Reported by: 张海君 <netjune <at> icloud.com>
Date: Mon, 6 Apr 2015 10:11:02 UTC
Severity: normal
Done: Alan Mackenzie <acm <at> muc.de>
Bug is archived. No further changes may be made.
Message #14 received at 20266 <at> debbugs.gnu.org (full text, mbox):
From: Alan Mackenzie <acm <at> muc.de> To: 张海君 <netjune <at> icloud.com> Cc: 20266 <at> debbugs.gnu.org Subject: Re: bug#20266: Emacs doesn't respond when editing the attached c header file. Date: Tue, 21 Apr 2015 16:14:42 +0000
Hello, Netjune.
On Sun, Apr 12, 2015 at 10:15:15AM +0800, 张海君 wrote:
> > 在 2015年4月7日，23:16，Alan Mackenzie <acm <at> muc.de> 写道：
> > In article <mailman.71.1428315070.904.bug-gnu-emacs <at> gnu.org> you wrote:
> >> [-- text/plain, encoding 7bit, charset: us-ascii, 13 lines --]
> >> Emacs doesn't respond when editing the attached c header file.
> >> Emacs version: 24.4.
> >> ------------------------------------
> >> Run emacs with "emacs -Q test.h".
> >> M-x mark-whole-buffer
> >> M-x kill-ring-save
> >> M-x end-of-buffer
> >> M-x yank
> >> Then emacs doesn't respond for about 5 seconds.
> >> M-x scroll-down-command.
> >> Then emacs doesn't respond for about 5 seconds too.
> > Yes. This isn't good at all.
> >> M-x scroll-down-command.
> >> Then emacs doesn't respond for about 5 seconds too.
> > I can't actually reproduce this delay.
> Try do it more than 4 times, like: M-> M-v M-v M-v M-v M-v.
> The delay often happens at the first M-v, but not always.
> The delay is about 5 seconds on mac OSX (cpu: 1.4GHz), and is about 2 seconds on linux (cpu: 2.53Ghz).
After applying the patch below, I measured a single M-v from the end of
the buffer, and it took 0.14s. This is on GNU/Linux on a 5 year old PC
(2.6 GHz processor).
> Or try to input some text (like newline chars) at the end of buffer.
> I input a newline at the end of buffer, and emacs didn't respond about 2 seconds on linux.
Yes. That is a different kettle of fish altogether.
> After apply the patch, there is no delay after yank.
Thanks. With the following patch (instead of the first one) there
shouldn't be much delay with C-x u after having done the yank.
The patch is calculated in Emacs-24.4. Please try it out.
--- cc-mode.el.orig 2014-03-21 05:34:40.000000000 +0000
+++ cc-mode.el 2015-04-21 14:33:55.571993081 +0000
@@ -509,6 +509,14 @@
(set (make-local-variable 'comment-line-break-function)
'c-indent-new-comment-line)
+ ;; Prevent time-wasting activity on C-y.
+ (when (boundp 'yank-handled-properties)
+ (make-local-variable 'yank-handled-properties)
+ (let ((yank-cat-handler (assq 'category yank-handled-properties)))
+ (when yank-cat-handler
+ (setq yank-handled-properties (remq yank-cat-handler
+ yank-handled-properties)))))
+
;; For the benefit of adaptive file, which otherwise mis-fills.
(setq fill-paragraph-handle-comment nil)
@@ -831,6 +839,18 @@
(defvar c-old-EOM 0)
(make-variable-buffer-local 'c-old-EOM)
+(defun c-called-from-text-property-change-p ()
+ ;; Is the primitive which invoked `before-change-functions' or
+ ;; `after-change-functions' one which merely changes text properties? This
+ ;; function must be called directly from a member of one of the above hooks.
+ ;;
+ ;; In the following call, frame 0 is `backtrace-frame', frame 1 is
+ ;; `c-called-from-text-property-change-p', frame 2 is
+ ;; `c-before/after-change', frame 3 is the primitive invoking the change
+ ;; hook.
+ (memq (cadr (backtrace-frame 3))
+ '(put-text-property remove-list-of-text-properties)))
+
(defun c-extend-region-for-CPP (beg end)
;; Set c-old-BOM or c-old-EOM respectively to BEG, END, each extended to the
;; beginning/end of any preprocessor construct they may be in.
@@ -988,64 +1008,65 @@
;; it/them from the cache. Don't worry about being inside a string
;; or a comment - "wrongly" removing a symbol from `c-found-types'
;; isn't critical.
- (setq c-maybe-stale-found-type nil)
- (save-restriction
- (save-match-data
- (widen)
- (save-excursion
- ;; Are we inserting/deleting stuff in the middle of an identifier?
