Add :link (custom-group-link font-lock-faces) to defgroup.
[bpt/emacs.git] / lisp / progmodes / fortran.el
index f921e59..65e7b89 100644 (file)
@@ -1,11 +1,11 @@
 ;;; fortran.el --- Fortran mode for GNU Emacs
 
-;; Copyright (c) 1986, 93, 94, 95, 97, 98, 99, 2000
-;;   Free Software Foundation, Inc.
+;; Copyright (C) 1986, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001,
+;;               2002, 2003, 2004, 2005  Free Software Foundation, Inc.
 
 ;; Author: Michael D. Prange <prange@erl.mit.edu>
-;; Maintainer: Dave Love <fx@gnu.org>
-;; Keywords: languages
+;; Maintainer: Glenn Morris <rgm@gnu.org>
+;; Keywords: fortran, languages
 
 ;; This file is part of GNU Emacs.
 
@@ -21,8 +21,8 @@
 
 ;; You should have received a copy of the GNU General Public License
 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
-;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
 
 ;;; Commentary:
 
@@ -30,7 +30,9 @@
 ;;
 ;; Note that it is for editing Fortran77 or Fortran90 fixed source
 ;; form.  For editing Fortran 90 free format source, use `f90-mode'
-;; (f90.el).
+;; (f90.el).  It is meant to support the GNU Fortran language
+;; implemented by g77 (its extensions to Fortran77 and
+;; interpretations, e.g. of blackslash in strings).
 
 ;;; History:
 
 ;; * Implement insertion and removal of statement continuations in
 ;;   mixed f77/f90 style, with the first `&' past column 72 and the
 ;;   second in column 6.
-;; * Support any other extensions to f77 grokked by GNU Fortran.
+;; * Support any other extensions to f77 grokked by GNU Fortran I've missed.
+
+(eval-when-compile                     ; silence compiler
+  (defvar dabbrev-case-fold-search)
+  (defvar font-lock-syntactic-keywords)
+  (defvar gud-find-expr-function)
+  (defvar imenu-case-fold-search)
+  (defvar imenu-syntax-alist))
+
 
 (defgroup fortran nil
-  "Fortran mode for Emacs"
+  "Major mode for editing fixed format Fortran code."
+  :link '(custom-group-link :tag "Font Lock Faces group" font-lock-faces)
   :link '(custom-manual "(emacs)Fortran")
   :group 'languages)
 
 (defgroup fortran-indent nil
-  "Indentation variables in Fortran mode"
+  "Indentation variables in Fortran mode."
   :prefix "fortran-"
-  :group 'fortran)
+  :group  'fortran)
 
 (defgroup fortran-comment nil
-  "Comment-handling variables in Fortran mode"
+  "Comment-handling variables in Fortran mode."
   :prefix "fortran-"
-  :group 'fortran)
+  :group  'fortran)
 
 
 ;;;###autoload
 (defcustom fortran-tab-mode-default nil
   "*Default tabbing/carriage control style for empty files in Fortran mode.
-A value of t specifies tab-digit style of continuation control.
+A non-nil value specifies tab-digit style of continuation control.
 A value of nil specifies that continuation lines are marked
 with a character in column 6."
-  :type 'boolean
+  :type  'boolean
   :group 'fortran-indent)
 
-;; Buffer local, used to display mode line.
-(defcustom fortran-tab-mode-string nil
-  "String to appear in mode line when TAB format mode is on."
-  :type '(choice (const nil) string)
+(defcustom fortran-tab-mode-string "/t"
+  "*String to appear in mode line in TAB format buffers."
+  :type  'string
   :group 'fortran-indent)
-(make-variable-buffer-local 'fortran-tab-mode-string)
 
 (defcustom fortran-do-indent 3
   "*Extra indentation applied to DO blocks."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-if-indent 3
-  "*Extra indentation applied to IF blocks."
-  :type 'integer
+  "*Extra indentation applied to IF, SELECT CASE and WHERE blocks."
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-structure-indent 3
   "*Extra indentation applied to STRUCTURE, UNION, MAP and INTERFACE blocks."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-continuation-indent 5
-  "*Extra indentation applied to Fortran continuation lines."
-  :type 'integer
+  "*Extra indentation applied to continuation lines."
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-comment-indent-style 'fixed
   "*How to indent comments.
-nil forces comment lines not to be touched,
-'fixed makes fixed comment indentation to `fortran-comment-line-extra-indent'
-columns beyond `fortran-minimum-statement-indent-fixed' (for
-`indent-tabs-mode' of nil) or `fortran-minimum-statement-indent-tab' (for
-`indent-tabs-mode' of t), and 'relative indents to current
-Fortran indentation plus `fortran-comment-line-extra-indent'."
-  :type '(radio (const :tag "Untouched" nil) (const fixed) (const relative))
+nil forces comment lines not to be touched;
+`fixed' indents to `fortran-comment-line-extra-indent' columns beyond
+  `fortran-minimum-statement-indent-fixed' (if `indent-tabs-mode' nil), or
+  `fortran-minimum-statement-indent-tab' (if `indent-tabs-mode' non-nil);
+`relative' indents to current Fortran indentation plus
+  `fortran-comment-line-extra-indent'."
+  :type  '(radio (const :tag "Untouched" nil) (const fixed) (const relative))
   :group 'fortran-indent)
 
 (defcustom fortran-comment-line-extra-indent 0
   "*Amount of extra indentation for text within full-line comments."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent
   :group 'fortran-comment)
 
@@ -124,8 +133,8 @@ Fortran indentation plus `fortran-comment-line-extra-indent'."
   "*Delimiter inserted to start new full-line comment.
 You might want to change this to \"*\", for instance."
   :version "21.1"
-  :type 'string
-  :group 'fortran-comment)
+  :type    'string
+  :group   'fortran-comment)
 
 ;; This used to match preprocessor lines too, but that messes up
 ;; filling and doesn't seem to be necessary.
@@ -133,17 +142,26 @@ You might want to change this to \"*\", for instance."
   "^[CcDd*!]\\(\\([^ \t\n]\\)\\2+\\)?[ \t]*"
   "*Regexp to match the start of a full-line comment."
   :version "21.1"
-  :type 'regexp
-  :group 'fortran-comment)
+  :type    'regexp
+  :group   'fortran-comment)
+
+(defcustom fortran-directive-re
+  "^[ \t]*#.*"
+  "*Regexp to match a directive line.
+The matching text will be fontified with `font-lock-keyword-face'.
+The matching line will be given zero indentation."
+  :version "22.1"
+  :type    'regexp
+  :group   'fortran-indent)
 
 (defcustom fortran-minimum-statement-indent-fixed 6
   "*Minimum statement indentation for fixed format continuation style."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-minimum-statement-indent-tab (max tab-width 6)
   "*Minimum statement indentation for TAB format continuation style."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent)
 
 ;; Note that this is documented in the v18 manuals as being a string
@@ -152,226 +170,247 @@ You might want to change this to \"*\", for instance."
 (defcustom fortran-comment-indent-char " "
   "*Single-character string inserted for Fortran comment indentation.
 Normally a space."
-  :type 'string
+  :type  'string
   :group 'fortran-comment)
 
 (defcustom fortran-line-number-indent 1
   "*Maximum indentation for Fortran line numbers.
 5 means right-justify them within their five-column field."
-  :type 'integer
+  :type  'integer
   :group 'fortran-indent)
 
 (defcustom fortran-check-all-num-for-matching-do nil
   "*Non-nil causes all numbered lines to be treated as possible DO loop ends."
-  :type 'boolean
+  :type  'boolean
   :group 'fortran)
 
 (defcustom fortran-blink-matching-if nil
-  "*Non-nil causes \\[fortran-indent-line] on ENDIF statement to blink on matching IF.
+  "*Non-nil causes \\[fortran-indent-line] on ENDIF to blink on matching IF.
 Also, from an ENDDO statement blink on matching DO [WHILE] statement."
-  :type 'boolean
+  :type  'boolean
   :group 'fortran)
 
 (defcustom fortran-continuation-string "$"
   "*Single-character string used for Fortran continuation lines.
 In fixed format continuation style, this character is inserted in
 column 6 by \\[fortran-split-line] to begin a continuation line.
-Also, if \\[fortran-indent-line] finds this at the beginning of a line, it will
-convert the line into a continuation line of the appropriate style.
-Normally $."
-  :type 'string
+Also, if \\[fortran-indent-line] finds this at the beginning of a
+line, it will convert the line into a continuation line of the
+appropriate style. Normally $."
+  :type  'string
   :group 'fortran)
 
 (defcustom fortran-comment-region "c$$$"
   "*String inserted by \\[fortran-comment-region] at start of each \
 line in region."
-  :type 'string
+  :type  'string
   :group 'fortran-comment)
 
 (defcustom fortran-electric-line-number t
-  "*Non-nil causes line number digits to be moved to the correct \
-column as typed."
-  :type 'boolean
+  "*Non-nil causes line numbers to be moved to the correct column as typed."
+  :type  'boolean
   :group 'fortran)
 
-(defvar fortran-column-ruler-fixed
+(defcustom fortran-column-ruler-fixed
   "0   4 6  10        20        30        40        5\
 0        60        70\n\
 \[   ]|{   |    |    |    |    |    |    |    |    \
 \|    |    |    |    |}\n"
   "String displayed above current line by \\[fortran-column-ruler].
-This variable used in fixed format mode.")
+This variable is used in fixed format mode.
+See the variable `fortran-column-ruler-tab' for TAB format mode."
+  :type  'string
+  :group 'fortran)
 
-(defvar fortran-column-ruler-tab
+(defcustom fortran-column-ruler-tab
   "0       810        20        30        40        5\
 0        60        70\n\
 \[   ]|  { |    |    |    |    |    |    |    |    \
 \|    |    |    |    |}\n"
   "String displayed above current line by \\[fortran-column-ruler].
-This variable used in TAB format mode.")
+This variable is used in TAB format mode.
+See the variable `fortran-column-ruler-fixed' for fixed format mode."
+  :type  'string
+  :group 'fortran)
 
-(defvar fortran-analyze-depth 100
-  "Number of lines to scan to determine whether to use fixed or TAB \
-format style.")
+(defcustom fortran-analyze-depth 100
+  "Number of lines to scan to identify fixed or TAB format style."
+  :type  'integer
+  :group 'fortran)
 
 (defcustom fortran-break-before-delimiters t
-  "*Non-nil causes filling to break lines before delimiters."
-  :type 'boolean
+  "*Non-nil causes filling to break lines before delimiters.
+Delimiters are characters matching the regexp `fortran-break-delimiters-re'."
+  :type  'boolean
   :group 'fortran)
 
-(defvar fortran-mode-syntax-table
-  (let ((table (make-syntax-table)))
-    ;; We might like `;' to be punctuation (g77 multi-statement
-    ;; lines), but that screws abbrevs.
-    (modify-syntax-entry ?\; "w" table)
-    (modify-syntax-entry ?\r " " table)
-    (modify-syntax-entry ?+ "." table)
-    (modify-syntax-entry ?- "." table)
-    (modify-syntax-entry ?= "." table)
-    (modify-syntax-entry ?* "." table)
-    (modify-syntax-entry ?/ "." table)
-    (modify-syntax-entry ?\' "\"" table)
-    (modify-syntax-entry ?\" "\"" table)
-    (modify-syntax-entry ?\\ "\\" table)
-    ;; This might be better as punctuation, as for C, but this way you
-    ;; can treat floating-point numbers as symbols.
-    (modify-syntax-entry ?. "_" table) ; e.g. `a.ne.b'
-    (modify-syntax-entry ?_ "_" table)
-    (modify-syntax-entry ?$ "_" table) ; esp. VMSisms
-    (modify-syntax-entry ?\! "<" table)
-    (modify-syntax-entry ?\n ">" table)
-    table)
-  "Syntax table in use in Fortran mode buffers.")
+(defconst fortran-break-delimiters-re "[-+*/><=, \t]"
+  "Regexp matching delimiter characters at which lines may be broken.
+There are certain tokens comprised entirely of characters
+matching this regexp that should not be split, and these are
+specified by the constant `fortran-no-break-re'.")
+
+;; The ">=", etc F77 extensions are supported by g77.
+(defconst fortran-no-break-re
+  (regexp-opt '("**" "//" "=>" ">=" "<=" "==" "/=") 'paren)
+  "Regexp specifying where not to break lines when filling.
+This regexp matches certain tokens comprised entirely of
+characters matching the regexp `fortran-break-delimiters-re' that should
+not be split by filling.  Each element is assumed to be two
+characters long.")
 
-;; Comments are real pain in Fortran because there is no way to
-;; represent the standard comment syntax in an Emacs syntax table.
-;; (We can do so for F90-style).  Therefore an unmatched quote in a
-;; standard comment will throw fontification off on the wrong track.
-;; So we do syntactic fontification with regexps.
+(defcustom fortran-mode-hook nil
+  "Hook run when entering Fortran mode."
+  :type  'hook
+  :group 'fortran)
 
-(defvar fortran-font-lock-keywords-1 nil
+\f
+(defvar fortran-if-start-re "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?if[ \t]*("
+  "Regexp matching the start of an IF statement.")
+
+(defvar fortran-end-prog-re1
+  "end\
+\\([ \t]*\\(program\\|subroutine\\|function\\|block[ \t]*data\\)\\>\
+\\([ \t]*\\(\\sw\\|\\s_\\)+\\)?\\)?"
+  "Regexp possibly matching the end of a subprogram.")
+
+(defvar fortran-end-prog-re
+  (concat "^[ \t0-9]*" fortran-end-prog-re1)
+  "Regexp possibly matching the end of a subprogram, from the line start.
+See also `fortran-end-prog-re1'.")
+
+(defconst fortran-type-types
+  (concat "\\<"
+          (mapconcat 'identity          ; " " -> "[ \t]*"
+                     (split-string
+                      (regexp-opt
+                       (let ((simple-types
+                              '("character" "byte" "integer" "logical"
+                                "none" "real" "complex"
+                                "double precision" "double complex"))
+                             (structured-types '("structure" "union" "map"))
+                             (other-types '("record" "dimension"
+                                            "parameter" "common" "save"
+                                            "external" "intrinsic" "data"
+                                            "equivalence")))
+                         (append
+                          (mapcar (lambda (x) (concat "implicit " x))
+                                  simple-types)
+                          simple-types
+                          (mapcar (lambda (x) (concat "end " x))
+                                  structured-types)
+                          structured-types
+                          other-types)) 'paren))
+                     "[ \t]*") "\\>")
+  "Regexp matching Fortran types.")
+
+(defvar fortran-font-lock-keywords-1
+  ;; Program, subroutine and function declarations, plus calls.
+  '(("\\<\\(block[ \t]*data\\|call\\|entry\\|function\\|\
+program\\|subroutine\\)\\>[ \t]*\\(\\sw+\\)?"
+     (1 font-lock-keyword-face)
+     (2 font-lock-function-name-face nil t)))
   "Subdued level highlighting for Fortran mode.")
 
