guile 2.9.7. A field called
"name" exists in record type a and record type b, but there is no actual
naming conflict as I understand it.

--8<---------------cut here---------------start------------->8---
(import (rnrs))

(define-record-type a
  (fields name))

(define-record-type b
  (parent a)
  (fields name))

(let ((x (make-b 'a 'b)))
  (write (list (a-name x)
               (b-name x)))
  (newline))
--8<---------------cut here---------------end--------------->8---

It should print (a b). The backtrace:

--8<---------------cut here---------------start------------->8---
Backtrace:
In ice-9/boot-9.scm:
  1722:10  8 (with-exception-handler _ _ #:unwind? _ # _)
In unknown file:
           7 (apply-smob/0 #<thunk 56291f86b320>)
In ice-9/boot-9.scm:
    718:2  6 (call-with-prompt _ _ #<procedure default-prompt-handle?>)
In ice-9/eval.scm:
    619:8  5 (_ #(#(#<directory (guile-user) 56291f8eff00>)))
In ice-9/boot-9.scm:
   2792:4  4 (save-module-excursion _)
  4336:12  3 (_)
In /tmp/foo.sps:
      6:0  2 (_)
In ice-9/boot-9.scm:
  1090:10  1 (make-record-type b ((immutable name)) _ #:parent _ # _ ?)
  1073:12  0 (append-fields _ _)

ice-9/boot-9.scm:1073:12: In procedure append-fields:
duplicate field name
--8<---------------cut here---------------end--------------->8---

Regards,

-- 
Göran Weinholt   | https://weinholt.se/
Debian developer | 73 de SA6CJK