- (c-unfind-enclosing-token beg)
- (c-unfind-enclosing-token end)
- ;; Are we coalescing two tokens together, e.g. "fo o" -> "foo"?
- (when (< beg end)
- (c-unfind-coalesced-tokens beg end))
- ;; Are we (potentially) disrupting the syntactic context which
- ;; makes a type a type? E.g. by inserting stuff after "foo" in
- ;; "foo bar;", or before "foo" in "typedef foo *bar;"?
- ;;
- ;; We search for appropriate c-type properties "near" the change.
- ;; First, find an appropriate boundary for this property search.
- (let (lim
- type type-pos
- marked-id term-pos
- (end1
- (or (and (eq (get-text-property end 'face) 'font-lock-comment-face)
- (previous-single-property-change end 'face))
- end)))
- (when (>= end1 beg) ; Don't hassle about changes entirely in comments.
- ;; Find a limit for the search for a `c-type' property
- (while
- (and (/= (skip-chars-backward "^;{}") 0)
- (> (point) (point-min))
- (memq (c-get-char-property (1- (point)) 'face)
- '(font-lock-comment-face font-lock-string-face))))
- (setq lim (max (point-min) (1- (point))))
-
- ;; Look for the latest `c-type' property before end1
- (when (and (> end1 (point-min))
- (setq type-pos
- (if (get-text-property (1- end1) 'c-type)
- end1
- (previous-single-property-change end1 'c-type nil lim))))
- (setq type (get-text-property (max (1- type-pos) lim) 'c-type))
-
- (when (memq type '(c-decl-id-start c-decl-type-start))
- ;; Get the identifier, if any, that the property is on.
- (goto-char (1- type-pos))
- (setq marked-id
- (when (looking-at "\\(\\sw\\|\\s_\\)")
- (c-beginning-of-current-token)
- (buffer-substring-no-properties (point) type-pos)))
-
- (goto-char end1)
- (skip-chars-forward "^;{}") ; FIXME!!! loop for comment, maybe
- (setq lim (point))
- (setq term-pos
- (or (next-single-property-change end 'c-type nil lim) lim))
- (setq c-maybe-stale-found-type
- (list type marked-id
- type-pos term-pos
- (buffer-substring-no-properties type-pos term-pos)
+ (unless (c-called-from-text-property-change-p)
+ (setq c-maybe-stale-found-type nil)
+ (save-restriction
+ (save-match-data
+ (widen)
+ (save-excursion
+ ;; Are we inserting/deleting stuff in the middle of an identifier?
+ (c-unfind-enclosing-token beg)
+ (c-unfind-enclosing-token end)
+ ;; Are we coalescing two tokens together, e.g. "fo o" -> "foo"?
+ (when (< beg end)
+ (c-unfind-coalesced-tokens beg end))
+ ;; Are we (potentially) disrupting the syntactic context which
+ ;; makes a type a type? E.g. by inserting stuff after "foo" in
+ ;; "foo bar;", or before "foo" in "typedef foo *bar;"?
+ ;;
+ ;; We search for appropriate c-type properties "near" the change.
+ ;; First, find an appropriate boundary for this property search.
+ (let (lim
+ type type-pos
+ marked-id term-pos
+ (end1
+ (or (and (eq (get-text-property end 'face) 'font-lock-comment-face)
+ (previous-single-property-change end 'face))
+ end)))
+ (when (>= end1 beg) ; Don't hassle about changes entirely in comments.
+ ;; Find a limit for the search for a `c-type' property
+ (while
+ (and (/= (skip-chars-backward "^;{}") 0)
+ (> (point) (point-min))
+ (memq (c-get-char-property (1- (point)) 'face)
+ '(font-lock-comment-face font-lock-string-face))))
+ (setq lim (max (point-min) (1- (point))))
+
+ ;; Look for the latest `c-type' property before end1
+ (when (and (> end1 (point-min))
+ (setq type-pos
+ (if (get-text-property (1- end1) 'c-type)
+ end1
+ (previous-single-property-change end1 'c-type nil lim))))
+ (setq type (get-text-property (max (1- type-pos) lim) 'c-type))
+
+ (when (memq type '(c-decl-id-start c-decl-type-start))
+ ;; Get the identifier, if any, that the property is on.
+ (goto-char (1- type-pos))
+ (setq marked-id
+ (when (looking-at "\\(\\sw\\|\\s_\\)")
+ (c-beginning-of-current-token)
+ (buffer-substring-no-properties (point) type-pos)))
+
+ (goto-char end1)
+ (skip-chars-forward "^;{}") ; FIXME!!! loop for comment, maybe
+ (setq lim (point))
+ (setq term-pos
+ (or (next-single-property-change end 'c-type nil lim) lim))
+ (setq c-maybe-stale-found-type
+ (list type marked-id
+ type-pos term-pos
+ (buffer-substring-no-properties type-pos term-pos)
(buffer-substring-no-properties beg end)))))))
(if c-get-state-before-change-functions
@@ -1056,7 +1077,7 @@
)))
;; The following must be done here rather than in `c-after-change' because
;; newly inserted parens would foul up the invalidation algorithm.