-(defvar fortran-font-lock-keywords-2 nil
+(defvar fortran-font-lock-keywords-2
+  (append fortran-font-lock-keywords-1
+          (list
+           ;; Fontify all type specifiers (must be first - see below).
+           (cons fortran-type-types 'font-lock-type-face)
+           ;; Builtin keywords (except logical, do and goto - see below).
+           (concat "\\<" (regexp-opt
+                          '("continue" "format" "end" "enddo"
+                            "if" "then" "else" "endif" "elseif"
+                            "while" "inquire" "stop" "return"
+                            "include" "open" "close" "read"
+                            "write" "format" "print" "select" "case"
+                            "cycle" "exit" "rewind" "backspace"
+                            "where" "elsewhere")
+                          'paren) "\\>")
+           ;; Builtin operators.
+           (concat "\\." (regexp-opt
+                          '("and" "or" "not" "lt" "le" "eq" "ge"
+                            "gt" "ne" "true" "false")
+                          'paren) "\\.")
+           ;; do/goto keywords and targets, and goto tags.
+           '("\\<\\(do\\|go *to\\)\\>[ \t]*\\([0-9]+\\)?"
+             (1 font-lock-keyword-face)
+             (2 font-lock-constant-face nil t))
+           '("^ *\\([0-9]+\\)" . font-lock-constant-face)))
   "Medium level highlighting for Fortran mode.")
 
-(defvar fortran-font-lock-keywords-3 nil
+(defvar fortran-font-lock-keywords-3
+  (append
+   fortran-font-lock-keywords-1
+   ;; All type specifiers plus their declared items.
+   (list
+    (list (concat fortran-type-types "[ \t(/]*\\(*\\)?")
+          ;; Type specifier.
+          '(1 font-lock-type-face)
+          ;; Declaration item (or just /.../ block name).
+          `(font-lock-match-c-style-declaration-item-and-skip-to-next
+            ;; Start after any *(...) expression.
+            (condition-case nil
+                (and (match-beginning ,(1+ (regexp-opt-depth
+                                            fortran-type-types)))
+                     (forward-sexp)
+                     (forward-sexp))
+              (error nil))
+            ;; No need to clean up.
+            nil
+            ;; Fontify as a variable name, functions fontified elsewhere.
+            (1 font-lock-variable-name-face nil t))))
+   ;; Things extra to `fortran-font-lock-keywords-3' (must be done first).
+   (list
+    ;; Goto-like `err=label'/`end=label' in read/write statements.
+    '(", *\\(e\\(nd\\|rr\\)\\)\\> *\\(= *\\([0-9]+\\)\\)?"
+      (1 font-lock-keyword-face) (4 font-lock-constant-face nil t))
+    ;; Standard continuation character and in a TAB-formatted line.
+    '("^ \\{5\\}\\([^ 0\n]\\)" 1 font-lock-string-face)
+    '("^\t\\([1-9]\\)"         1 font-lock-string-face))
+   `((,fortran-directive-re (0 font-lock-keyword-face t)))
+   ;; `fortran-font-lock-keywords-2' without types (see above).
+   (cdr (nthcdr (length fortran-font-lock-keywords-1)
+                fortran-font-lock-keywords-2)))
   "Gaudy level highlighting for Fortran mode.")
 
-(defvar fortran-font-lock-syntactic-keywords nil
+(defvar fortran-font-lock-keywords-4
+  (append fortran-font-lock-keywords-3
+          (list (list
+                 (concat "\\<"
+                         (regexp-opt
+                          '("int" "ifix" "idint" "real" "float" "sngl"
+                            "dble" "cmplx" "ichar" "char" "aint" "dint"
+                            "anint" "dnint" "nint" "idnint" "iabs" "abs"
+                            "dabs" "cabs" "mod" "amod" "dmod" "isign"
+                            "sign" "dsign" "idim" "dim" "ddim" "dprod"
+                            "max" "max0" "amax1" "dmax1" "amax0" "max1"
+                            "min0" "amin1" "dmin1" "amin0" "min1" "len"
+                            "index" "lge" "lgt" "lle" "llt" "aimag"
+                            "conjg" "sqrt" "dsqrt" "csqrt" "exp" "dexp"
+                            "cexp" "log" "alog" "dlog" "clog" "log10"
+                            "alog10" "dlog10" "sin" "dsin" "csin" "cos"
+                            "dcos" "ccos" "tan" "dtan" "asin" "dasin"
+                            "acos" "dacos" "atan" "datan" "atan2" "datan2"
+                            "sinh" "dsinh" "cosh" "dcosh" "tanh" "dtanh")
+                          'paren) "[ \t]*(") '(1 font-lock-builtin-face))))
+  "Maximum highlighting for Fortran mode.
+Consists of level 3 plus all other intrinsics not already highlighted.")
+
+;; Comments are real pain in Fortran because there is no way to
+;; represent the standard comment syntax in an Emacs syntax table.
+;; (We can do so for F90-style).  Therefore an unmatched quote in a
+;; standard comment will throw fontification off on the wrong track.
+;; So we do syntactic fontification with regexps.
+(defvar fortran-font-lock-syntactic-keywords
+  '(("^[cd\\*]" 0 (11))
+    ("^[^cd\\*\t\n].\\{71\\}\\([^\n]+\\)" 1 (11)))
   "`font-lock-syntactic-keywords' for Fortran.
 These get fixed-format comments fontified.")
 
-(let ((comment-chars "cd\\*")          ; `d' for `debugging' comments
-      (fortran-type-types
-       (eval-when-compile
-        (let ((re (regexp-opt
-                   (let ((simple-types
-                          '("character" "byte" "integer" "logical"
-                            "none" "real" "complex"
-                            "double precision" "double complex"))
-                         (structured-types '("structure" "union" "map"))
-                         (other-types '("record" "dimension"
-                                        "parameter" "common" "save"
-                                        "external" "intrinsic" "data"
-                                        "equivalence")))
-                     (append
-                      (mapcar (lambda (x) (concat "implicit " x))
-                              simple-types)
-                      simple-types
-                      (mapcar (lambda (x) (concat "end " x))
-                              structured-types)
-                      structured-types
-                      other-types)))))
-          ;; In the optimized regexp above, replace spaces by a
-          ;; regexp for optional whitespace; regexp-opt would have
-          ;; escaped that.
-          (mapconcat #'identity (split-string re) "[ \t]*"))))
-      (fortran-keywords
-       (eval-when-compile
-         (regexp-opt '("continue" "format" "end" "enddo" "if" "then"
-                       "else" "endif" "elseif" "while" "inquire" "stop"
-                       "return" "include" "open" "close" "read" "write"
-                       "format" "print" "select" "case" "cycle" "exit"))))
-      (fortran-logicals
-       (eval-when-compile
-         (regexp-opt '("and" "or" "not" "lt" "le" "eq" "ge" "gt" "ne"
-                       "true" "false")))))
-  (setq fortran-font-lock-syntactic-keywords
-       ;; Fixed format comments.  (!-style handled normally.)
-       (list
-        (list (concat "^[" comment-chars "]") 0 '(11))
-        (list (concat "^[^" comment-chars "\t\n]" ".\\{71\\}"
-                      "\\([^\n]+\\)")
-              1 '(11))))
-  (setq fortran-font-lock-keywords-1
-        (list
-         ;; Program, subroutine and function declarations, plus calls.
-         (list (concat "\\<\\(block[ \t]*data\\|call\\|entry\\|function\\|"
-                       "program\\|subroutine\\)\\>[ \t]*\\(\\sw+\\)?")
-               '(1 font-lock-keyword-face)
-               '(2 font-lock-function-name-face nil t))))
-  (setq fortran-font-lock-keywords-2
-        (append fortran-font-lock-keywords-1
-                (list
-                 ;; Fontify all type specifiers (must be first; see below).
-                 (cons (concat "\\<\\(" fortran-type-types "\\)\\>")
-                       'font-lock-type-face)
-                 ;; Fontify all builtin keywords (except logical, do
-                 ;; and goto; see below).
-                 (concat "\\<\\(" fortran-keywords "\\)\\>")
-                 ;; Fontify all builtin operators.
-                 (concat "\\.\\(" fortran-logicals "\\)\\.")
-                 ;; Fontify do/goto keywords and targets, and goto tags.
-                 (list "\\<\\(do\\|go *to\\)\\>[ \t]*\\([0-9]+\\)?"
-                       '(1 font-lock-keyword-face)
-                       '(2 font-lock-constant-face nil t))
-                 (cons "^ *\\([0-9]+\\)" 'font-lock-constant-face))))
-  (setq fortran-font-lock-keywords-3
-        (append
-         ;; The list `fortran-font-lock-keywords-1'.
-         fortran-font-lock-keywords-1
-         ;; Fontify all type specifiers plus their declared items.
-         (list
-          (list (concat "\\<\\(" fortran-type-types "\\)\\>[ \t(/]*\\(*\\)?")
-                ;; Fontify the type specifier.
-                '(1 font-lock-type-face)
-                ;; Fontify each declaration item (or just the /.../ block name).
-                `(font-lock-match-c-style-declaration-item-and-skip-to-next
-                  ;; Start after any *(...) expression.
-                  (condition-case nil
-                     (and (and (match-beginning ,(+ 2 (regexp-opt-depth
-                                                       fortran-type-types)))
-                               (forward-sexp))
-                          (forward-sexp))
-                   (error nil))
-                  ;; No need to clean up.
-                  nil
-                  ;; Fontify as a variable name, functions are
-                  ;; fontified elsewhere.
-                  (1 font-lock-variable-name-face nil t))))
-         ;; Things extra to `fortran-font-lock-keywords-3'
-         ;; (must be done first).
-         (list
-          ;; Fontify goto-like `err=label'/`end=label' in read/write
-          ;; statements.
-          '(", *\\(e\\(nd\\|rr\\)\\)\\> *\\(= *\\([0-9]+\\)\\)?"
-            (1 font-lock-keyword-face) (4 font-lock-constant-face nil t))
-          ;; Highlight standard continuation character and in a
-          ;; TAB-formatted line.
-          '("^     \\([^ 0]\\)" 1 font-lock-string-face)
-          '("^\t\\([1-9]\\)" 1 font-lock-string-face))
-        (list 
-         ;; cpp stuff (ugh)
-         '("^# *[a-z]+" . font-lock-keyword-face))
-         ;; The list `fortran-font-lock-keywords-2' less that for types
-         ;; (see above).
-         (cdr (nthcdr (length fortran-font-lock-keywords-1)
-                      fortran-font-lock-keywords-2)))))
-
 (defvar fortran-font-lock-keywords fortran-font-lock-keywords-1
   "Default expressions to highlight in Fortran mode.")
-\f
+
 (defvar fortran-imenu-generic-expression
   ;; These patterns could be confused by sequence nos. in cols 72+ and
   ;; don't allow continuations everywhere.
@@ -392,23 +431,116 @@ These get fixed-format comments fontified.")
      ;; Variable to index:
      "\\(\\sw+\\)")
     3)
-   ;; Un-named block data
-   (list nil "^\\s-+\\(block\\s-*data\\)\\s-*$" 1))
-  "Imenu generic expression for `imenu-default-create-index-function'.")
+   ;; Un-named block data.
+   '(nil "^\\s-+\\(block\\s-*data\\)\\s-*$" 1))
+  "Value for `imenu-generic-expression' in Fortran mode.")
+
+\f
+;; Hideshow support.
+(defconst fortran-blocks-re
+  (concat "block[ \t]*data\\|select[ \t]*case\\|"
+          (regexp-opt '("do" "if" "interface" "function" "map" "program"
+                        "structure" "subroutine" "union" "where")))
+  "Regexp potentially indicating the start or end of a Fortran \"block\".
+Omits naked END statements, and DO-loops closed by anything other
+than ENDDO.")
+
+(defconst fortran-end-block-re
+  ;; Do-loops terminated by things other than ENDDO cannot be handled
+  ;; with a regexp. This omission does not seem to matter to hideshow...
+  (concat "^[ \t0-9]*\\<end[ \t]*\\("
+          fortran-blocks-re
+          ;; Naked END statement.
+          "\\|!\\|$\\)")
+  "Regexp matching the end of a Fortran \"block\", from the line start.
+Note that only ENDDO is handled for the end of a DO-loop.  Used
+in the Fortran entry in `hs-special-modes-alist'.")
+
+(defconst fortran-start-block-re
+  (concat
+   "^[ \t0-9]*\\("                      ; statement number
+   ;; Structure label for DO, IF, SELECT, WHERE.
+   "\\(\\(\\sw+[ \t]*:[ \t]*\\)?"
+   ;; IF blocks are a nuisance:
+   ;; IF ( ... ) foo   is not a block, but a single statement.
+   ;; IF ( ... ) THEN  can be split over multiple lines.
+   ;; [So can, eg, a DO WHILE (... ), but that is less common, I hope.]
+   ;; The regexp below allows for it to be split over at most 2 lines.
+   ;; That leads to the problem of not matching two consecutive IF
+   ;; statements as one, eg:
+   ;; IF ( ... ) foo
+   ;; IF ( ... ) THEN
+   ;; It simply is not possible to do this in a 100% correct fashion
+   ;; using a regexp - see the functions fortran-end-if,
+   ;; fortran-beginning-if for the hoops we have to go through.
+   ;; An alternative is to match on THEN at a line end, eg:
+   ;;   ".*)[ \t]*then[ \t]*\\($\\|!\\)"
+   ;; This would also match ELSE branches, though. This does not seem
+   ;; right to me, because then one has neighbouring blocks that are
+   ;; not nested in each other.
+   "\\(if[ \t]*(\\(.*\\|"
+   ".*\n\\([^if]*\\([^i].\\|.[^f]\\|.\\>\\)\\)\\)\\<then\\|"
+   "do\\|select[ \t]*case\\|where\\)\\)\\|"
+   (regexp-opt '("interface" "function" "map" "program"
+                 "structure" "subroutine" "union"))
+   "\\|block[ \t]*data\\)[ \t]*")
+  "Regexp matching the start of a Fortran \"block\", from the line start.
+A simple regexp cannot do this in fully correct fashion, so this
+tries to strike a compromise between complexity and flexibility.
+Used in the Fortran entry in `hs-special-modes-alist'.")
+
+(add-to-list 'hs-special-modes-alist
+            `(fortran-mode ,fortran-start-block-re ,fortran-end-block-re
+                            "^[cC*!]" fortran-end-of-block nil))
+
+\f
+(defvar fortran-mode-syntax-table
+  (let ((table (make-syntax-table)))
+    ;; We might like `;' to be punctuation (g77 multi-statement
+    ;; lines), but that screws abbrevs.
+    (modify-syntax-entry ?\; "w"  table)
+    (modify-syntax-entry ?\r " "  table)
+    (modify-syntax-entry ?+  "."  table)
+    (modify-syntax-entry ?-  "."  table)
+    (modify-syntax-entry ?=  "."  table)
+    (modify-syntax-entry ?*  "."  table)
+    (modify-syntax-entry ?/  "."  table)
+    (modify-syntax-entry ?\' "\"" table)
+    (modify-syntax-entry ?\" "\"" table)
+    ;; Consistent with GNU Fortran's default -- see the manual.
+    ;; The F77 standard imposes no rule on this issue.
+    (modify-syntax-entry ?\\ "\\" table)
+    ;; This might be better as punctuation, as for C, but this way you
+    ;; can treat floating-point numbers as symbols.
+    (modify-syntax-entry ?.  "_"  table) ; e.g. `a.ne.b'
+    (modify-syntax-entry ?_  "_"  table)
+    (modify-syntax-entry ?$  "_"  table) ; esp. VMSisms
+    (modify-syntax-entry ?\! "<"  table)
+    (modify-syntax-entry ?\n ">"  table)
+    table)
+  "Syntax table used in Fortran mode.")
+
+(defvar fortran-gud-syntax-table
+  (let ((st (make-syntax-table fortran-mode-syntax-table)))
+    (modify-syntax-entry ?\n "." st)
+    st)
+  "Syntax table used to parse Fortran expressions for printing in GUD.")
 
