In article <mailman.2795.1540562775.1284.bug-gnu-emacs@gnu.org> you
wrote:
This long-standing problem appears occasionally, and only disappears if
you kill the buffer completely, then reopen the file. I never got to
report it because I never could find steps to reproduce it… until now
:) Nvm the non-sense code, I reduced testcase as far as I managed.
# Steps to reproduce:
1. Save the following text in `test.cpp`
int main() {
puts(It's");
auto foo = []()-> void { };
puts("It's");
}
2. Open `emacs -Q ./test.cpp`
3. Now, the text lacks a quote in the first `puts(It's");`. Add it so
it looks like `puts("It's");`. Essentially, if you'd compile it with
g++, it lacks any syntax error besides `puts` being undeclared.
# Expected
The line with `auto foo…` is not red.
# Actual
The line with `auto foo…` (in particular) becomes red.
Thanks for taking the trouble to report this bug. Thanks even more for
condensing it down to a minimal test case.
The following patch should fix it. Would you please apply the patch,
recompile .../lisp/progmodes/cc-mode.el, load the new file in to your
Emacs (or restart Emacs), then try it out on your real C++ code. Then
please let me know whether it's working or not, and if not, how it's
going wrong. Thanks!
# Additional information
Emacs version GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu, GTK+
Version 3.22.30) of 2018-10-01, build with -flto.
diff -r 2f7029fa229d cc-mode.el
--- a/cc-mode.el Sun Oct 14 20:01:07 2018 +0000
+++ b/cc-mode.el Sun Oct 28 10:20:38 2018 +0000
@@ -1216,21 +1216,21 @@
(if (eq beg-literal-type 'string)
(setq c-new-BEG (min (car beg-limits) c-new-BEG))))
- ((< c-new-END (point-max))
- (goto-char (1+ c-new-END)) ; might be a newline.
+ ((< end (point-max))
+ (goto-char (1+ end)) ; might be a newline.
;; In the following regexp, the initial \n caters for a
newline getting
;; joined to a preceding \ by the removal of what comes between.
(re-search-forward
"[\n\r]?\\(\\\\\\(.\\|\n\\|\r\\)\\|[^\\\n\r]\\)*"
nil t)
;; We're at an EOLL or point-max.
- (setq c-new-END (min (1+ (point)) (point-max)))
- (goto-char c-new-END)
- (if (equal (c-get-char-property (1- (point)) 'syntax-table) '(15))
- (if (memq (char-before) '(?\n ?\r))
+ (setq c-new-END (max c-new-END (min (1+ (point)) (point-max))))
+ (if (equal (c-get-char-property (point) 'syntax-table) '(15))
+ (if (memq (char-after) '(?\n ?\r))
;; Normally terminated invalid string.
- (progn
+ (let ((eoll-1 (point)))
+ (forward-char)
(backward-sexp)
- (c-clear-char-property (1- c-new-END) 'syntax-table)
+ (c-clear-char-property eoll-1 'syntax-table)
(c-clear-char-property (point) 'syntax-table))
;; Opening " at EOB.
(c-clear-char-property (1- (point)) 'syntax-table))
@@ -1238,7 +1238,7 @@
;; Opening " on last line of text (without EOL).
(c-clear-char-property (point) 'syntax-table))))
- (t (goto-char c-new-END)
+ (t (goto-char end) ; point-max
(if (c-search-backward-char-property 'syntax-table '(15) c-new-BEG)
(c-clear-char-property (point) 'syntax-table))))
@@ -1327,9 +1327,9 @@
(while (progn
(setq s (parse-partial-sexp (point) c-new-END nil
nil s 'syntax-table))
- (and (not (nth 3 s))
- (< (point) c-new-END)
- (not (memq (char-before) c-string-delims)))))
+ (and (< (point) c-new-END)
+ (or (not (nth 3 s))
+ (not (memq (char-before)
c-string-delims))))))
;; We're at the start of a string.
(memq (char-before) c-string-delims)))
(if (c-unescaped-nls-in-string-p (1- (point)))