bug#39140: 28.0.50; gdb-mode incorrectly responds to C-d when a python interpreter is running

[Eli Zaretskii]

> From: Vladimir Nikishkin <lockywolf@gmail.com>
> Date: Wed, 15 Jan 2020 09:25:16 +0800
> 
> So, Emacs ships a GDB-mode, runnable by M-x gdb RET
> Inside this inferior gdb session, we can run a python
> interpreter by typing: pi RET
> 
> In GDB that is run inside a plain terminal, the C-d command
> (the EOF character) returns from python to the standard GDB
> prompt.
> 
> Not so in Emacs. If you type C-d, there is either just:
> `quit>'
> printed, and nothing else, or the line:
> `Use quit() or Ctrl-D (i.e. EOF) to exit'
> However, sending C-q C-d RET, or using the window menu
> `menu-bar signals eof' ends the whole GDB session.

Does the patch below fix the problem?

diff --git a/lisp/progmodes/gdb-mi.el b/lisp/progmodes/gdb-mi.el
index b08d487..d841f74 100644
--- a/lisp/progmodes/gdb-mi.el
+++ b/lisp/progmodes/gdb-mi.el
@@ -1001,8 +1001,10 @@ gdb-delchar-or-quit
        ;; Sending an EOF does not work with GDB-MI; submit an
        ;; explicit quit command.
        (progn
-         (insert "quit")
-         (comint-send-input t t))
+          (if (> gdb-control-level 0)
+              (process-send-eof proc)
+            (insert "quit")
+            (comint-send-input t t)))
       (delete-char arg))))
 
 (defvar gdb-define-alist nil "Alist of #define directives for GUD tooltips.")