From 4287d56bad5201cf0946526bb0e27c17426bd969 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Mattias=20Engdeg=C3=A5rd?= Date: Fri, 27 Jan 2023 17:21:28 +0100 Subject: [PATCH] Repair hideif regexp problems * lisp/progmodes/hideif.el (hif-white-regexp, hif-tokenize): Avoid superlinear backtracking behaviour by rewriting regexps to avoid nested repetitions and make positive progress each time. Use lazy matching of the innards of /*...*/ comments to avoid matching too much. --- lisp/progmodes/hideif.el | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/lisp/progmodes/hideif.el b/lisp/progmodes/hideif.el index 4405ce0fe04..836db83c2f3 100644 --- a/lisp/progmodes/hideif.el +++ b/lisp/progmodes/hideif.el @@ -555,8 +555,8 @@ that form should be displayed.") (defconst hif-line-concat "\\\\[ \t]*[\n\r]") ;; If `hif-white-regexp' is modified, `hif-tokenize' might need to be modified ;; accordingly. -(defconst hif-white-regexp (concat "\\(?:\\(?:[ \t]\\|/\\*.*\\*/\\)*" - "\\(?:" hif-line-concat "\\)?\\)*")) +(defconst hif-white-regexp (concat "\\(?:[ \t]\\|/\\*.*?\\*/" + "\\|\\(?:" hif-line-concat "\\)\\)*")) (defconst hif-define-regexp (concat hif-cpp-prefix "\\(define\\|undef\\)")) (defconst hif-id-regexp (concat "[[:alpha:]_][[:alnum:]_]*")) (defconst hif-etc-regexp "\\.\\.\\.") @@ -946,8 +946,8 @@ Assuming we've just performed a `hif-token-regexp' lookup." (let ((token-list nil) ;; Similar to `hif-white-regexp' but keep the spaces if there are (white-regexp (concat "\\(?:" - "\\(?:\\([ \t]+\\)\\|\\(?:/\\*.*\\*/\\)?\\)*" - "\\(?:" hif-line-concat "\\)?" + "\\([ \t]+\\)\\|/\\*.*?\\*/" + "\\|\\(?:" hif-line-concat "\\)" "\\)*")) token) (setq hif-simple-token-only t) -- 2.39.5