Properly bracket concat of comment-start-skip (Bug#34805)

* lisp/emacs-lisp/smie.el (smie-indent-fixindent):
* lisp/cedet/semantic/doc.el (semantic-doc-snarf-comment-for-tag):
* lisp/progmodes/fortran.el (fortran-previous-statement)
(fortran-next-statement)
(fortran-fill-statement):
* lisp/progmodes/vhdl-mode.el (vhdl-beginning-of-statement): Bracket
comment-start-skip and comment-end-skip to avoid unexpected regexp
operator precedence.

4 files changed, 11 insertions, 7 deletions

diff --git a/lisp/cedet/semantic/doc.el b/lisp/cedet/semantic/doc.el
index 5611629c14d..4f98cf41027 100644
--- a/lisp/cedet/semantic/doc.el
+++ b/lisp/cedet/semantic/doc.el
@@ -103,7 +103,8 @@ If NOSNARF is `lex', then return the lex token."
             nil
           ;; ok, try to clean the text up.
           ;; Comment start thingy
-          (while (string-match (concat "^\\s-*" comment-start-skip) ct)
+          (while (string-match (concat "^\\s-*\\(?:" comment-start-skip "\\)")
+                               ct)
             (setq ct (concat (substring ct 0 (match-beginning 0))
                              (substring ct (match-end 0)))))
           ;; Arbitrary punctuation at the beginning of each line.
diff --git a/lisp/emacs-lisp/smie.el b/lisp/emacs-lisp/smie.el
index 92b639d71e2..e0293c3cbb4 100644
--- a/lisp/emacs-lisp/smie.el
+++ b/lisp/emacs-lisp/smie.el
@@ -1446,9 +1446,9 @@ in order to figure out the indentation of some other (further down) point."
   (and (smie-indent--bolp)
        (save-excursion
          (comment-normalize-vars)
-         (re-search-forward (concat comment-start-skip
+         (re-search-forward (concat "\\(?:" comment-start-skip "\\)"
                                     "fixindent"
-                                    comment-end-skip)
+                                    "\\(?:" comment-end-skip "\\)")
                             ;; 1+ to account for the \n comment termination.
                             (1+ (line-end-position)) t))
        (current-column)))
diff --git a/lisp/progmodes/fortran.el b/lisp/progmodes/fortran.el
index 152667040fa..f01e866f557 100644
--- a/lisp/progmodes/fortran.el
+++ b/lisp/progmodes/fortran.el
@@ -1275,7 +1275,8 @@ Directive lines are treated as comments."
                      (concat "[ \t]*"
                              (regexp-quote fortran-continuation-string)))
                     (looking-at "[ \t]*$\\| \\{5\\}[^ 0\n]\\|\t[1-9]")
-                    (looking-at (concat "[ \t]*" comment-start-skip)))))
+                    (looking-at (concat "[ \t]*\\(?:"
+                                        comment-start-skip "\\)")))))
     (cond ((and continue-test
                 (not not-first-statement))
            (message "Incomplete continuation statement."))
@@ -1298,7 +1299,8 @@ Directive lines are treated as comments."
                 (or (looking-at fortran-comment-line-start-skip)
                     (looking-at fortran-directive-re)
                     (looking-at "[ \t]*$\\|     [^ 0\n]\\|\t[1-9]")
-                    (looking-at (concat "[ \t]*" comment-start-skip)))))
+                    (looking-at (concat "[ \t]*\\(?:"
+                                        comment-start-skip "\\)")))))
     (if (not not-last-statement)
         'last-statement)))
 
@@ -2146,7 +2148,8 @@ Always returns non-nil (to prevent `fill-paragraph' being called)."
               (or (looking-at "[ \t]*$")
                   (looking-at fortran-comment-line-start-skip)
                   (and comment-start-skip
-                       (looking-at (concat "[ \t]*" comment-start-skip)))))
+                       (looking-at (concat "[ \t]*\\(?:"
+                                           comment-start-skip "\\)")))))
       (save-excursion
         ;; Find beginning of statement.
         (fortran-next-statement)
diff --git a/lisp/progmodes/vhdl-mode.el b/lisp/progmodes/vhdl-mode.el
index 1dc0c61d063..13d0cfa67e8 100644
--- a/lisp/progmodes/vhdl-mode.el
+++ b/lisp/progmodes/vhdl-mode.el
@@ -6699,7 +6699,7 @@ search, and an argument indicating an interactive call."
     (if (and interactive
              (or (nth 3 state)
                  (nth 4 state)
-                 (looking-at (concat "[ \t]*" comment-start-skip))))
+                 (looking-at (concat "[ \t]*\\(?:" comment-start-skip "\\)"))))
         (forward-sentence (- count))
       (while (> count 0)
         (vhdl-beginning-of-statement-1 lim)