 (defvar fortran-mode-map
   (let ((map (make-sparse-keymap)))
-    (define-key map ";" 'fortran-abbrev-start)
-    (define-key map "\C-c;" 'fortran-comment-region)
-    (define-key map "\M-;" 'fortran-indent-comment)
-    (define-key map "\M-\n" 'fortran-split-line)
-    (define-key map "\M-\C-q" 'fortran-indent-subprogram)
+    (define-key map ";"        'fortran-abbrev-start)
+    (define-key map "\C-c;"    'fortran-comment-region)
+    (define-key map "\M-;"     'fortran-indent-comment)
+    (define-key map "\M-\n"    'fortran-split-line)
+    (define-key map "\M-\C-n"  'fortran-end-of-block)
+    (define-key map "\M-\C-p"  'fortran-beginning-of-block)
+    (define-key map "\M-\C-q"  'fortran-indent-subprogram)
     (define-key map "\C-c\C-w" 'fortran-window-create-momentarily)
     (define-key map "\C-c\C-r" 'fortran-column-ruler)
     (define-key map "\C-c\C-p" 'fortran-previous-statement)
     (define-key map "\C-c\C-n" 'fortran-next-statement)
     (define-key map "\C-c\C-d" 'fortran-join-line) ; like f90
-    (define-key map "\M-^" 'fortran-join-line) ; subvert delete-indentation
+    (define-key map "\M-^"     'fortran-join-line) ; subvert delete-indentation
     (define-key map "0" 'fortran-electric-line-number)
     (define-key map "1" 'fortran-electric-line-number)
     (define-key map "2" 'fortran-electric-line-number)
@@ -420,252 +552,248 @@ These get fixed-format comments fontified.")
     (define-key map "8" 'fortran-electric-line-number)
     (define-key map "9" 'fortran-electric-line-number)
 
-    ;; Menu
-    (easy-menu-define
-     fortran-mode-menu map ""
-     `("Fortran"
-       ["Manual" (info "(emacs)Fortran")]
-       ("Customization"
-       ,(custom-menu-create 'fortran)
-       ["Set" Custom-set t]
-       ["Save" Custom-save t]
-       ["Reset to Current" Custom-reset-current t]
-       ["Reset to Saved" Custom-reset-saved t]
-       ["Reset to Standard Settings" Custom-reset-standard t])
-       "----"
-       ["Toggle Auto-fill" auto-fill-mode :style toggle
-       :selected auto-fill-function]
-       ["Toggle abbrev-mode" abbrev-mode :style toggle :selected abbrev-mode]
-       "----"
-       ["Comment-out Region" fortran-comment-region mark-active]
-       ["Uncomment-out region"
-       (fortran-comment-region (region-beginning) (region-end) 1)
-       mark-active]
-       ["Indent Region" indent-region mark-active]
-       ["Indent Subprogram" fortran-indent-subprogram t]
-       "----"
-       ["Beginning of Subprogram" fortran-beginning-of-subprogram t]
-       ["End of Subprogram" fortran-end-of-subprogram t]
-       ("Mark"
-       ["Subprogram" mark-defun t]
-       ["IF Block" fortran-mark-if t]
-       ["DO Block" fortran-mark-do t])
-       ["Narrow to Subprogram" narrow-to-defun t]
-       ["Widen" widen t]
-       "----"
-       ["Temporary column ruler" fortran-column-ruler t]
-       ["72-column window" fortran-window-create t]
-       ["Full Width Window"
-       (enlarge-window-horizontally (- (frame-width) (window-width)))
-       (< (window-width) (frame-width))]
-       ["Momentary 72-column window" fortran-window-create-momentarily t]
-       "----"
-       ["Break Line at Point" fortran-split-line t]
-       ["Join Line" fortran-join-line t]
-       ["Fill Statement/Comment" fill-paragraph  t]
-       "----"
-       ["Add imenu menu"
-       imenu-add-menubar-index (not (and (boundp 'imenu--index-alist)
-                                         imenu--index-alist))]))
+    (easy-menu-define fortran-menu map "Menu for Fortran mode."
+      `("Fortran"
+        ["Manual" (info "(emacs)Fortran")]
+        ("Customization"
+         ,(custom-menu-create 'fortran)
+         ["Set"  Custom-set t]
+         ["Save" Custom-save t]
+         ["Reset to Current" Custom-reset-current t]
+         ["Reset to Saved"   Custom-reset-saved t]
+         ["Reset to Standard Settings" Custom-reset-standard t]
+         )
+        "--"
+        ["Comment Region" fortran-comment-region mark-active]
+        ["Uncomment Region"
+         (fortran-comment-region (region-beginning) (region-end) 1)
+         mark-active]
+        ["Indent Region"     indent-region mark-active]
+        ["Indent Subprogram" fortran-indent-subprogram t]
+        "--"
+        ["Beginning of Subprogram" fortran-beginning-of-subprogram t]
+        ["End of Subprogram"       fortran-end-of-subprogram       t]
+        ("Mark"
+         ["Subprogram" mark-defun      t]
+         ["IF Block"   fortran-mark-if t]
+         ["DO Block"   fortran-mark-do t]
+         )
+        ["Narrow to Subprogram" narrow-to-defun t]
+        ["Widen" widen t]
+        "--"
+        ["Temporary column ruler" fortran-column-ruler  t]
+        ["72-column window"       fortran-window-create t]
+        ["Full Width Window"
+         (enlarge-window-horizontally (- (frame-width) (window-width)))
+         (< (window-width) (frame-width))]
+        ["Momentary 72-column window" fortran-window-create-momentarily t]
+        "--"
+        ["Break Line at Point"    fortran-split-line t]
+        ["Join Line"              fortran-join-line  t]
+        ["Fill Statement/Comment" fill-paragraph     t]
+        "--"
+        ["Toggle auto-fill"   auto-fill-mode :selected auto-fill-function
+         :style toggle]
+        ["Toggle abbrev-mode" abbrev-mode    :selected abbrev-mode
+         :style toggle]
+        ["Add imenu Menu" imenu-add-menubar-index
+         :active   (not (lookup-key (current-local-map) [menu-bar index]))
+         :included (fboundp 'imenu-add-to-menubar)]))
     map)
   "Keymap used in Fortran mode.")
+
 \f
 (defvar fortran-mode-abbrev-table
-  (let ((ac abbrevs-changed))
-    (define-abbrev-table 'fortran-mode-abbrev-table ())
-    (define-abbrev fortran-mode-abbrev-table  ";au"  "automatic" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";b"   "byte" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";bd"  "block data" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ch"  "character" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";cl"  "close" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";c"   "continue" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";cm"  "common" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";cx"  "complex" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";df"  "define" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";di"  "dimension" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";do"  "double" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";dc"  "double complex" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";dp"  "double precision" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";dw"  "do while" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";e"   "else" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ed"  "enddo" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";el"  "elseif" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";en"  "endif" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";eq"  "equivalence" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ew"  "endwhere" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ex"  "external" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ey"  "entry" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";f"   "format" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";fa"  ".false." nil)
-    (define-abbrev fortran-mode-abbrev-table  ";fu"  "function" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";g"   "goto" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";im"  "implicit" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ib"  "implicit byte" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ic"  "implicit complex" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ich" "implicit character" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ii"  "implicit integer" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";il"  "implicit logical" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ir"  "implicit real" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";inc" "include" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";in"  "integer" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";intr" "intrinsic" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";l"   "logical" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";n"   "namelist" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";o"   "open" nil) ; was ;op
-    (define-abbrev fortran-mode-abbrev-table  ";pa"  "parameter" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";pr"  "program" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ps"  "pause" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";p"   "print" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";rc"  "record" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";re"  "real" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";r"   "read" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";rt"  "return" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";rw"  "rewind" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";s"   "stop" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";sa"  "save" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";st"  "structure" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";sc"  "static" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";su"  "subroutine" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";tr"  ".true." nil)
-    (define-abbrev fortran-mode-abbrev-table  ";ty"  "type" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";vo"  "volatile" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";w"   "write" nil)
-    (define-abbrev fortran-mode-abbrev-table  ";wh"  "where" nil)
-    (setq abbrevs-changed ac)
+  (let (abbrevs-changed)
+    (define-abbrev-table 'fortran-mode-abbrev-table nil)
+    ;; Use the 6th arg (SYSTEM-FLAG) of define-abbrev if possible.
+    ;; Only use `apply' to quieten the byte-compiler.
+    (mapcar
+     (function (lambda (element)
+                 (condition-case nil
+                     (apply 'define-abbrev fortran-mode-abbrev-table
+                            (append element '(nil 0 t)))
+                   (wrong-number-of-arguments
+                    (apply 'define-abbrev fortran-mode-abbrev-table
+                           (append element '(nil 0)))))))
+     '((";au"   "automatic"         )
+       (";b"    "byte"              )
+       (";bd"   "block data"        )
+       (";ch"   "character"         )
+       (";cl"   "close"             )
+       (";c"    "continue"          )
+       (";cm"   "common"            )
+       (";cx"   "complex"           )
+       (";df"   "define"            )
+       (";di"   "dimension"         )
+       (";do"   "double"            )
+       (";dc"   "double complex"    )
+       (";dp"   "double precision"  )
+       (";dw"   "do while"          )
+       (";e"    "else"              )
+       (";ed"   "enddo"             )
+       (";el"   "elseif"            )
+       (";en"   "endif"             )
+       (";eq"   "equivalence"       )
+       (";ew"   "endwhere"          )
+       (";ex"   "external"          )
+       (";ey"   "entry"             )
+       (";f"    "format"            )
+       (";fa"   ".false."           )
+       (";fu"   "function"          )
+       (";g"    "goto"              )
+       (";im"   "implicit"          )
+       (";ib"   "implicit byte"     )
+       (";ic"   "implicit complex"  )
+       (";ich"  "implicit character")
+       (";ii"   "implicit integer"  )
+       (";il"   "implicit logical"  )
+       (";ir"   "implicit real"     )
+       (";inc"  "include"           )
+       (";in"   "integer"           )
+       (";intr" "intrinsic"         )
+       (";l"    "logical"           )
+       (";n"    "namelist"          )
+       (";o"    "open"              )   ; was ;op
+       (";pa"   "parameter"         )
+       (";pr"   "program"           )
+       (";ps"   "pause"             )
+       (";p"    "print"             )
+       (";rc"   "record"            )
+       (";re"   "real"              )
+       (";r"    "read"              )
+       (";rt"   "return"            )
+       (";rw"   "rewind"            )
+       (";s"    "stop"              )
+       (";sa"   "save"              )
+       (";st"   "structure"         )
+       (";sc"   "static"            )
+       (";su"   "subroutine"        )
+       (";tr"   ".true."            )
+       (";ty"   "type"              )
+       (";vo"   "volatile"          )
+       (";w"    "write"             )
+       (";wh"   "where"             )))
     fortran-mode-abbrev-table))
-\f
-(eval-when-compile                     ; silence compiler
-  (defvar imenu-case-fold-search)
-  (defvar imenu-syntax-alist))
 
-(defcustom fortran-mode-hook nil
-  "Hook run by Fortran mode."
-  :type 'hook
-  :group 'fortran)
+\f
 
 ;;;###autoload
 (defun fortran-mode ()
-  "Major mode for editing Fortran code.
+  "Major mode for editing Fortran code in fixed format.
+For free format code, use `f90-mode'.
+
 \\[fortran-indent-line] indents the current Fortran line correctly.
-DO statements must not share a common CONTINUE.
+Note that DO statements must not share a common CONTINUE.
 