- (c-invalidate-state-cache beg))
+ (c-invalidate-state-cache beg)))
(defvar c-in-after-change-fontification nil)
(make-variable-buffer-local 'c-in-after-change-fontification)
@@ -1077,49 +1098,51 @@
;; This calls the language variable c-before-font-lock-functions, if non nil.
;; This typically sets `syntax-table' properties.
- (c-save-buffer-state (case-fold-search open-paren-in-column-0-is-defun-start)
- ;; When `combine-after-change-calls' is used we might get calls
- ;; with regions outside the current narrowing. This has been
- ;; observed in Emacs 20.7.
- (save-restriction
- (save-match-data ; c-recognize-<>-arglists changes match-data
- (widen)
-
- (when (> end (point-max))
- ;; Some emacsen might return positions past the end. This has been
- ;; observed in Emacs 20.7 when rereading a buffer changed on disk
- ;; (haven't been able to minimize it, but Emacs 21.3 appears to
- ;; work).
- (setq end (point-max))
- (when (> beg end)
- (setq beg end)))
-
- ;; C-y is capable of spuriously converting category properties
- ;; c-</>-as-paren-syntax and c-cpp-delimiter into hard syntax-table
- ;; properties. Remove these when it happens.
- (c-clear-char-property-with-value beg end 'syntax-table
- c-<-as-paren-syntax)
- (c-clear-char-property-with-value beg end 'syntax-table
- c->-as-paren-syntax)
- (c-clear-char-property-with-value beg end 'syntax-table nil)
-
- (c-trim-found-types beg end old-len) ; maybe we don't need all of these.
- (c-invalidate-sws-region-after beg end)
- ;; (c-invalidate-state-cache beg) ; moved to `c-before-change'.
- (c-invalidate-find-decl-cache beg)
-
- (when c-recognize-<>-arglists
- (c-after-change-check-<>-operators beg end))
-
- ;; (c-new-BEG c-new-END) will be the region to fontify. It may become
- ;; larger than (beg end).
- (setq c-new-BEG beg
- c-new-END end)
- (setq c-in-after-change-fontification t)
- (save-excursion
- (mapc (lambda (fn)
- (funcall fn beg end old-len))
- c-before-font-lock-functions))))))
+ ;; (c-new-BEG c-new-END) will be the region to fontify. It may become
+ ;; larger than (beg end).
+ (setq c-new-BEG beg c-new-END end)
+
+ (unless (c-called-from-text-property-change-p)
+ (c-save-buffer-state (case-fold-search open-paren-in-column-0-is-defun-start)
+ ;; When `combine-after-change-calls' is used we might get calls
+ ;; with regions outside the current narrowing. This has been
+ ;; observed in Emacs 20.7.
+ (save-restriction
+ (save-match-data ; c-recognize-<>-arglists changes match-data
+ (widen)
+
+ (when (> end (point-max))
+ ;; Some emacsen might return positions past the end. This has been
+ ;; observed in Emacs 20.7 when rereading a buffer changed on disk
+ ;; (haven't been able to minimize it, but Emacs 21.3 appears to
+ ;; work).
+ (setq end (point-max))
+ (when (> beg end)
+ (setq beg end)))
+
+ ;; C-y is capable of spuriously converting category properties
+ ;; c-</>-as-paren-syntax and c-cpp-delimiter into hard syntax-table
+ ;; properties. Remove these when it happens.
+ (c-save-buffer-state ()
+ (c-clear-char-property-with-value beg end 'syntax-table
+ c-<-as-paren-syntax)
+ (c-clear-char-property-with-value beg end 'syntax-table
+ c->-as-paren-syntax)
+ (c-clear-char-property-with-value beg end 'syntax-table nil))
+
+ (c-trim-found-types beg end old-len) ; maybe we don't need all of these.
+ (c-invalidate-sws-region-after beg end)
+ ;; (c-invalidate-state-cache beg) ; moved to `c-before-change'.
+ (c-invalidate-find-decl-cache beg)
+
+ (when c-recognize-<>-arglists
+ (c-after-change-check-<>-operators beg end))
+
+ (setq c-in-after-change-fontification t)
+ (save-excursion
+ (mapc (lambda (fn)
+ (funcall fn beg end old-len))
+ c-before-font-lock-functions)))))))
(defun c-set-fl-decl-start (pos)
;; If the beginning of the line containing POS is in the middle of a "local"
--
Alan Mackenzie (Nuremberg, Germany).
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.