bug#38155: 27.0.50; crash in write-region

[Richard Stallman]

I had a zip file in a buffer, after M-x base64-decode-region,
and tried to write it into a file.  I got this error.

Debugger entered--Lisp error: (wrong-type-argument number-or-marker-p nil)
  min(nil)
  apply(min nil)
  select-safe-coding-system-interactively(1 34936 (raw-text no-conversion) 
(no-conversion-multibyte) nil raw-text)
  select-safe-coding-system(1 34936 utf-8-unix nil "/home/rms/foo.zip")
  write-region(1 34936 "~/foo.zip" nil nil nil 1)



In GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 2.24.30)
 of 2019-10-02 built on freetop
Repository revision: 77207ca84184fc01428154c318b21c70ad150c01
Repository branch: master
System Description: Trisquel GNU/Linux Flidas (8.0)

Recent messages:
Mark set
Saved text from "UEsDBBQAAAAIAPErLU9uYDaVeIcAAI1eAQA0AAAA"
Mark set [3 times]
File /home/rms/foo.zip already exists; overwrite anyway? (y or n) y
apply: Wrong type argument: number-or-marker-p, nil
Debug on Error enabled globally
File /home/rms/foo.zip already exists; overwrite anyway? (y or n) y
Entering debugger...
Mark set
Back to top level

Configured using:
 'configure 'CFLAGS=-g -O0' --with-gnutls=ifavailable'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND GPM DBUS GSETTINGS GLIB NOTIFY
INOTIFY LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK2 X11 XDBE XIM THREADS PDUMPER GMP

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
  shell-dirtrack-mode: t
  gpm-mouse-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Load-path shadows:
None found.

Features:
(shadow emacsbug help-fns radix-tree cl-print debug backtrace
find-func url-http url url-proxy url-privacy url-expand url-history
mailcap url-auth url-gw nsm url-methods sh-script smie executable info
battery quail cal-move cal-menu calendar cal-loaddefs help-mode
thingatpt grep rect mule-util misearch multi-isearch dired-aux
epa-mail shell pcomplete shr url-cookie url-domsuf url-util svg xml
dom dabbrev rmailsum rmailkwd rmailout qp mailalias sendmail rmailmm
message rmc puny format-spec rfc822 mml mml-sec epa epg epg-config
gnus-util text-property-search time-date mm-decode mm-bodies mm-encode
mailabbrev gmm-utils mailheader mail-parse rfc2231 rmail
rmail-loaddefs rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils dired dired-loaddefs t-mouse term/linux view derived paren
cus-start cus-load advice finder-inf package easymenu browse-url
url-handlers url-parse auth-source cl-seq eieio eieio-core cl-macs
eieio-loaddefs password-cache json subr-x map url-vars seq byte-opt gv
bytecomp byte-compile compile comint ansi-color ring cconv cl-loaddefs
cl-lib tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel term/x-win x-win term/common-win x-dnd tool-bar
dnd fontset image regexp-opt fringe tabulated-list replace newcomment
text-mode elisp-mode lisp-mode prog-mode register page tab-bar
menu-bar rfn-eshadow isearch timer select scroll-bar mouse jit-lock
font-lock syntax facemenu font-core term/tty-colors frame cl-generic
cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet
lao korean japanese eucjp-ms cp51932 hebrew greek romanian slovak
czech european ethiopic indian cyrillic chinese composite charscript
charprop case-table epa-hook jka-cmpr-hook help simple abbrev obarray
minibuffer cl-preloaded nadvice loaddefs button faces cus-face
macroexp files text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget hashtable-print-readable backquote
threads dbusbind inotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty
make-network-process emacs)

Memory information:
((conses 16 404841 95478)
 (symbols 48 12765 29)
 (strings 32 50200 9227)
 (string-bytes 1 1783112)
 (vectors 16 31232)
 (vector-slots 8 1140551 232768)
 (floats 8 69 267)
 (intervals 56 96369 4434)
 (buffers 1000 175)
 (heap 1024 31593 2196))
[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]


-- 
Dr Richard Stallman
Founder, Free Software Foundation (https://gnu.org, https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)