-Type ;? or ;\\[help-command] to display a list of built-in abbrevs for
-Fortran keywords.
+Type ;? or ;\\[help-command] to display a list of built-in abbrevs for\
+ Fortran keywords.
 
 Key definitions:
 \\{fortran-mode-map}
 
 Variables controlling indentation style and extra features:
 
- `comment-start'
-    If you want to use comments starting with `!',
-    set this to the string \"!\".
- `fortran-do-indent'
-    Extra indentation within do blocks.  (default 3)
- `fortran-if-indent'
-    Extra indentation within if blocks.  (default 3)
- `fortran-structure-indent'
-    Extra indentation within structure, union, map and interface blocks.
-    (default 3)
- `fortran-continuation-indent'
-    Extra indentation applied to continuation statements.  (default 5)
- `fortran-comment-line-extra-indent'
-    Amount of extra indentation for text within full-line comments.  (default 0)
- `fortran-comment-indent-style'
-    nil    means don't change indentation of text in full-line comments,
-    fixed  means indent that text at `fortran-comment-line-extra-indent' beyond
-           the value of `fortran-minimum-statement-indent-fixed' (for fixed
-           format continuation style) or `fortran-minimum-statement-indent-tab'
-           (for TAB format continuation style).
-    relative  means indent at `fortran-comment-line-extra-indent' beyond the
+`fortran-comment-line-start'
+  To use comments starting with `!', set this to the string \"!\".
+`fortran-do-indent'
+  Extra indentation within DO blocks (default 3).
+`fortran-if-indent'
+  Extra indentation within IF blocks (default 3).
+`fortran-structure-indent'
+  Extra indentation within STRUCTURE, UNION, MAP and INTERFACE blocks.
+  (default 3)
+`fortran-continuation-indent'
+  Extra indentation applied to continuation statements (default 5).
+`fortran-comment-line-extra-indent'
+  Amount of extra indentation for text in full-line comments (default 0).
+`fortran-comment-indent-style'
+  How to indent the text in full-line comments. Allowed values are:
+  nil       don't change the indentation
+  fixed     indent to `fortran-comment-line-extra-indent' beyond the
+              value of either
+                `fortran-minimum-statement-indent-fixed' (fixed format) or
+                `fortran-minimum-statement-indent-tab' (TAB format),
+              depending on the continuation format in use.
+  relative  indent to `fortran-comment-line-extra-indent' beyond the
              indentation for a line of code.
-    (default 'fixed)
- `fortran-comment-indent-char'
-    Single-character string to be inserted instead of space for
-    full-line comment indentation.  (default \" \")
- `fortran-minimum-statement-indent-fixed'
-    Minimum indentation for Fortran statements in fixed format mode.  (def.6)
- `fortran-minimum-statement-indent-tab'
-    Minimum indentation for Fortran statements in TAB format mode.  (default 9)
- `fortran-line-number-indent'
-    Maximum indentation for line numbers.  A line number will get
-    less than this much indentation if necessary to avoid reaching
-    column 5.  (default 1)
- `fortran-check-all-num-for-matching-do'
-    Non-nil causes all numbered lines to be treated as possible \"continue\"
-    statements.  (default nil)
- `fortran-blink-matching-if'
-    Non-nil causes \\[fortran-indent-line] on an ENDIF statement to blink on
-    matching IF.  Also, from an ENDDO statement, blink on matching DO [WHILE]
-    statement.  (default nil)
- `fortran-continuation-string'
-    Single-character string to be inserted in column 5 of a continuation
-    line.  (default \"$\")
- `fortran-comment-region'
-    String inserted by \\[fortran-comment-region] at start of each line in
-    region.  (default \"c$$$\")
- `fortran-electric-line-number'
-    Non-nil causes line number digits to be moved to the correct column
-    as typed.  (default t)
- `fortran-break-before-delimiters'
-    Non-nil causes lines to be broken before delimiters.
-    (default t)
+  (default 'fixed)
+`fortran-comment-indent-char'
+  Single-character string to be inserted instead of space for
+  full-line comment indentation (default \" \").
+`fortran-minimum-statement-indent-fixed'
+  Minimum indentation for statements in fixed format mode (default 6).
+`fortran-minimum-statement-indent-tab'
+  Minimum indentation for statements in TAB format mode (default 9).
+`fortran-line-number-indent'
+  Maximum indentation for line numbers (default 1).  A line number will
+  get less than this much indentation if necessary to avoid reaching
+  column 5.
+`fortran-check-all-num-for-matching-do'
+  Non-nil causes all numbered lines to be treated as possible \"continue\"
+  statements (default nil).
+`fortran-blink-matching-if'
+  Non-nil causes \\[fortran-indent-line] on an ENDIF (or ENDDO) statement
+  to blink on the matching IF (or DO [WHILE]).  (default nil)
+`fortran-continuation-string'
+  Single-character string to be inserted in column 5 of a continuation
+  line (default \"$\").
+`fortran-comment-region'
+  String inserted by \\[fortran-comment-region] at start of each line in
+  the region (default \"c$$$\").
+`fortran-electric-line-number'
+  Non-nil causes line number digits to be moved to the correct column
+  as typed (default t).
+`fortran-break-before-delimiters'
+  Non-nil causes lines to be broken before delimiters (default t).
 
 Turning on Fortran mode calls the value of the variable `fortran-mode-hook'
 with no args, if that value is non-nil."
   (interactive)
   (kill-all-local-variables)
-  (setq local-abbrev-table fortran-mode-abbrev-table)
+  (setq major-mode 'fortran-mode
+        mode-name "Fortran"
+        local-abbrev-table fortran-mode-abbrev-table)
   (set-syntax-table fortran-mode-syntax-table)
-  ;; Font Lock mode support.
-  (make-local-variable 'font-lock-defaults)
-  (setq font-lock-defaults '((fortran-font-lock-keywords
-                             fortran-font-lock-keywords-1
-                             fortran-font-lock-keywords-2
-                             fortran-font-lock-keywords-3)
-                            nil t ((?/ . "$/") ("_$" . "w"))
-                            fortran-beginning-of-subprogram))
-  (set (make-local-variable 'font-lock-syntactic-keywords)
-       fortran-font-lock-syntactic-keywords)
-  (make-local-variable 'fortran-break-before-delimiters)
-  (setq fortran-break-before-delimiters t)
-  (make-local-variable 'indent-line-function)
-  (setq indent-line-function 'fortran-indent-line)
-  (make-local-variable 'comment-indent-function)
-  (setq comment-indent-function 'fortran-comment-indent)
-  (make-local-variable 'comment-start-skip)
-  (setq comment-start-skip "![ \t]*")
-  (make-local-variable 'comment-start)
-  (setq comment-start fortran-comment-line-start)
-  (make-local-variable 'require-final-newline)
-  (setq require-final-newline t)
-  (make-local-variable 'abbrev-all-caps)
-  (setq abbrev-all-caps t)
-  (make-local-variable 'indent-tabs-mode)
-  (setq indent-tabs-mode nil)
-;;;(setq abbrev-mode t) ; ?? (abbrev-mode 1) instead??
-  (set (make-local-variable 'fill-column) 72)
   (use-local-map fortran-mode-map)
-  (setq mode-name "Fortran")
-  (setq major-mode 'fortran-mode)
-  (make-local-variable 'fortran-comment-line-extra-indent)
-  (make-local-variable 'fortran-minimum-statement-indent-fixed)
-  (make-local-variable 'fortran-minimum-statement-indent-tab)
-  (make-local-variable 'fortran-column-ruler-fixed)
-  (make-local-variable 'fortran-column-ruler-tab)
-  (setq fortran-tab-mode-string " TAB-format")
-  (setq indent-tabs-mode (fortran-analyze-file-format))
-  (setq imenu-case-fold-search t)
-  (setq imenu-generic-expression fortran-imenu-generic-expression)
-  (setq imenu-syntax-alist '(("_$" . "w")))
-  (set (make-local-variable 'fill-paragraph-function) 'fortran-fill-paragraph)
-  (set (make-local-variable 'normal-auto-fill-function) 'fortran-auto-fill)
   (set (make-local-variable 'indent-line-function) 'fortran-indent-line)
   (set (make-local-variable 'indent-region-function)
        (lambda (start end)
          (let (fortran-blink-matching-if ; avoid blinking delay
                indent-region-function)
            (indent-region start end nil))))
+  (set (make-local-variable 'require-final-newline) mode-require-final-newline)
+  ;; The syntax tables don't understand the column-0 comment-markers.
+  (set (make-local-variable 'comment-use-syntax) nil)
+  (set (make-local-variable 'comment-padding) "$$$")
+  (set (make-local-variable 'comment-start) fortran-comment-line-start)
+  (set (make-local-variable 'comment-start-skip)
+       ;; We can't reuse `fortran-comment-line-start-skip' directly because
+       ;; it contains backrefs whereas we need submatch-1 to end at the
+       ;; beginning of the comment delimiter.
+       ;; (concat "\\(\\)\\(![ \t]*\\|" fortran-comment-line-start-skip "\\)")
+       "\\(\\)\\(?:^[CcDd*]\\|!\\)\\(?:\\([^ \t\n]\\)\\2+\\)?[ \t]*")
+  (set (make-local-variable 'comment-indent-function) 'fortran-comment-indent)
+  (set (make-local-variable 'abbrev-all-caps) t)
+  (set (make-local-variable 'normal-auto-fill-function) 'fortran-auto-fill)
+  (set (make-local-variable 'indent-tabs-mode) (fortran-analyze-file-format))
+  (setq mode-line-process '(indent-tabs-mode fortran-tab-mode-string))
+  (set (make-local-variable 'fill-column) 72)
+  (set (make-local-variable 'fill-paragraph-function) 'fortran-fill-paragraph)
+  (set (make-local-variable 'font-lock-defaults)
+       '((fortran-font-lock-keywords
+          fortran-font-lock-keywords-1
+          fortran-font-lock-keywords-2
+          fortran-font-lock-keywords-3
+          fortran-font-lock-keywords-4)
+         nil t ((?/ . "$/") ("_$" . "w"))
+         fortran-beginning-of-subprogram))
+  (set (make-local-variable 'font-lock-syntactic-keywords)
+       fortran-font-lock-syntactic-keywords)
+  (set (make-local-variable 'imenu-case-fold-search) t)
+  (set (make-local-variable 'imenu-generic-expression)
+       fortran-imenu-generic-expression)
+  (set (make-local-variable 'imenu-syntax-alist) '(("_$" . "w")))
   (set (make-local-variable 'beginning-of-defun-function)
        #'fortran-beginning-of-subprogram)
   (set (make-local-variable 'end-of-defun-function)
@@ -673,39 +801,46 @@ with no args, if that value is non-nil."
   (set (make-local-variable 'add-log-current-defun-function)
        #'fortran-current-defun)
   (set (make-local-variable 'dabbrev-case-fold-search) 'case-fold-search)
-  (run-hooks 'fortran-mode-hook))
+  (set (make-local-variable 'gud-find-expr-function) 'fortran-gud-find-expr)
+  (run-mode-hooks 'fortran-mode-hook))
+
 \f
+(defun fortran-gud-find-expr ()
+  ;; Consider \n as punctuation (end of expression).
+  (with-syntax-table fortran-gud-syntax-table
+    (gud-find-c-expr)))
+
 (defsubst fortran-comment-indent ()
-  (save-excursion
-    (skip-chars-backward " \t")
-    (max (+ 1 (current-column))
-        comment-column)))
+  "Return the indentation appropriate for the current comment line.
+This is 0 for a line matching `fortran-comment-line-start-skip', else
+the value of `comment-column' (leaving at least one space after code)."
+  (if (looking-at fortran-comment-line-start-skip) 0
+    (save-excursion
+      (skip-chars-backward " \t")
+      (max (1+ (current-column)) comment-column))))
 
 (defun fortran-indent-comment ()
   "Align or create comment on current line.
 Existing comments of all types are recognized and aligned.
-If the line has no comment, a side-by-side comment is inserted and aligned
-if the value of  `comment-start'  is not nil.
+If the line has no comment, a side-by-side comment is inserted and aligned,
+if the value of `comment-start' is not nil and allows such comments.
 Otherwise, a separate-line comment is inserted, on this line
 or on a new line inserted before this line if this line is not blank."
-  (interactive)
+  (interactive "*")
   (beginning-of-line)
   ;; Recognize existing comments of either kind.
-  (cond ((looking-at fortran-comment-line-start-skip)
-        (fortran-indent-line))
-       ((fortran-find-comment-start-skip) ; catches any inline comment and
-                                       ; leaves point after comment-start-skip
-        (if comment-start-skip
-            (progn (goto-char (match-beginning 0))
-                   (if (not (= (current-column)
-                               (fortran-comment-indent)))
-                       (progn (delete-horizontal-space)
-                              (indent-to (fortran-comment-indent)))))
-          (end-of-line)))        ; otherwise goto end of line or sth else?
+  (cond ((fortran-find-comment-start-skip 'all)
+        (goto-char (match-beginning 0))
+        (if (bolp)
+            (fortran-indent-line)
+          (unless (= (current-column) (fortran-comment-indent))
+             (delete-horizontal-space)
+             (indent-to (fortran-comment-indent)))))
        ;; No existing comment.
        ;; If side-by-side comments are defined, insert one,
        ;; unless line is now blank.
-       ((and comment-start (not (looking-at "^[ \t]*$")))
+       ((and comment-start (not (looking-at "[ \t]*$"))
+             (string-match comment-start-skip (concat " " comment-start)))
         (end-of-line)
         (delete-horizontal-space)
         (indent-to (fortran-comment-indent))
@@ -724,41 +859,48 @@ or on a new line inserted before this line if this line is not blank."
                      (- (fortran-calculate-indent) (current-column))))))
 
