(c-in-knr-argdecl): Limit number of paren/bracket pairs parsed, to solve

performance problem.

1 files changed, 4 insertions, 2 deletions

diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el
index 6ccd41a164c..2007f8ef919 100644
--- a/lisp/progmodes/cc-engine.el
+++ b/lisp/progmodes/cc-engine.el
@@ -6336,7 +6336,8 @@ comment at the start of cc-engine.el for more info."
       ;; the searchable range.
       (let* ((macro-start (c-query-macro-start))
              (lim (max (or lim (point-min)) (or macro-start (point-min))))
-             before-lparen after-rparen)
+             before-lparen after-rparen
+             (pp-count-out 20)) ; Max number of paren/brace constructs before we give up
         (narrow-to-region lim (c-point 'eol))
 
         ;; Search backwards for the defun's argument list.  We give up if we
@@ -6358,7 +6359,8 @@ comment at the start of cc-engine.el for more info."
         ;; {
 
         (catch 'knr
-          (while t ; go round one paren/bracket construct each time round.
+          (while (> pp-count-out 0) ; go back one paren/bracket pair each time.
+            (setq pp-count-out (1- pp-count-out))
             (c-syntactic-skip-backward "^)]}")
             (cond ((eq (char-before) ?\))
                    (setq after-rparen (point)))