Subject: Re: bug#52796: 28.0.90; Incorrect CC Mode fontification in frame.c

From: Alan Mackenzie <[email-masked]>
Date: Tue, 28 Dec 2021 20:30:18 +0000

Hello, Eli.

On Sat, Dec 25, 2021 at 20:23:25 +0200, Eli Zaretskii wrote:
> From: [email-masked]
> --text follows this line--
> To reproduce:

>   emacs -Q
>   C-x C-f src/frame.c
>   C-u 1262 M-g g

> Observe a bunch of function and macro calls fontified as if they were
> function names in function definitions.  For example, the call to
> create_tty_output, init_frame_faces, and (some) calls of FRAME_LINES.

Sorry about that.  There was an error in a cache, the cache that tracks
whether or not braces are at the top level.  In particular, this error
was triggered by the first "struct" keyword in

static struct frame *
make_terminal_frame (struct terminal *terminal)
{

where it was failing to recognise the "*" as "cancelling" the
expectation of braces as part of the struct construct.

The patch below should fix the problem.  If you want to try it out,
please do.  Otherwise I'll commit it to the release branch if I don't
hear from you within a few days.

> In GNU Emacs 28.0.90 (build 35, i686-pc-mingw32)
>  of 2021-12-25 built on HOME-C4E4A596F7
> Repository revision: c09ad0cabde922374c1a34350595a3141ab7f806
> Repository branch: emacs-28
> Windowing system distributor 'Microsoft Corp.', version 5.1.2600
> System Description: Microsoft Windows XP Service Pack 3 (v5.1.0.2600)

[ .... ]

diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el
index d37a50997a..d289148874 100644
--- a/lisp/progmodes/cc-engine.el
+++ b/lisp/progmodes/cc-engine.el
@@ -6139,7 +6139,7 @@ c-update-brace-stack
 	  (setq s (cons -1 (cdr s))))
 	 ((and (equal match ",")
 	       (eq (car s) -1)))	; at "," in "class foo : bar, ..."
-	 ((member match '(";" "," ")"))
+	 ((member match '(";" "*" "," "("))
 	  (when (and s (cdr s) (<= (car s) 0))
 	    (setq s (cdr s))))
 	 ((c-keyword-member kwd-sym 'c-flat-decl-block-kwds)
diff --git a/lisp/progmodes/cc-langs.el b/lisp/progmodes/cc-langs.el
index 53f6206a82..85cc887110 100644
--- a/lisp/progmodes/cc-langs.el
+++ b/lisp/progmodes/cc-langs.el
@@ -3180,8 +3180,8 @@ c-populate-syntax-table
       (append
        (c-lang-const c-flat-decl-block-kwds)
        (if (c-lang-const c-recognize-<>-arglists)
-	   '("{" "}" ";" "," ")" ":" "<")
-	 '("{" "}" ";" "," ")" ":")))))
+	   '("{" "}" ";" "*" "," ")" ":" "<")
+	 '("{" "}" ";" "*" "," ")" ":")))))
 (c-lang-defvar c-brace-stack-thing-key (c-lang-const c-brace-stack-thing-key))
 
 (c-lang-defconst c-brace-stack-no-semi-key

-- 
Alan Mackenzie (Nuremberg, Germany).