 (defun fortran-comment-region (beg-region end-region arg)
-  "Comments every line in the region.
-Puts `fortran-comment-region' at the beginning of every line in the region.
-BEG-REGION and END-REGION are args which specify the region boundaries.
+  "Comment every line in the region.
+Inserts the string variable `fortran-comment-region' at the beginning of
+every line in the region.
+BEG-REGION and END-REGION specify the region boundaries.
 With non-nil ARG, uncomments the region."
   (interactive "*r\nP")
   (let ((end-region-mark (copy-marker end-region))
        (save-point (point-marker)))
     (goto-char beg-region)
     (beginning-of-line)
-    (if (not arg)                      ;comment the region
-       (progn (insert fortran-comment-region)
-              (while (and  (= (forward-line 1) 0)
-                           (< (point) end-region-mark))
-                (insert fortran-comment-region)))
-      (let ((com (regexp-quote fortran-comment-region))) ;uncomment the region
-       (if (looking-at com)
-           (delete-region (point) (match-end 0)))
-       (while (and  (= (forward-line 1) 0)
-                    (< (point) end-region-mark))
-         (if (looking-at com)
-             (delete-region (point) (match-end 0))))))
+    (if arg
+        (let ((com (regexp-quote fortran-comment-region))) ; uncomment
+          (if (looking-at com)
+              (delete-region (point) (match-end 0)))
+          (while (and (zerop (forward-line 1))
+                      (< (point) end-region-mark))
+            (if (looking-at com)
+                (delete-region (point) (match-end 0)))))
+      (insert fortran-comment-region)   ; comment
+      (while (and (zerop (forward-line 1))
+                  (< (point) end-region-mark))
+        (insert fortran-comment-region)))
     (goto-char save-point)
     (set-marker end-region-mark nil)
     (set-marker save-point nil)))
+
 \f
 (defun fortran-abbrev-start ()
   "Typing ;\\[help-command] or ;? lists all the Fortran abbrevs.
 Any other key combination is executed normally."
-  (interactive)
-  (let (c)
-    (insert last-command-char)
-    (if (or (eq (setq c (read-event)) ??)    ;insert char if not equal to `?'
-           (eq c help-char))
+  (interactive "*")
+  (insert last-command-char)
+  (let (char event)
+    (if (fboundp 'next-command-event) ; XEmacs
+        (setq event (next-command-event)
+              char (event-to-character event))
+      (setq event (read-event)
+            char event))
+    ;; Insert char if not equal to `?', or if abbrev-mode is off.
+    (if (and abbrev-mode (or (eq char ??) (eq char help-char)))
        (fortran-abbrev-help)
-      (setq unread-command-events (list c)))))
+      (setq unread-command-events (list event)))))
 
 (defun fortran-abbrev-help ()
   "List the currently defined abbrevs in Fortran mode."
@@ -768,6 +910,7 @@ Any other key combination is executed normally."
   (message "Listing abbrev table...done"))
 
 (defun fortran-prepare-abbrev-list-buffer ()
+  "Create a buffer listing the Fortran mode abbreviations."
   (save-excursion
     (set-buffer (get-buffer-create "*Abbrevs*"))
     (erase-buffer)
@@ -779,9 +922,9 @@ Any other key combination is executed normally."
 
 (defun fortran-column-ruler ()
   "Insert a column ruler momentarily above current line, till next keystroke.
-The ruler is defined by the value of `fortran-column-ruler-fixed' when in fixed
-format mode, and `fortran-column-ruler-tab' when in TAB format mode.
-The key typed is executed unless it is SPC."
+The ruler is defined by the value of `fortran-column-ruler-fixed' in fixed
+format mode, and `fortran-column-ruler-tab' in TAB format mode.
+The next key typed is executed unless it is SPC."
   (interactive)
   (momentary-string-display
    (if indent-tabs-mode
@@ -799,22 +942,18 @@ The key typed is executed unless it is SPC."
   "Make the window 72 columns wide.
 See also `fortran-window-create-momentarily'."
   (interactive)
-  (condition-case error
-      (progn
-       (let ((window-min-width 2))
-         (if (< (window-width) (frame-width))
-             (enlarge-window-horizontally (- (frame-width)
-                                             (window-width) 1)))
-         (let* ((window-edges (window-edges))
-                (scroll-bar-width (- (nth 2 window-edges)
-                                     (car window-edges)
-                                     (window-width))))
-           (split-window-horizontally (+ 72 scroll-bar-width)))
-         (other-window 1)
-         (switch-to-buffer " fortran-window-extra" t)
-         (select-window (previous-window))))
-    (error (message "No room for Fortran window")
-          'error)))
+  (let ((window-min-width 2))
+    (if (< (window-width) (frame-width))
+       (enlarge-window-horizontally (- (frame-width)
+                                       (window-width) 1)))
+    (let* ((window-edges (window-edges))
+          (scroll-bar-width (- (nth 2 window-edges)
+                               (car window-edges)
+                               (window-width))))
+      (split-window-horizontally (+ 72 scroll-bar-width)))
+    (other-window 1)
+    (switch-to-buffer " fortran-window-extra" t)
+    (select-window (previous-window))))
 
 (defun fortran-window-create-momentarily (&optional arg)
   "Momentarily make the window 72 columns wide.
@@ -824,31 +963,38 @@ See also `fortran-window-create'."
   (if (or (not arg)
          (= arg 1))
       (save-window-excursion
-       (if (not (equal (fortran-window-create) 'error))
-           (progn (message "Type SPC to continue editing.")
-                  (let ((char (read-event)))
-                    (or (equal char (string-to-char " "))
-                        (setq unread-command-events (list char)))))))
+       (progn
+         (condition-case nil
+             (fortran-window-create)
+           (error (error "No room for Fortran window")))
+         (message "Type SPC to continue editing.")
+         (let ((char (read-event)))
+           (or (equal char (string-to-char " "))
+               (setq unread-command-events (list char))))))
     (fortran-window-create)))
 
 (defun fortran-split-line ()
   "Break line at point and insert continuation marker and alignment."
-  (interactive)
+  (interactive "*")
   (delete-horizontal-space)
   (if (save-excursion
-       (beginning-of-line)
-       (looking-at fortran-comment-line-start-skip))
-      (insert ?\n fortran-comment-line-start ? )
+       (let ((pos (point)))
+         (beginning-of-line)
+         (and (fortran-find-comment-start-skip 'all)
+              (< (match-beginning 0) pos))))
+      (insert ?\n (match-string 0))
     (if indent-tabs-mode
        (insert ?\n ?\t (fortran-numerical-continuation-char))
-      (insert "\n " fortran-continuation-string))) ; Space after \n important
-  (fortran-indent-line))               ; when the cont string is C, c or *.
+      (insert "\n " fortran-continuation-string))) ; space after \n important
+  (fortran-indent-line))               ; when cont string is C, c or *
 
 (defun fortran-remove-continuation ()
-  (if (looking-at "\\(     [^ 0\n]\\|\t[1-9]\\|&\\)")
-      (progn (replace-match "")
-            (delete-indentation)
-            t)))
+  "Delete any Fortran continuation characters at point.
+Returns t if anything actually deleted."
+  (when (looking-at "\\( \\{5\\}[^ 0\n]\\|\t[1-9]\\|&\\)")
+    (replace-match "")
+    (delete-indentation)
+    t))
 
 (defun fortran-join-line (arg)
   "Join current line to the previous one and re-indent.
@@ -869,19 +1015,19 @@ Continuation lines are correctly handled."
 
 (defun fortran-numerical-continuation-char ()
   "Return a digit for tab-digit style of continuation lines.
-If, previous line is a tab-digit continuation line, returns that digit
-plus one.  Otherwise return 1.  Zero not allowed."
+If previous line is a tab-digit continuation line, return that digit
+plus one, otherwise return 1.  Zero not allowed."
   (save-excursion
     (forward-line -1)
     (if (looking-at "\t[1-9]")
-       (+ ?1 (% (- (char-after (+ (point) 1)) ?0) 9))
+       (+ ?1 (% (- (char-after (1+ (point))) ?0) 9))
       ?1)))
 
 (put 'fortran-electric-line-number 'delete-selection t)
 (defun fortran-electric-line-number (arg)
   "Self insert, but if part of a Fortran line number indent it automatically.
 Auto-indent does not happen if a numeric ARG is used."
-  (interactive "P")
+  (interactive "*P")
   (if (or arg (not fortran-electric-line-number))
       (if arg
          (self-insert-command (prefix-numeric-value arg))
@@ -889,33 +1035,27 @@ Auto-indent does not happen if a numeric ARG is used."
     (if (or (and (= 5 (current-column))
                 (save-excursion
                   (beginning-of-line)
-                  (looking-at " \\{5\\}"))) ;In col 5 with only spaces to left.
+                    ;; In col 5 with only spaces to the left.
+                  (looking-at " \\{5\\}")))
            (and (= (if indent-tabs-mode
                        fortran-minimum-statement-indent-tab
                      fortran-minimum-statement-indent-fixed) (current-column))
-                (eq ?\t (char-after (line-beginning-position))) ;In col 8
-                                       ; with a single tab to the left.
+                 ;; In col 8 with a single tab to the left.
+                (eq ?\t (char-after (line-beginning-position)))
                 (not (or (eq last-command 'fortran-indent-line)
                          (eq last-command
                              'fortran-indent-new-line))))
            (save-excursion
              (re-search-backward "[^ \t0-9]"
                                  (line-beginning-position)
-                                 t))   ;not a line number
-           (looking-at "[0-9]"))       ;within a line number
+                                 t))   ; not a line number
+           (looking-at "[0-9]"))       ; within a line number
        (self-insert-command (prefix-numeric-value arg))
       (skip-chars-backward " \t")
       (insert last-command-char)
       (fortran-indent-line))))
-\f
-(defvar fortran-end-prog-re1
-  "end\
-\\([ \t]*\\(program\\|subroutine\\|function\\|block[ \t]*data\\)\\>\
-\\([ \t]*\\(\\sw\\|\\s_\\)+\\)?\\)?")
-(defvar fortran-end-prog-re
-  (concat "^[ \t0-9]*" fortran-end-prog-re1)
-  "Regexp possibly marking subprogram end.")
 
+\f
 (defun fortran-check-end-prog-re ()
   "Check a preliminary match against `fortran-end-prog-re'."
   ;; Having got a possible match for the subprogram end, we need a
@@ -929,7 +1069,7 @@ Auto-indent does not happen if a numeric ARG is used."
 ;; Note that you can't just check backwards for `subroutine' &c in
 ;; case of un-marked main programs not at the start of the file.
 (defun fortran-beginning-of-subprogram ()
-  "Moves point to the beginning of the current Fortran subprogram."
+  "Move point to the beginning of the current Fortran subprogram."
   (interactive)
   (save-match-data
     (let ((case-fold-search t))
@@ -941,7 +1081,7 @@ Auto-indent does not happen if a numeric ARG is used."
          (forward-line)))))
 
 (defun fortran-end-of-subprogram ()
-  "Moves point to the end of the current Fortran subprogram."
+  "Move point to the end of the current Fortran subprogram."
   (interactive)
   (save-match-data
     (let ((case-fold-search t))
@@ -959,21 +1099,27 @@ Auto-indent does not happen if a numeric ARG is used."
        (forward-line)))))
 
 (defun fortran-previous-statement ()
-  "Moves point to beginning of the previous Fortran statement.
-Returns `first-statement' if that statement is the first
-non-comment Fortran statement in the file, and nil otherwise."
+  "Move point to beginning of the previous Fortran statement.
+Returns 'first-statement if that statement is the first
+non-comment Fortran statement in the file, and nil otherwise.
+Directive lines are treated as comments."
   (interactive)
   (let (not-first-statement continue-test)
     (beginning-of-line)
     (setq continue-test
          (and
           (not (looking-at fortran-comment-line-start-skip))
+           (not (looking-at fortran-directive-re))
           (or (looking-at
                (concat "[ \t]*"
                        (regexp-quote fortran-continuation-string)))
               (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]"))))
-    (while (and (setq not-first-statement (= (forward-line -1) 0))
+    (while (and (setq not-first-statement (zerop (forward-line -1)))
                (or (looking-at fortran-comment-line-start-skip)
+                    (looking-at fortran-directive-re)
+                    (looking-at
+                     (concat "[ \t]*"
+                             (regexp-quote fortran-continuation-string)))
                    (looking-at "[ \t]*$\\| \\{5\\}[^ 0\n]\\|\t[1-9]")
                    (looking-at (concat "[ \t]*" comment-start-skip)))))
     (cond ((and continue-test
@@ -985,20 +1131,101 @@ non-comment Fortran statement in the file, and nil otherwise."
           'first-statement))))
 
