Subject: flet not undone on lisp nesting error

From: Dan Davison <[email-masked]>
Date: Sun, 28 Feb 2010 21:30:49 -0500

If I trigger a lisp nesting error with an infinite recursion inside a
let and an flet binding, then the effects of the flet are not undone,
resulting in a change of binding at the top-level.

(defun g () 'g-orig)
(setq a 'a-orig)

(defun h ()
  (let ((a 'a-new))
    (flet ((g () 'g-new))
      (h))))
(h)   ;; <-- Lisp nesting exceeds `max-lisp-eval-depth'
(g)   ;; g-new ! 
a     ;; a-orig 

Dan

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
/usr/share/emacs/23.1/etc/DEBUG for instructions.

In GNU Emacs 23.1.1 (i486-pc-linux-gnu, GTK+ Version 2.18.3)
 of 2009-11-10 on vernadsky, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.10604000
configured using `configure  '--build=i486-linux-gnu' '--host=i486-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var/lib' '--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes' '--enable-locallisppath=/etc/emacs23:/etc/emacs:/usr/local/share/emacs/23.1/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.1/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/23.1/leim' '--with-x=yes' '--with-x-toolkit=gtk' '--with-toolkit-scroll-bars' 'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -g -O2' 'LDFLAGS=-g' 'CPPFLAGS=''

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  value of $LC_TIME: nil
  value of $LANG: en_GB.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
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<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <tab> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <tab> 
C-x C-s <up> <up> <f1> <up> M-g <return> 1 0 0 <return> 
<down> <down> <down> <return> <down> <return> <escape> 
SPC SPC <up> <down> <prior> <prior> <escape> <up> <return> 
<escape> <escape> <down> <return> <escape> <next> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <up> <up> <up> <prior> <prior> <next> 
<next> <escape> <down> <down> <f10> <down> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> <down> <down> <down> <down> <down> <next> <prior> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <down> <down> 
<down> <down> <down> <down> <down> <down> <down> <up> 
<up> <up> <up> <up> <up> <down> <return> <escape> <up> 
<up> <up> <up> <up> <up> <up> <up> <up> <up> <up> <up> 
<up> <up> <up> <prior> <prior> <down> <down> <escape> 
<escape> <next> <up> <escape> <escape> <next> <prior> 
<prior> <escape> <up> <down> q <return> 2 0 0 <return> 
C-s f l e t C-s C-s <down> <up> <up> <return> <escape> 
<down> C-SPC M-> M-w M-x r e p o r t <tab> b u <tab> 
<return>

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