Bind open-paren-in-column-0-is-defun-start to nil at some entry points.

* progmodes/cc-engine.el (c-invalidate-state-cache-1)
(c-parse-state-1, c-guess-basic-syntax):  Bind it here.
* progmodes/cc-mode.el (c-before-change, c-after-change)
(c-font-lock-fontify-region): Bind it here.

lisp/ChangeLog

+2014-01-19  Alan Mackenzie  <acm@muc.de>
+
+	Bind open-paren-in-column-0-is-defun-start to nil at some entry
+	points.
+	* progmodes/cc-engine.el (c-invalidate-state-cache-1)
+	(c-parse-state-1, c-guess-basic-syntax):  Bind it here.
+	* progmodes/cc-mode.el (c-before-change, c-after-change)
+	(c-font-lock-fontify-region): Bind it here.
+
 2014-01-19  Martin Rudalics  <rudalics@gmx.at>
 
 	* term.el (term-window-width): Call window-text-width instead of

lisp/progmodes/cc-engine.el

@@ -3183,7 +3183,8 @@ comment at the start of cc-engine.el for more info."
     ;; Truncate `c-state-cache' and set `c-state-cache-good-pos' to a value
     ;; below `here'.  To maintain its consistency, we may need to insert a new
     ;; brace pair.
-    (let ((here-bol (c-point 'bol here))
+    (let (open-paren-in-column-0-is-defun-start
+	  (here-bol (c-point 'bol here))
 	  too-high-pa		  ; recorded {/(/[ next above here, or nil.
 	  dropped-cons		  ; was the last removed element a brace pair?
 	  pa)
@@ -3254,6 +3255,7 @@ comment at the start of cc-engine.el for more info."
   ;; This function might do hidden buffer changes.
   (let* ((here (point))
 	 (here-bopl (c-point 'bopl))
+	 open-paren-in-column-0-is-defun-start
 	 strategy	     ; 'forward, 'backward etc..
 	 ;; Candidate positions to start scanning from:
 	 cache-pos	     ; highest position below HERE already existing in
@@ -9370,7 +9372,8 @@ comment at the start of cc-engine.el for more info."
     (c-save-buffer-state
 	((indent-point (point))
 	 (case-fold-search nil)
-	 ;; A whole ugly bunch of various temporary variables.  Have
+	 open-paren-in-column-0-is-defun-start
+	 ;; A whole ugly bunch of various temporary variables.	Have
 	 ;; to declare them here since it's not possible to declare
 	 ;; a variable with only the scope of a cond test and the
 	 ;; following result clauses, and most of this function is a

lisp/progmodes/cc-mode.el

@@ -1032,15 +1032,16 @@ Note that the style variables are always made local to the buffer."
 		      (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
-	    (mapc (lambda (fn)
-		    (funcall fn beg end))
-		  c-get-state-before-change-functions))
-	)))
-  ;; The following must be done here rather than in `c-after-change' because
-  ;; newly inserted parens would foul up the invalidation algorithm.
+			      (buffer-substring-no-properties beg end)))))))
+
+	  (if c-get-state-before-change-functions
+	      (let (open-paren-in-column-0-is-defun-start)
+		(mapc (lambda (fn)
+			(funcall fn beg end))
+		      c-get-state-before-change-functions)))
+	  )))
+    ;; 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))
 
 (defvar c-in-after-change-fontification nil)
@@ -1062,7 +1063,7 @@ Note that the style variables are always made local to the buffer."
   ;; 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)
+  (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.
@@ -1178,7 +1179,8 @@ Note that the style variables are always made local to the buffer."
   ;; 
   ;; Type a space in the first blank line, and the fontification of the next
   ;; line was fouled up by context fontification.
-  (let ((new-beg beg) (new-end end) new-region case-fold-search)
+  (let ((new-beg beg) (new-end end) new-region case-fold-search
+	open-paren-in-column-0-is-defun-start)
     (if c-in-after-change-fontification
 	(setq c-in-after-change-fontification nil)
       (save-restriction