From 18331d00da7394f169b842f9e701568fede9b402 Mon Sep 17 00:00:00 2001 From: Alan Mackenzie Date: Mon, 30 Oct 2017 17:33:03 +0000 Subject: [PATCH] Fix "Args out of range" error in c-determine-limit. Fixes bug #28598. * lisp/progmodes/cc-engine.el (c-determine-limit-get-base): If the candidate position for BASE is below point-min, scan forward to the end of the current literal. (c-determine-limit): Add an extra arm to the final cond form, testing for BASE being at point-min. --- lisp/progmodes/cc-engine.el | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el index db201a6322f..6f39cc64338 100644 --- a/lisp/progmodes/cc-engine.el +++ b/lisp/progmodes/cc-engine.el @@ -5189,16 +5189,25 @@ comment at the start of cc-engine.el for more info." ;; Get a "safe place" approximately TRY-SIZE characters before START. ;; This defsubst doesn't preserve point. (let* ((pos (max (- start try-size) (point-min))) - (s (c-state-semi-pp-to-literal pos))) - (or (car (cddr s)) pos))) + (s (c-state-semi-pp-to-literal pos)) + (cand (or (car (cddr s)) pos))) + (if (>= cand (point-min)) + cand + (parse-partial-sexp pos start nil nil (car s) 'syntax-table) + (point)))) (defun c-determine-limit (how-far-back &optional start try-size) - ;; Return a buffer position HOW-FAR-BACK non-literal characters from START - ;; (default point). This is done by going back further in the buffer then - ;; searching forward for literals. The position found won't be in a - ;; literal. We start searching for the sought position TRY-SIZE (default - ;; twice HOW-FAR-BACK) bytes back from START. This function must be fast. - ;; :-) + ;; Return a buffer position HOW-FAR-BACK non-literal characters from + ;; START (default point). The starting position, either point or + ;; START may not be in a comment or string. + ;; + ;; The position found will not be before POINT-MIN and won't be in a + ;; literal. + ;; + ;; We start searching for the sought position TRY-SIZE (default + ;; twice HOW-FAR-BACK) bytes back from START. + ;; + ;; This function must be fast. :-) (save-excursion (let* ((start (or start (point))) (try-size (or try-size (* 2 how-far-back))) @@ -5254,6 +5263,8 @@ comment at the start of cc-engine.el for more info." (+ (car elt) (- count how-far-back))) ((eq base (point-min)) (point-min)) + ((> base (- start try-size)) ; Can only happen if we hit point-min. + (car elt)) (t (c-determine-limit (- how-far-back count) base try-size)))))) -- 2.39.5