 (defun fortran-next-statement ()
-  "Moves point to beginning of the next Fortran statement.
-Returns `last-statement' if that statement is the last
-non-comment Fortran statement in the file, and nil otherwise."
+  "Move point to beginning of the next Fortran statement.
+Returns 'last-statement if that statement is the last
+non-comment Fortran statement in the file, and nil otherwise.
+Directive lines are treated as comments."
   (interactive)
   (let (not-last-statement)
     (beginning-of-line)
     (while (and (setq not-last-statement
-                     (and (= (forward-line 1) 0)
+                     (and (zerop (forward-line 1))
                           (not (eobp))))
                (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)))))
     (if (not not-last-statement)
        'last-statement)))
+
+(defun fortran-looking-at-if-then ()
+  "Return non-nil if at the start of a line with an IF ... THEN statement."
+  ;; cf f90-looking-at-if-then.
+  (let ((p (point))
+        (i (fortran-beginning-if)))
+    (if i
+        (save-excursion
+          (goto-char i)
+          (beginning-of-line)
+          (= (point) p)))))
+
+;; Used in hs-special-modes-alist.
+(defun fortran-end-of-block (&optional num)
+  "Move point forward to the end of the current code block.
+With optional argument NUM, go forward that many balanced blocks.
+If NUM is negative, go backward to the start of a block.  Does
+not check for consistency of block types.  Interactively, pushes
+mark before moving point."
+  (interactive "p")
+  (if (interactive-p) (push-mark (point) t))
+  (and num (< num 0) (fortran-beginning-of-block (- num)))
+  (let ((case-fold-search t)
+        (count (or num 1)))
+    (end-of-line)
+    (while (and (> count 0)
+                (re-search-forward
+                 (concat "\\(" fortran-blocks-re
+                         (if fortran-check-all-num-for-matching-do
+                             "\\|^[ \t]*[0-9]+" "")
+                         "\\|continue\\|end\\)\\>")
+                 nil 'move))
+      (beginning-of-line)
+      (if (if (looking-at (concat "^[0-9 \t]*" fortran-if-start-re))
+              (fortran-looking-at-if-then)
+            (looking-at fortran-start-block-re))
+          (setq count (1+ count))
+        (if (or (looking-at fortran-end-block-re)
+                (and (or (looking-at "^[0-9 \t]*continue")
+                         (and fortran-check-all-num-for-matching-do
+                              (looking-at "[ \t]*[0-9]+")))
+                     (fortran-check-for-matching-do)))
+            (setq count (1- count))))
+      (end-of-line))
+    (if (> count 0) (error "Missing block end"))))
+
+(defun fortran-beginning-of-block (&optional num)
+  "Move point backwards to the start of the current code block.
+With optional argument NUM, go backward that many balanced
+blocks.  If NUM is negative, go forward to the end of a block.
+Does not check for consistency of block types.  Interactively,
+pushes mark before moving point."
+  (interactive "p")
+  (if (interactive-p) (push-mark (point) t))
+  (and num (< num 0) (fortran-end-of-block (- num)))
+  (let ((case-fold-search t)
+        (count (or num 1)))
+    (beginning-of-line)
+    (while (and (> count 0)
+                (re-search-backward
+                 (concat "\\(" fortran-blocks-re
+                         (if fortran-check-all-num-for-matching-do
+                             "\\|^[ \t]*[0-9]+" "")
+                         "\\|continue\\|end\\)\\>")
+                 nil 'move))
+      (beginning-of-line)
+      (if (if (looking-at (concat "^[0-9 \t]*" fortran-if-start-re))
+              (fortran-looking-at-if-then)
+            (looking-at fortran-start-block-re))
+          (setq count (1- count))
+        (if (or (looking-at fortran-end-block-re)
+                (and (or (looking-at "^[0-9 \t]*continue")
+                         (and fortran-check-all-num-for-matching-do
+                              (looking-at "[ \t]*[0-9]+")))
+                     (fortran-check-for-matching-do)))
+            (setq count (1+ count)))))
+    ;; Includes an un-named main program block.
+    (if (> count 0) (error "Missing block start"))))
+
 \f
 (defun fortran-blink-match (regex keyword find-begin)
   "From a line matching REGEX, blink matching KEYWORD statement line.
@@ -1008,26 +1235,25 @@ Use function FIND-BEGIN to match it."
        (case-fold-search t)
        matching
        message)
-    (if (save-excursion
-         (beginning-of-line)
-         (skip-chars-forward " \t0-9")
-         (looking-at regex))
-       (progn
-          (if (not (setq matching (funcall find-begin)))
-              (setq message (concat "No matching " keyword "."))
-            (if (< matching top-of-window)
-                (save-excursion
-                  (goto-char matching)
-                  (beginning-of-line)
-                  (setq message
-                        (concat "Matches "
-                                (buffer-substring (point)
-                                                 (line-end-position)))))))
-         (if message
-             (message "%s" message)
-           (goto-char matching)
-           (sit-for 1)
-           (goto-char end-point))))))
+    (when (save-excursion
+            (beginning-of-line)
+            (skip-chars-forward " \t0-9")
+            (looking-at regex))
+      (if (not (setq matching (funcall find-begin)))
+          (setq message (concat "No matching " keyword "."))
+        (if (< matching top-of-window)
+            (save-excursion
+              (goto-char matching)
+              (beginning-of-line)
+              (setq message
+                    (concat "Matches "
+                            (buffer-substring (point)
+                                              (line-end-position)))))))
+      (if message
+          (message "%s" message)
+        (goto-char matching)
+        (sit-for blink-matching-delay)
+        (goto-char end-point)))))
 
 (defun fortran-blink-matching-if ()
   "From an ENDIF or ELSE statement, blink the matching IF statement."
@@ -1062,9 +1288,9 @@ Return point or nil."
       ;; Search for one.
       (save-excursion
        (let ((count 1))
-         (while (and (not (= count 0))
+         (while (and (not (zerop count))
                      (not (eq (fortran-next-statement) 'last-statement))
-                     ;; Keep local to subprogram
+                     ;; Keep local to subprogram.
                      (not (and (looking-at fortran-end-prog-re)
                                (fortran-check-end-prog-re))))
            (skip-chars-forward " \t0-9")
@@ -1072,36 +1298,37 @@ Return point or nil."
                   (setq count (1- count)))
                  ((looking-at
                    "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?do[ \t]+[^0-9]")
-                  (setq count (+ count 1)))))
-         (and (= count 0)
+                  (setq count (1+ count)))))
+         (and (zerop count)
               ;; All pairs accounted for.
               (point)))))))
 
 (defun fortran-beginning-do ()
   "Search backwards for first unmatched DO [WHILE].
-Return point or nil."
-  (let ((case-fold-search t))
+Return point or nil.  Ignores labelled DO loops (ie DO 10 ... 10 CONTINUE)."
+  (let ((case-fold-search t)
+        (dostart-re "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?do[ \t]+[^0-9]"))
     (if (save-excursion
          (beginning-of-line)
          (skip-chars-forward " \t0-9")
-         (looking-at "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?do[ \t]+"))
+         (looking-at dostart-re))
        ;; Sitting on one.
        (match-beginning 0)
       ;; Search for one.
       (save-excursion
        (let ((count 1))
-         (while (and (not (= count 0))
+         (while (and (not (zerop count))
                      (not (eq (fortran-previous-statement) 'first-statement))
-                     ;; Keep local to subprogram
+                     ;; Keep local to subprogram.
                      (not (and (looking-at fortran-end-prog-re)
                                (fortran-check-end-prog-re))))
            (skip-chars-forward " \t0-9")
-           (cond ((looking-at
-                   "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?do[ \t]+[^0-9]")
+           (cond ((looking-at dostart-re)
                   (setq count (1- count)))
+                  ;; Note labelled loop ends not considered.
                  ((looking-at "end[ \t]*do\\b")
                   (setq count (1+ count)))))
-         (and (= count 0)
+         (and (zerop count)
               ;; All pairs accounted for.
               (point)))))))
 
@@ -1118,8 +1345,6 @@ The marks are pushed."
           (push-mark)
           (goto-char if-point)))))
 
-(defvar fortran-if-start-re "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?if[ \t]*(")
-
 (defun fortran-end-if ()
   "Search forwards for first unmatched ENDIF.
 Return point or nil."
@@ -1133,22 +1358,22 @@ Return point or nil."
       ;; letter on line but this should not cause troubles.
       (save-excursion
        (let ((count 1))
-         (while (and (not (= count 0))
+         (while (and (not (zerop count))
                      (not (eq (fortran-next-statement) 'last-statement))
                      ;; Keep local to subprogram.
                      (not (and (looking-at fortran-end-prog-re)
                                (fortran-check-end-prog-re))))
            (skip-chars-forward " \t0-9")
            (cond ((looking-at "end[ \t]*if\\b")
-                  (setq count (- count 1)))
+                  (setq count (1- count)))
                  ((looking-at fortran-if-start-re)
                   (save-excursion
                     (if (or
                          (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t(=a-z0-9]")
-                         (let (then-test) ; Multi-line if-then.
+                         (let (then-test) ; multi-line if-then
                            (while
                                (and
-                                (= (forward-line 1) 0)
+                                (zerop (forward-line 1))
                                 ;; Search forward for then.
                                 (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")
                                 (not
@@ -1156,8 +1381,8 @@ Return point or nil."
                                        (looking-at
                                         ".*then\\b[ \t]*[^ \t(=a-z0-9]")))))
                            then-test))
-                        (setq count (+ count 1)))))))
-         (and (= count 0)
+                        (setq count (1+ count)))))))
+         (and (zerop count)
               ;; All pairs accounted for.
               (point)))))))
 
@@ -1181,7 +1406,7 @@ Return point or nil."
                 ;; Multi-line if-then.
                 (let (then-test)
                   (while
-                     (and (= (forward-line 1) 0)
+                       (and (zerop (forward-line 1))
                            ;; Search forward for then.
                            (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")
                            (not
@@ -1194,7 +1419,7 @@ Return point or nil."
       ;; Search for one.
       (save-excursion
        (let ((count 1))
-         (while (and (not (= count 0))
+         (while (and (not (zerop count))
                      (not (eq (fortran-previous-statement) 'first-statement))
                      ;; Keep local to subprogram.
                      (not (and (looking-at fortran-end-prog-re)
@@ -1204,28 +1429,29 @@ Return point or nil."
                   (save-excursion
                     (if (or
                          (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t(=a-z0-9]")
-                         (let (then-test) ; Multi-line if-then.
+                         (let (then-test) ; multi-line if-then
                            (while
                                (and
-                                (= (forward-line 1) 0)
+                                (zerop (forward-line 1))
                                 ;; Search forward for then.
                                 (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")
                                 (not
                                  (setq then-test
                                        (looking-at
                                         (concat ".*then\\b[ \t]*"
-                                                "[^ \t(=a-z[0-9]]"))))))
+                                                "[^ \t(=a-z0-9]"))))))
                            then-test))
-                        (setq count (- count 1)))))
+                        (setq count (1- count)))))
                  ((looking-at "end[ \t]*if\\b")
-                  (setq count (+ count 1)))))
-         (and (= count 0)
+                  (setq count (1+ count)))))
+         (and (zerop count)
               ;; All pairs accounted for.
               (point)))))))
+
 \f
 (defun fortran-indent-line ()
   "Indent current Fortran line based on its contents and on previous lines."
-  (interactive)
+  (interactive "*")
   (let ((cfi (fortran-calculate-indent)))
     (save-excursion
       (beginning-of-line)
@@ -1234,24 +1460,23 @@ Return point or nil."
                   (not (fortran-line-number-indented-correctly-p))))
          (fortran-indent-to-column cfi)
        (beginning-of-line)
-       (if (and (not (looking-at fortran-comment-line-start-skip))
-                (fortran-find-comment-start-skip))
+       (if (fortran-find-comment-start-skip)
            (fortran-indent-comment))))
     ;; Never leave point in left margin.
     (if (< (current-column) cfi)
        (move-to-column cfi))
-    (if (and auto-fill-function
-            (> (save-excursion (end-of-line) (current-column))
-               fill-column))
-       (save-excursion
-         (end-of-line)
-         (fortran-fill)))
-    (if fortran-blink-matching-if
-        (progn
-         (fortran-blink-matching-if)
-         (fortran-blink-matching-do)))))
+    (and auto-fill-function
+         (> (save-excursion (end-of-line) (current-column))
+            fill-column)
+         (save-excursion
+           (end-of-line)
+           (fortran-fill)))
+    (when fortran-blink-matching-if
+      (fortran-blink-matching-if)
+      (fortran-blink-matching-do))))
 
 (defun fortran-auto-fill ()
+  "Function to use for `normal-auto-fill-function' in Fortran mode."
   (if (> (current-column) (current-fill-column))
       (let ((cfi (fortran-calculate-indent)))
        (save-excursion
@@ -1262,8 +1487,7 @@ Return point or nil."
                       (not (fortran-line-number-indented-correctly-p))))
              (fortran-indent-to-column cfi)
            (beginning-of-line)
-           (if (and (not (looking-at fortran-comment-line-start-skip))
-                    (fortran-find-comment-start-skip))
+           (if (fortran-find-comment-start-skip)
                (fortran-indent-comment))))
        (fortran-fill)
        ;; Never leave point in left margin.
@@ -1275,8 +1499,8 @@ Return point or nil."
 (defalias 'fortran-indent-new-line 'reindent-then-newline-and-indent)
 
 (defun fortran-indent-subprogram ()
-  "Properly indent the Fortran subprogram which contains point."
-  (interactive)
+  "Properly indent the Fortran subprogram containing point."
+  (interactive "*")
   (save-excursion
     (mark-defun)
     (message "Indenting subprogram...")
@@ -1294,48 +1518,50 @@ Return point or nil."
       (setq first-statement (fortran-previous-statement))
       (if first-statement
          (setq icol fortran-minimum-statement-indent)
-       (progn
-         (if (= (point) (point-min))
-             (setq icol fortran-minimum-statement-indent)
-           (setq icol (fortran-current-line-indentation)))
-         (skip-chars-forward " \t0-9")
-         (cond ((looking-at "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?if[ \t]*(")
-                (if (or (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t_$(=a-z0-9]")
-                        (let (then-test)       ;multi-line if-then
-                          (while (and (= (forward-line 1) 0)
-                                      ;;search forward for then
-                                      (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")
-                                      (not (setq then-test
-                                                 (looking-at
-                                                  ".*then\\b[ \t]\
+        (if (= (point) (point-min))
+            (setq icol fortran-minimum-statement-indent)
+          (setq icol (fortran-current-line-indentation)))
+        (skip-chars-forward " \t0-9")
+        (cond ((looking-at "\\(\\(\\sw\\|\\s_\\)+:[ \t]*\\)?if[ \t]*(")
+               (if (or (looking-at ".*)[ \t]*then\\b[ \t]*[^ \t_$(=a-z0-9]")
+                       (let (then-test)        ; multi-line if-then
+                         (while (and (zerop (forward-line 1))
+                                     ;; Search forward for then.
+                                     (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")
+                                     (not (setq then-test
+                                                (looking-at
+                                                 ".*then\\b[ \t]\
 *[^ \t_$(=a-z0-9]")))))
-                          then-test))
-                    (setq icol (+ icol fortran-if-indent))))
-               ((looking-at "else\\(if\\)?\\b")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "select[ \t]*case[ \t](.*)")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "case[ \t]*(.*)")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "case[ \t]*default\\b")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "\\(otherwise\\|else[ \t]*where\\)\\b")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "where[ \t]*(.*)[ \t]*\n")
-                (setq icol (+ icol fortran-if-indent)))
-               ((looking-at "do\\b")
-                (setq icol (+ icol fortran-do-indent)))
-               ((looking-at
-                 "\\(structure\\|union\\|map\\|interface\\)\
+                         then-test))
+                   (setq icol (+ icol fortran-if-indent))))
+              ((looking-at "else\\(if\\)?\\b")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "select[ \t]*case[ \t](.*)")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "case[ \t]*(.*)")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "case[ \t]*default\\b")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "\\(otherwise\\|else[ \t]*where\\)\\b")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "where[ \t]*(.*)[ \t]*\n")
+               (setq icol (+ icol fortran-if-indent)))
+              ((looking-at "do\\b")
+               (setq icol (+ icol fortran-do-indent)))
+              ((looking-at
+                "\\(structure\\|union\\|map\\|interface\\)\
 \\b[ \t]*[^ \t=(a-z]")
-                (setq icol (+ icol fortran-structure-indent)))
-               ((and (looking-at fortran-end-prog-re1)
-                     (fortran-check-end-prog-re))
-                ;; Previous END resets indent to minimum
-                (setq icol fortran-minimum-statement-indent))))))
+               (setq icol (+ icol fortran-structure-indent)))
+              ((and (looking-at fortran-end-prog-re1)
+                    (fortran-check-end-prog-re))
+               ;; Previous END resets indent to minimum.
+               (setq icol fortran-minimum-statement-indent)))))
     (save-excursion
       (beginning-of-line)
       (cond ((looking-at "[ \t]*$"))
+            ;; Check for directive before comment, so as not to indent.
+           ((looking-at fortran-directive-re)
+            (setq fortran-minimum-statement-indent 0 icol 0))
            ((looking-at fortran-comment-line-start-skip)
             (cond ((eq fortran-comment-indent-style 'relative)
                    (setq icol (+ icol fortran-comment-line-extra-indent)))
@@ -1343,13 +1569,16 @@ Return point or nil."
                    (setq icol (+ fortran-minimum-statement-indent
                                  fortran-comment-line-extra-indent))))
             (setq fortran-minimum-statement-indent 0))
-           ((or (looking-at (concat "[ \t]*"
+           ((or (looking-at (concat "[ \t]*"
                                     (regexp-quote
                                      fortran-continuation-string)))
                 (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]"))
-            (setq icol (+ icol fortran-continuation-indent)))
-           ((looking-at "[ \t]*#")     ; Check for cpp directive.
-            (setq fortran-minimum-statement-indent 0 icol 0))
+             (skip-chars-forward " \t")
+             ;; Do not introduce extra whitespace into a broken string.
+             (setq icol
+                   (if (fortran-is-in-string-p (point))
+                       6
+                     (+ icol fortran-continuation-indent))))
            (first-statement)
            ((and fortran-check-all-num-for-matching-do
                  (looking-at "[ \t]*[0-9]+")
@@ -1379,6 +1608,7 @@ Return point or nil."
                    (message "Warning: `end' not in column %d.  Probably\
  an unclosed block." fortran-minimum-statement-indent))))))
     (max fortran-minimum-statement-indent icol)))
+
 \f
 (defun fortran-current-line-indentation ()
   "Indentation of current line, ignoring Fortran line number or continuation.
@@ -1404,7 +1634,7 @@ non-indentation text within the comment."
     (current-column)))
 
 (defun fortran-indent-to-column (col)
-  "Indent current line with spaces to column COL.
+  "Indent current line to column COL.
 notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
           line, and this continuation character is retained on indentation;
        2) If `fortran-continuation-string' is the first non-whitespace
@@ -1419,7 +1649,7 @@ notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
            (let* ((char (if (stringp fortran-comment-indent-char)
                             (aref fortran-comment-indent-char 0)
                           fortran-comment-indent-char))
-                  (chars (string ?  ?\t char)))
+                  (chars (string ?\s ?\t char)))
              (goto-char (match-end 0))
              (skip-chars-backward chars)
              (delete-region (point) (progn (skip-chars-forward chars)
@@ -1429,7 +1659,7 @@ notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
          (if indent-tabs-mode
              (goto-char (match-end 0))
            (delete-char 2)
-           (insert-char ?  5)
+           (insert-char ?\s 5)
            (insert fortran-continuation-string))
        (if (looking-at " \\{5\\}[^ 0\n]")
            (if indent-tabs-mode
@@ -1437,8 +1667,8 @@ notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
                       (insert ?\t (fortran-numerical-continuation-char) 1))
              (forward-char 6))
          (delete-horizontal-space)
-         ;; Put line number in columns 0-4
-         ;; or put continuation character in column 5.
+         ;; Put line number in columns 0-4, or
+          ;; continuation character in column 5.
          (cond ((eobp))
                ((looking-at (regexp-quote fortran-continuation-string))
                 (if indent-tabs-mode
@@ -1462,13 +1692,11 @@ notes: 1) A non-zero/non-blank character in column 5 indicates a continuation
       (delete-horizontal-space)
       (indent-to col)
       ;; Indent any comment following code on the same line.
-      (if (and comment-start-skip
-              (fortran-find-comment-start-skip))
-         (progn (goto-char (match-beginning 0))
-                (if (not (= (current-column)
-                            (fortran-comment-indent)))
-                    (progn (delete-horizontal-space)
-                           (indent-to (fortran-comment-indent)))))))))
+      (when (fortran-find-comment-start-skip)
+        (goto-char (match-beginning 0))
+        (unless (= (current-column) (fortran-comment-indent))
+          (delete-horizontal-space)
+          (indent-to (fortran-comment-indent)))))))
 
 (defun fortran-line-number-indented-correctly-p ()
   "Return t if current line's line number is correctly indented.
@@ -1488,51 +1716,50 @@ Otherwise return nil."
        charnum)
     (save-excursion
       (beginning-of-line)
-      (if (looking-at "[ \t]*[0-9]+")
-         (progn
-           (skip-chars-forward " \t")
-           (skip-chars-forward "0")    ;skip past leading zeros
-           (setq charnum
-                 (buffer-substring (point) (progn
-                                             (skip-chars-forward "0-9")
-                                             (point))))
-           (beginning-of-line)
-           (save-restriction
-             (save-excursion
-               (narrow-to-defun)
-               (and (re-search-backward
-                     (concat
-                      "\\(^[ \t0-9]*do[ \t]*0*"
-                      charnum "\\b\\)\\|" "\\(^[ \t]*0*"
-                      charnum "\\b\\)")
-                     nil t)
-                    (looking-at
-                     (concat "^[ \t0-9]*do[ \t]*0*"
-                             charnum))))))))))
-
-(defun fortran-find-comment-start-skip ()
+      (when (looking-at "[ \t]*[0-9]+")
+        (skip-chars-forward " \t")
+        (skip-chars-forward "0")       ; skip past leading zeros
+        (setq charnum
+              (buffer-substring (point) (progn
+                                          (skip-chars-forward "0-9")
+                                          (point))))
+        (beginning-of-line)
+        (save-restriction
+          (save-excursion
+            (narrow-to-defun)
+            (and (re-search-backward
+                  (concat
+                   "\\(^[ \t0-9]*do[ \t]*0*"
+                   charnum "\\b\\)\\|" "\\(^[ \t]*0*"
+                   charnum "\\b\\)")
+                  nil t)
+                 (looking-at
+                  (concat "^[ \t0-9]*do[ \t]*0*"
+                          charnum)))))))))
+
+(defun fortran-find-comment-start-skip (&optional all)
   "Move to past `comment-start-skip' found on current line.
-Return t if `comment-start-skip' found, nil if not."
-  ;; In order to move point only if comment-start-skip is found, this
-  ;; one uses a lot of save-excursions.  Note that re-search-forward
-  ;; moves point even if comment-start-skip is inside a string-constant.
-  ;; Some code expects certain values for match-beginning and end.
-  (interactive)
-  (if (and comment-start-skip
-          (save-excursion
-            (re-search-forward comment-start-skip (line-end-position) t)))
-      (let ((save-match-beginning (match-beginning 0))
-           (save-match-end (match-end 0)))
-       (if (fortran-is-in-string-p (match-beginning 0))
-           (save-excursion
-             (goto-char save-match-end)
-             (fortran-find-comment-start-skip)) ; recurse for rest of line
-         (goto-char save-match-beginning)
-         (re-search-forward comment-start-skip (line-end-position) t)
-         (goto-char (match-end 0))
-         t))))
-
-;;From: ralf@up3aud1.gwdg.de (Ralf Fassel)
+Return non-nil if `comment-start-skip' found, nil if not.
+If ALL is nil, only match comments that start in column > 0."
+  ;; Hopefully at some point we can just use the line below!  -stef
+  ;; (comment-search-forward (line-end-position) t))
+  (when (or all comment-start-skip)
+    (let ((pos (point))
+         (css (if comment-start-skip
+                  (concat fortran-comment-line-start-skip
+                          "\\|" comment-start-skip)
+                fortran-comment-line-start-skip)))
+      (when (re-search-forward css (line-end-position) t)
+       (if (and (or all (> (match-beginning 0) (line-beginning-position)))
+                (or (save-match-data
+                      (not (fortran-is-in-string-p (match-beginning 0))))
+                    ;; Recurse for rest of line.
+                    (fortran-find-comment-start-skip all)))
+           (point)
+         (goto-char pos)
+         nil)))))
+
+;; From: ralf@up3aud1.gwdg.de (Ralf Fassel)
 ;; Test if TAB format continuation lines work.
 (defun fortran-is-in-string-p (where)
   "Return non-nil iff WHERE (a buffer position) is inside a Fortran string."
@@ -1543,18 +1770,17 @@ Return t if `comment-start-skip' found, nil if not."
      ((save-excursion                  ; comment lines too
        (beginning-of-line)
        (looking-at fortran-comment-line-start-skip)) nil)
-     (t (let (;; ok, serious now. Init some local vars:
-             (parse-state '(0 nil nil nil nil nil 0))
+     (t (let ((parse-state '(0 nil nil nil nil nil 0))
              (quoted-comment-start (if comment-start
                                        (regexp-quote comment-start)))
              (not-done t)
              parse-limit end-of-line)
-         ;; move to start of current statement
+         ;; Move to start of current statement.
          (fortran-next-statement)
          (fortran-previous-statement)
-         ;; now parse up to WHERE
+         ;; Now parse up to WHERE.
          (while not-done
-           (if (or ;; skip to next line if:
+           (if (or ;; Skip to next line if:
                 ;; - comment line?
                 (looking-at fortran-comment-line-start-skip)
                 ;; - at end of line?
@@ -1567,119 +1793,140 @@ Return t if `comment-start-skip' found, nil if not."
                (if (> (forward-line) 0)
                    (setq not-done nil))
              ;; else:
-             ;; if we are at beginning of code line, skip any
+             ;; If we are at beginning of code line, skip any
              ;; whitespace, labels and tab continuation markers.
              (if (bolp) (skip-chars-forward " \t0-9"))
-             ;; if we are in column <= 5 now, check for continuation char
+             ;; If we are in column <= 5 now, check for continuation char.
              (cond ((= 5 (current-column)) (forward-char 1))
                    ((and (< (current-column) 5)
                          (equal fortran-continuation-string
                                 (char-to-string (following-char)))
                          (forward-char 1))))
-             ;; find out parse-limit from here
+             ;; Find out parse-limit from here.
              (setq end-of-line (line-end-position))
              (setq parse-limit (min where end-of-line))
-             ;; parse max up to comment-start, if non-nil and in current line
+             ;; Parse max up to comment-start, if non-nil and in current line.
              (if comment-start
                  (save-excursion
                    (if (re-search-forward quoted-comment-start end-of-line t)
                        (setq parse-limit (min (point) parse-limit)))))
-             ;; now parse if still in limits
+             ;; Now parse if still in limits.
              (if (< (point) where)
                  (setq parse-state (parse-partial-sexp
                                     (point) parse-limit nil nil parse-state))
                (setq not-done nil))))
-         ;; result is
+         ;; Result.
          (nth 3 parse-state))))))
 
 ;; From old version.
 (defalias 'fortran-auto-fill-mode 'auto-fill-mode)
 
