Wrong type argument: stringp, nil

[雨晗]

When I try to use gdb to debug my C programming. It said "Wrong type  
argument: stringp, nil


In GNU Emacs 22.0.50.1 (powerpc-apple-darwin8.5.0)
 of 2006-03-11 on mini.local
X server distributor `Apple Computers', version 10.4.6
configured using `configure '--prefix=/Applications/Emacs.app/ 
Contents/Resources' '--with-carbon' '--without-x' '--libexecdir=/ 
Volumes/Emacs/Emacs.app/Contents/MacOS/libexec' 'CFLAGS=-arch i386 - 
arch ppc -isysroot /Developer/SDKs/MacOSX10.4u.sdk -DUSE_ATSUI''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  locale-coding-system: chinese-iso-8bit
  default-enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  encoded-kbd-mode: t
  jabber-activity-mode: t
  show-paren-mode: t
  tooltip-mode: t
  auto-compression-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<return> <escape> x g d b <return> <backspace> 9 <return>
e x i t <return> C-c C-c q u i t <return> C-x k <return>
C-x 1 C-x C-f p 1 2 9 <backspace> <backspace> 3 9 .
p a <tab> <return> <escape> x g d b <return> <backspace>
<backspace> 3 9 <return> <help-echo> <down-mouse-1>
<drag-mouse-1> <help-echo> <down-mouse-1> <mouse-1>
<down-mouse-1> <mouse-movement> <mouse-movement> <drag-mouse-1>
<down-mouse-1> <mouse-movement> <mouse-movement> <drag-mouse-1>
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-movement>
<mouse-movement> <drag-mouse-1> <menu-bar> <edit> <copy>
<help-echo> <down-mouse-1> <mouse-movement> <mouse-movement>
<drag-mouse-1> <menu-bar> <edit> <copy> <help-echo>
<escape> x r e p o r t - e m <tab> b <tab> <return
>

Recent messages:
error in process filter: gdb-set-window-buffer: Wrong type argument:  
stringp, nil
error in process filter: Wrong type argument: stringp, nil
p139.pas has auto save data; consider M-x recover-this-file
Fontifying p139.pas... (regexps..........)
p139.pas has auto save data; consider M-x recover-this-file
Fontifying p139.pas... (regexps..........)
p139.pas has auto save data; consider M-x recover-this-file
error in process filter: gdb-set-window-buffer: Wrong type argument:  
stringp, nil
error in process filter: Wrong type argument: stringp, nil
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