Package: emacs;
Reported by: Gustav Hållberg <gustav <at> gmail.com>
Date: Sun, 7 Sep 2025 15:18:01 UTC
Severity: normal
Found in version 30.1
Message #14 received at 79403 <at> debbugs.gnu.org (full text, mbox):
From: Eli Zaretskii <eliz <at> gnu.org> To: Gustav Hållberg <gustav <at> gmail.com> Cc: 79403 <at> debbugs.gnu.org Subject: Re: bug#79403: 30.1; M-x gdb startup problem with (eq gdb-debuginfod-enable-setting 'ask) Date: Sat, 13 Sep 2025 17:07:28 +0300
> From: Gustav Hållberg <gustav <at> gmail.com>
> Date: Sat, 13 Sep 2025 12:25:52 +0200
> Cc: 79403 <at> debbugs.gnu.org
>
> Thanks. Does the patch below give good results?
>
> Yes but gud-filter-defer-flag seems to be a global so if you have several gdb sessions going they all get
> confused while waiting for the y-or-no-p.
>
> To test I did:
> 1. M-x gdb, start debugging process A, stop at breakpoint
> 2. M-x gdb, attach to process B, waiting at y-or-n-p
> 3. Type "step" in A's gdb window
> 4. Answer "y" to the y-or-n-p for B
>
> This sent output from A's gdb to B's gdb buffer!
>
> It seems gud-filter-defer-flag and gud-filter-pending-text should be buffer-local (or process properties?) to
> avoid this.
> But I don't know this code at all so...
>
> That said, your patch is definitely a big improvement and the above error case is a bit contrived :)
Thanks, how about the patch below?
diff --git a/lisp/progmodes/gdb-mi.el b/lisp/progmodes/gdb-mi.el
index 74dff32..ebaff4a2 100644
--- a/lisp/progmodes/gdb-mi.el
+++ b/lisp/progmodes/gdb-mi.el
@@ -1108,7 +1108,9 @@ gdb-init-1
;; trigger questions about debuginfod queries.
(if (eq gdb-debuginfod-enable 'ask)
(setq gdb-debuginfod-enable
- (y-or-n-p "Enable querying debuginfod servers for this session?")))
+ (let ((gud-filter-defer-flag t))
+ (y-or-n-p
+ "Enable querying debuginfod servers for this session?"))))
(gdb-input (format "-gdb-set debuginfod enabled %s"
(if gdb-debuginfod-enable "on" "off"))
'gdb-debuginfod-message)
diff --git a/lisp/progmodes/gud.el b/lisp/progmodes/gud.el
index 5980bc2..1d43028 100644
--- a/lisp/progmodes/gud.el
+++ b/lisp/progmodes/gud.el
@@ -793,6 +793,10 @@ gdb-first-prompt
(defvar gud-filter-pending-text nil
"Non-nil means this is text that has been saved for later in `gud-filter'.")
+(defvar gud-filter-defer-flag nil
+ "Non-nil means don't process anything from the debugger right now.
+It is saved for when this flag is not set.")
+
;; One of the nice features of GDB is its impressive support for
;; context-sensitive command completion. We preserve that feature
;; in the GUD buffer by using a GDB command designed just for Emacs.
@@ -2829,6 +2833,11 @@ gud-common-init
(if find-file (setq-local gud-find-file find-file))
(setq gud-last-last-frame nil)
+ ;; We need these to be local to the process's buffer so that we could
+ ;; defer processing output for each debugging session separately.
+ (make-local-variable 'gud-filter-defer-flag)
+ (make-local-variable 'gud-filter-pending-text)
+
(set-process-filter (get-buffer-process (current-buffer)) #'gud-filter)
(set-process-sentinel (get-buffer-process (current-buffer)) #'gud-sentinel)
(gud-set-buffer))
@@ -2837,34 +2846,32 @@ gud-set-buffer
(when (derived-mode-p 'gud-mode)
(setq gud-comint-buffer (current-buffer))))
-(defvar gud-filter-defer-flag nil
- "Non-nil means don't process anything from the debugger right now.
-It is saved for when this flag is not set.")
-
;; These functions are responsible for inserting output from your debugger
;; into the buffer. The hard work is done by the method that is
;; the value of gud-marker-filter.
(defun gud-filter (proc string)
;; Here's where the actual buffer insertion is done
- (let (output process-window)
- (if (buffer-name (process-buffer proc))
- (if gud-filter-defer-flag
- ;; If we can't process any text now,
- ;; save it for later.
- (setq gud-filter-pending-text
- (concat (or gud-filter-pending-text "") string))
-
- ;; If we have to ask a question during the processing,
- ;; defer any additional text that comes from the debugger
- ;; during that time.
- (let ((gud-filter-defer-flag t))
- ;; Process now any text we previously saved up.
- (if gud-filter-pending-text
- (setq string (concat gud-filter-pending-text string)
- gud-filter-pending-text nil))
+ (let ((proc-buf (process-buffer proc))
+ (cbuf (current-buffer))
+ output process-window)
+ (if (buffer-name proc-buf)
+ (with-current-buffer proc-buf
+ (if gud-filter-defer-flag
+ ;; If we can't process any text now,
+ ;; save it for later.
+ (setq gud-filter-pending-text
+ (concat (or gud-filter-pending-text "") string))
+
+ ;; If we have to ask a question during the processing,
+ ;; defer any additional text that comes from the debugger
+ ;; during that time.
+ (let ((gud-filter-defer-flag t))
+ ;; Process now any text we previously saved up.
+ (if gud-filter-pending-text
+ (setq string (concat gud-filter-pending-text string)
+ gud-filter-pending-text nil))
- (with-current-buffer (process-buffer proc)
;; If we have been so requested, delete the debugger prompt.
(save-restriction
(widen)
@@ -2887,23 +2894,22 @@ gud-filter
;; Let the comint filter do the actual insertion.
;; That lets us inherit various comint features.
- (comint-output-filter proc output))
-
- ;; Put the arrow on the source line.
- ;; This must be outside of the save-excursion
- ;; in case the source file is our current buffer.
- (if process-window
- (with-selected-window process-window
- (gud-display-frame))
- ;; We have to be in the proper buffer, (process-buffer proc),
- ;; but not in a save-excursion, because that would restore point.
- (with-current-buffer (process-buffer proc)
- (gud-display-frame))))
-
- ;; If we deferred text that arrived during this processing,
- ;; handle it now.
- (if gud-filter-pending-text
- (gud-filter proc ""))))))
+ (comint-output-filter proc output)
+
+ ;; Put the arrow on the source line.
+ ;; This must be outside of the save-excursion
+ ;; in case the source file is our current buffer.
+ (if process-window
+ (with-selected-window process-window
+ (gud-display-frame))
+ ;; We are in the proper buffer, (process-buffer proc),
+ ;; but not in a save-excursion, because that would restore point.
+ (gud-display-frame)))
+
+ ;; If we deferred text that arrived during this processing,
+ ;; handle it now.
+ (if gud-filter-pending-text
+ (gud-filter proc "")))))))
(defvar gud-minor-mode-type nil)
(defvar gud-overlay-arrow-position nil)
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.