 (defun fortran-fill ()
+  "Fill the current line at an appropriate point(s)."
   (let* ((auto-fill-function #'fortran-auto-fill)
         (opoint (point))
         (bol (line-beginning-position))
         (eol (line-end-position))
         (bos (min eol (+ bol (fortran-current-line-indentation))))
+         ;; If in a string at fill-column, break it either before the
+         ;; initial quote, or at fill-col (if string is too long).
         (quote
          (save-excursion
            (goto-char bol)
-           (if (looking-at fortran-comment-line-start-skip)
-               nil                     ; OK to break quotes on comment lines.
-             (move-to-column fill-column)
-             (if (fortran-is-in-string-p (point))
-                 (save-excursion (re-search-backward "\\S\"\\s\"\\S\"" bol t)
-                                 (if fortran-break-before-delimiters
-                                     (point)
-                                   (1+ (point))))))))
-        ;; decide where to split the line. If a position for a quoted
+           ;; OK to break quotes on comment lines.
+           (unless (looking-at fortran-comment-line-start-skip)
+              (let (fcpoint start)
+                (move-to-column fill-column)
+                (when (fortran-is-in-string-p (setq fcpoint (point)))
+                  (save-excursion
+                    (re-search-backward "\\S\"\\s\"\\S\"?" bol t)
+                    (setq start
+                          (if fortran-break-before-delimiters
+                              (point)
+                            (1+ (point)))))
+                  (if (re-search-forward "\\S\"\\s\"\\S\"" eol t)
+                      (backward-char 2))
+                  ;; If the current string is longer than (fill-column
+                  ;; - 6) chars, break it at the fill column (else
+                  ;; infinite loop).
+                  (if (> (- (point) start)
+                         (- fill-column 6 fortran-continuation-indent))
+                      fcpoint
+                    start))))))
+        ;; Decide where to split the line. If a position for a quoted
         ;; string was found above then use that, else break the line
-        ;; before the last delimiter.
-        ;; Delimiters are whitespace, commas, and operators.
-        ;; Will break before a pair of *'s.
+        ;; before/after the last delimiter.
         (fill-point
          (or quote
              (save-excursion
-               (move-to-column (1+ fill-column))
-               (skip-chars-backward "^ \t\n,'+-/*=)"
-;;;             (if fortran-break-before-delimiters
-;;;                 "^ \t\n,'+-/*=" "^ \t\n,'+-/*=)")
-                )
-               (if (<= (point) (1+ bos))
-                   (progn
-                     (move-to-column (1+ fill-column))
-                     ;;what is this doing???
-                     (if (not (re-search-forward "[\t\n,'+-/*)=]" eol t))
-                         (goto-char bol))))
+                ;; If f-b-b-d is t, have an extra column to play with,
+                ;; since delimiter gets shifted to new line.
+                (move-to-column (if fortran-break-before-delimiters
+                                    (1+ fill-column)
+                                  fill-column))
+                (let ((repeat t))
+                  (while repeat
+                    (setq repeat nil)
+                    ;; Adapted from f90-find-breakpoint.
+                    (re-search-backward fortran-break-delimiters-re bol)
+                    (if (not fortran-break-before-delimiters)
+                        (if (looking-at fortran-no-break-re)
+                            ;; Deal with cases such as "**" split over
+                            ;; fill-col. Simpler alternative would be
+                            ;; to start from (1- fill-column) above.
+                            (if (> (+ 2 (current-column)) fill-column)
+                                (setq repeat t)
+                              (forward-char 2))
+                          (forward-char 1))
+                      (backward-char)
+                      (or (looking-at fortran-no-break-re)
+                          (forward-char)))))
+                ;; Line indented beyond fill-column?
+               (when (<= (point) bos)
+                  (move-to-column (1+ fill-column))
+                  ;; What is this doing???
+                  (or (re-search-forward "[\t\n,'+-/*)=]" eol t)
+                      (goto-char bol)))
                (if (bolp)
-                   (re-search-forward "[ \t]" opoint t)
-                 (backward-char)
-                 (if (looking-at "\\s\"")
-                     (forward-char)
-                   (skip-chars-backward " \t\*")))
-               (if fortran-break-before-delimiters
-                   (point)
-                 (1+ (point)))))))
-    ;; if we are in an in-line comment, don't break unless the
+                   (re-search-forward "[ \t]" opoint t))
+                (point)))))
+    ;; If we are in an in-line comment, don't break unless the
     ;; line of code is longer than it should be. Otherwise
     ;; break the line at the column computed above.
     ;;
-    ;; Need to use fortran-find-comment-start-skip to make sure that quoted !'s
-    ;; don't prevent a break.
-    (if (not (or (save-excursion
-                  (if (and comment-start-skip
-                           (re-search-backward comment-start-skip bol t)
-                           (not (fortran-is-in-string-p (point))))
-                      (progn
-                        (skip-chars-backward " \t")
-                        (< (current-column) (1+ fill-column)))))
-                (save-excursion
-                  (goto-char fill-point)
-                  (bolp))))
-       (when (> (save-excursion
-                  (goto-char opoint)
-                  (current-column))
-                (min (1+ fill-column)
-                     (+ (fortran-calculate-indent)
-                        fortran-continuation-indent)))
-         (goto-char fill-point)
-         (fortran-break-line)
-         (end-of-line)))))
+    ;; Need to use fortran-find-comment-start-skip to make sure that
+    ;; quoted !'s don't prevent a break.
+    (when (and (save-excursion
+                (beginning-of-line)
+                (if (not (fortran-find-comment-start-skip))
+                     t
+                  (goto-char (match-beginning 0))
+                  (>= (point) fill-point)))
+              (save-excursion
+                (goto-char fill-point)
+                (not (bolp)))
+              (> (save-excursion
+                   (goto-char opoint)
+                   (current-column))
+                 (min (1+ fill-column)
+                      (+ (fortran-calculate-indent)
+                         fortran-continuation-indent))))
+      (goto-char fill-point)
+      (fortran-break-line)
+      (end-of-line))))
 
 (defun fortran-break-line ()
+  "Call `fortran-split-line'.  Joins continuation lines first, then refills."
   (let ((opoint (point))
        (bol (line-beginning-position))
-       (eol (line-end-position))
-       (comment-string nil))
-    (save-excursion
-      (if (and comment-start-skip (fortran-find-comment-start-skip))
-         (progn
-           (re-search-backward comment-start-skip bol t)
-           (setq comment-string (buffer-substring (point) eol))
-           (delete-region (point) eol))))
-    ;; Forward line 1 really needs to go to next non white line
+       (comment-string
+        (save-excursion
+          (if (fortran-find-comment-start-skip)
+              (delete-and-extract-region
+               (match-beginning 0) (line-end-position))))))
+    ;; Forward line 1 really needs to go to next non white line.
     (if (save-excursion (forward-line)
-                       (or (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]")))
+                       (looking-at " \\{5\\}[^ 0\n]\\|\t[1-9]"))
        (progn
          (end-of-line)
          (delete-region (point) (match-end 0))
@@ -1696,12 +1943,11 @@ Return t if `comment-start-skip' found, nil if not."
 
 (defun fortran-analyze-file-format ()
   "Return nil if fixed format is used, t if TAB formatting is used.
-Use `fortran-tab-mode-default' if no non-comment statements are found in the
-file before the end or the first `fortran-analyze-depth' lines."
+Use `fortran-tab-mode-default' if no non-comment statements are found
+before the end or in the first `fortran-analyze-depth' lines."
   (let ((i 0))
     (save-excursion
       (goto-char (point-min))
-      (setq i 0)
       (while (not (or
                   (eobp)
                   (eq (char-after) ?\t)
@@ -1712,87 +1958,48 @@ file before the end or the first `fortran-analyze-depth' lines."
       (cond
        ((eq (char-after) ?\t) t)
        ((looking-at " \\{6\\}") nil)
-       (fortran-tab-mode-default t)
-       (t nil)))))
-
-(or (assq 'fortran-tab-mode-string minor-mode-alist)
-    (setq minor-mode-alist (cons
-                           '(fortran-tab-mode-string
-                             (indent-tabs-mode fortran-tab-mode-string))
-                           minor-mode-alist)))
+       (t fortran-tab-mode-default)))))
 
 (defun fortran-fill-paragraph (&optional justify)
   "Fill surrounding comment block as paragraphs, else fill statement.
-Intended as the value of `fill-paragraph-function'."
-  (interactive "P")
-  (save-excursion
-    (beginning-of-line)
-    (if (not (looking-at fortran-comment-line-start-skip))
-       (fortran-fill-statement)
-       ;; We're in a comment block.  Find the start and end of a
-       ;; paragraph, delimited either by non-comment lines or empty
-       ;; comments.  (Get positions as markers, since the
-       ;; `indent-region' below can shift the block's end).
-       (let* ((non-empty-comment 
-               (concat fortran-comment-line-start-skip "[^ \t\n]"))
-              (start (save-excursion
-                       ;; Find (start of) first line.
-                       (while (and (zerop (forward-line -1))
-                                   (looking-at non-empty-comment)))
-                       (or (looking-at non-empty-comment)
-                           (forward-line)) ; overshot
-                       (point-marker)))
-              (end (save-excursion
-                     ;; Find start of first line past region to fill.
-                     (while (progn 
-                              (forward-line)
-                              (looking-at non-empty-comment)))
-                     (point-marker))))
-         ;; Indent the block, find the string comprising the effective
-         ;; comment start skip and use that as a fill-prefix for
-         ;; filling the region.
-         (indent-region start end nil)
-         (let ((paragraph-ignore-fill-prefix nil)
-               (fill-prefix (progn
-                              (beginning-of-line)
-                              (looking-at fortran-comment-line-start-skip)
-                              (match-string 0))))
-           (let (fill-paragraph-function)
-             (fill-region start end justify))) ; with normal `fill-paragraph'
-         (set-marker start nil)
-         (set-marker end nil))))
-  t)
+Intended as the value of `fill-paragraph-function'.
+A comment block is filled by calling `fill-comment-paragraph' with
+argument JUSTIFY, otherwise `fortran-fill-statement' is called.
+Always returns non-nil (to prevent `fill-paragraph' being called)."
+  (interactive "*P")
+  (or (fill-comment-paragraph justify)
+      (fortran-fill-statement)
+      t))
 
 (defun fortran-fill-statement ()
-  "Fill a fortran statement up to `fill-column'."
-  (interactive)
+  "Fill a Fortran statement up to `fill-column'."
+  (interactive "*")
   (let ((auto-fill-function #'fortran-auto-fill))
-    (if (not (save-excursion
-              (beginning-of-line)
-              (or (looking-at "[ \t]*$")
-                  (looking-at fortran-comment-line-start-skip)
-                  (and comment-start-skip
-                       (looking-at (concat "[ \t]*"
-                                           comment-start-skip))))))
-       (save-excursion
-         ;; Find beginning of statement.
-         (fortran-next-statement)
-         (fortran-previous-statement)
-         ;; Re-indent initially.
-         (fortran-indent-line)
-         ;; Replace newline plus continuation field plus indentation with
-         ;; single space.
-         (while (progn
-                  (forward-line)
-                  (fortran-remove-continuation)))
-         (fortran-previous-statement)))
+    (unless (save-excursion
+              (beginning-of-line)
+              (or (looking-at "[ \t]*$")
+                  (looking-at fortran-comment-line-start-skip)
+                  (and comment-start-skip
+                       (looking-at (concat "[ \t]*" comment-start-skip)))))
+      (save-excursion
+        ;; Find beginning of statement.
+        (fortran-next-statement)
+        (fortran-previous-statement)
+        ;; Re-indent initially.
+        (fortran-indent-line)
+        ;; Replace newline plus continuation field plus indentation with
+        ;; single space.
+        (while (progn
+                 (forward-line)
+                 (fortran-remove-continuation)))
+        (fortran-previous-statement)))
     (fortran-indent-line)))
 
-(defun fortran-strip-sqeuence-nos (&optional do-space)
+(defun fortran-strip-sequence-nos (&optional do-space)
   "Delete all text in column 72 and up (assumed to be sequence numbers).
 Normally also deletes trailing whitespace after stripping such text.
 Supplying prefix arg DO-SPACE prevents stripping the whitespace."
-  (interactive "p")
+  (interactive "*p")
   (save-excursion
     (goto-char (point-min))
     (while (re-search-forward "^.\\{72\\}\\(.*\\)" nil t)
@@ -1803,29 +2010,31 @@ Supplying prefix arg DO-SPACE prevents stripping the whitespace."
 ;; for it.
 (defun fortran-current-defun ()
   "Function to use for `add-log-current-defun-function' in Fortran mode."
-  ;; We must be inside function body for this to work.
-  (fortran-beginning-of-subprogram)
-  (let ((case-fold-search t))          ; case-insensitive
-    ;; search for fortran subprogram start
-    (if (re-search-forward
-        (concat "^[ \t]*\\(program\\|subroutine\\|function"
-                "\\|[ \ta-z0-9*()]*[ \t]+function\\|"
-                "\\(block[ \t]*data\\)\\)")
-        (save-excursion (fortran-end-of-subprogram)
-                        (point))
-        t)
-       (or (match-string-no-properties 2)
-           (progn
-             ;; move to EOL or before first left paren
-             (if (re-search-forward "[(\n]" nil t)
-                 (progn (backward-char)
-                        (skip-chars-backward " \t"))
-               (end-of-line))
-             ;; Use the name preceding that.
-             (buffer-substring-no-properties (point) (progn (backward-sexp)
-                                                            (point)))))
-      "main")))
+  (save-excursion
+    ;; We must be inside function body for this to work.
+    (fortran-beginning-of-subprogram)
+    (let ((case-fold-search t))                ; case-insensitive
+      ;; Search for fortran subprogram start.
+      (if (re-search-forward
+           (concat "^[ \t]*\\(program\\|subroutine\\|function"
+                   "\\|[ \ta-z0-9*()]*[ \t]+function\\|"
+                   "\\(block[ \t]*data\\)\\)")
+           (save-excursion (fortran-end-of-subprogram)
+                           (point))
+           t)
+          (or (match-string-no-properties 2)
+              (progn
+                ;; Move to EOL or before first left paren.
+                (if (re-search-forward "[(\n]" nil t)
+                    (progn (backward-char)
+                           (skip-chars-backward " \t"))
+                  (end-of-line))
+                ;; Use the name preceding that.
+                (buffer-substring-no-properties (point) (progn (backward-sexp)
+                                                               (point)))))
+        "main"))))
 
 (provide 'fortran)
 
+;;; arch-tag: 74935096-21c4-4cab-8ee5-6ef16090dc04
 ;;; fortran.el ends here