From: Alan Mackenzie <acm@muc.de>
Date: Sat, 2 Jul 2022 16:12:59 +0000 (+0000)
Subject: CC Mode: Fix a c-backward-token-2 call wrongly jumping back over macros.
X-Git-Tag: emacs-28.1.91~72
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=dc3d01a5af;p=emacs.git

CC Mode: Fix a c-backward-token-2 call wrongly jumping back over macros.

This fixes bug #56256.

* lisp/progmodes/cc-fonts.el (c-font-lock-c++-lambda-captures): Replace a
c-backward-token-2, which could jump back too far leading to an infinite
loop, with a save-excursion to remember the point we've got to go back to.
---

diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el
index 63df267b43f..49e8763a28e 100644
--- a/lisp/progmodes/cc-fonts.el
+++ b/lisp/progmodes/cc-fonts.el
@@ -1826,7 +1826,7 @@ casts and declarations are fontified.  Used on level 2 and higher."
   ;; font-lock-keyword-face.  It always returns NIL to inhibit this and
   ;; prevent a repeat invocation.  See elisp/lispref page "Search-based
   ;; Fontification".
-  (let (mode capture-default id-start id-end declaration sub-begin sub-end)
+  (let (mode capture-default id-start id-end declaration sub-begin sub-end tem)
     (while (and (< (point) limit)
 		(search-forward "[" limit t))
       (when (progn (backward-char)
@@ -1838,15 +1838,18 @@ casts and declarations are fontified.  Used on level 2 and higher."
 			(char-after)))
 	;; Is the first element of the list a bare "=" or "&"?
 	(when mode
-	  (forward-char)
-	  (c-forward-syntactic-ws)
-	  (if (memq (char-after) '(?, ?\]))
-	      (progn
-		(setq capture-default mode)
-		(when (eq (char-after) ?,)
-		  (forward-char)
-		  (c-forward-syntactic-ws)))
-	    (c-backward-token-2)))
+	  (setq tem nil)
+	  (save-excursion
+	    (forward-char)
+	    (c-forward-syntactic-ws)
+	    (if (memq (char-after) '(?, ?\]))
+		(progn
+		  (setq capture-default mode)
+		  (when (eq (char-after) ?,)
+		    (forward-char)
+		    (c-forward-syntactic-ws))
+		  (setq tem (point)))))
+	  (if tem (goto-char tem)))
 
 	;; Go round the following loop once per captured item.  We use "\\s)"
 	;; rather than "\\]" here to avoid infinite looping in this situation: