Don't overflow if computing approximate percentage

* lisp/align.el (align-region):
* lisp/cedet/semantic.el (semantic-repeat-parse-whole-stream):
* lisp/cedet/semantic/wisent.el (wisent-parse-region):
* lisp/cus-edit.el (custom-buffer-create-internal):
* lisp/emacs-lisp/checkdoc.el (checkdoc-interactive-ispell-loop)
(checkdoc-message-interactive-ispell-loop, checkdoc-next-error)
(checkdoc-next-message-error):
* lisp/emacs-lisp/eieio-opt.el (eieio-display-method-list):
* lisp/epa.el (epa-progress-callback-function):
* lisp/erc/erc-dcc.el (erc-dcc-do-LIST-command):
* lisp/ffap.el (ffap-menu-rescan):
* lisp/gnus/nnbabyl.el (nnbabyl-retrieve-headers):
* lisp/gnus/nndiary.el (nndiary-retrieve-headers):
* lisp/gnus/nneething.el (nneething-retrieve-headers):
* lisp/gnus/nnmbox.el (nnmbox-retrieve-headers):
* lisp/gnus/nnmh.el (nnmh-retrieve-headers):
* lisp/gnus/nnml.el (nnml-retrieve-headers):
* lisp/gnus/nnspool.el (nnspool-retrieve-headers):
* lisp/gnus/nntp.el (nntp-retrieve-headers)
(nntp-retrieve-articles):
* lisp/imenu.el (imenu--relative-position):
* lisp/international/ja-dic-cnv.el (skkdic-collect-okuri-nasi)
(skkdic-convert-okuri-nasi):
* lisp/net/ange-ftp.el (ange-ftp-process-handle-hash):
* lisp/nxml/rng-valid.el (rng-compute-mode-line-string):
* lisp/org/org-list.el (org-update-checkbox-count):
* lisp/org/org.el (org-table-map-tables)
(org-update-parent-todo-statistics):
* lisp/play/decipher.el (decipher-insert-frequency-counts)
(decipher-analyze-buffer):
* lisp/profiler.el (profiler-format-percent):
* lisp/progmodes/cc-cmds.el (c-progress-update):
* lisp/progmodes/cpp.el (cpp-highlight-buffer):
* lisp/progmodes/idlwave.el (idlwave-convert-xml-system-routine-info)
(idlwave-list-load-path-shadows):
* lisp/progmodes/opascal.el (opascal-step-progress):
* lisp/progmodes/vhdl-mode.el (vhdl-update-progress-info)
(vhdl-scan-directory-contents):
* lisp/textmodes/bibtex.el (bibtex-progress-message):
* lisp/textmodes/flyspell.el (flyspell-small-region)
(flyspell-external-point-words):
* lisp/textmodes/table.el (table-recognize):
Prefer (floor (* 100.0 NUMERATOR) DENOMINATOR) when calculating
progress-report percentages and the like.  This avoids problems
if (* 100 NUMERATOR) would overflow.
* lisp/gnus/gnus-registry.el (gnus-registry-import-eld):
* lisp/gnus/registry.el (registry-reindex):
Use (* 100.0 ...) rather than (* 100 ...) to avoid int overflow issues.
* lisp/descr-text.el (describe-char):
* lisp/org/org-colview.el (org-nofm-to-completion):
* lisp/ps-print.el (ps-plot):
* lisp/simple.el (what-cursor-position):
Prefer (round (* 100.0 NUMERATOR) DENOMINATOR) to a
more-complicated and less-accurate approximation.

39 files changed, 74 insertions, 91 deletions

diff --git a/lisp/align.el b/lisp/align.el
index 82a55b0feac..ad5be2ae74d 100644
--- a/lisp/align.el
+++ b/lisp/align.el
@@ -1437,12 +1437,12 @@ aligner would have dealt with are."
                               (message
                                "Aligning `%s' (rule %d of %d) %d%%..."
                                (symbol-name symbol) rule-index rule-count
-                               (/ (* (- (point) real-beg) 100)
-                                  (- end-mark real-beg)))
+                               (floor (* (- (point) real-beg) 100.0)
+                                      (- end-mark real-beg)))
                             (message
                              "Aligning %d%%..."
-                             (/ (* (- (point) real-beg) 100)
-                                (- end-mark real-beg))))))
+                             (floor (* (- (point) real-beg) 100.0)
+                                    (- end-mark real-beg))))))
 
                     ;; if the search ended us on the beginning of
                     ;; the next line, move back to the end of the
diff --git a/lisp/cedet/semantic.el b/lisp/cedet/semantic.el
index 81a97884554..290cd907beb 100644
--- a/lisp/cedet/semantic.el
+++ b/lisp/cedet/semantic.el
@@ -769,8 +769,8 @@ This function returns semantic tags without overlays."
                (eq semantic-working-type 'percent)
                (progress-reporter-update
                 semantic--progress-reporter
-                (/ (* 100 (semantic-lex-token-start (car stream)))
-                   (point-max))))))
+                (floor (* 100.0 (semantic-lex-token-start (car stream)))
+                       (point-max))))))
     result))
 
 ;;; Parsing Warnings:
diff --git a/lisp/cedet/semantic/wisent.el b/lisp/cedet/semantic/wisent.el
index dfa533c7b26..761bc6812da 100644
--- a/lisp/cedet/semantic/wisent.el
+++ b/lisp/cedet/semantic/wisent.el
@@ -322,9 +322,9 @@ the standard function `semantic-parse-region'."
                semantic--progress-reporter
                (progress-reporter-update
                 semantic--progress-reporter
-                (/ (* 100 (semantic-lex-token-start
-                           (car wisent-lex-istream)))
-                   (point-max))))))
+                (floor (* 100.0 (semantic-lex-token-start
+                                 (car wisent-lex-istream)))
+                       (point-max))))))
     ;; Return parse tree
     (nreverse ptree)))
 
diff --git a/lisp/cus-edit.el b/lisp/cus-edit.el
index 1d9a9d6d426..a8d1c97e37a 100644
--- a/lisp/cus-edit.el
+++ b/lisp/cus-edit.el
@@ -1709,7 +1709,7 @@ Operate on all settings in this buffer:\n"))
             (mapcar (lambda (entry)
                       (prog2
                           (message "Creating customization items ...%2d%%"
-                                   (/ (* 100.0 count) length))
+                                   (floor (* 100.0 count) length))
                           (widget-create (nth 1 entry)
                                          :tag (custom-unlispify-tag-name
                                                (nth 0 entry))
diff --git a/lisp/descr-text.el b/lisp/descr-text.el
index a0b9ddfe2c9..71233d406e1 100644
--- a/lisp/descr-text.el
+++ b/lisp/descr-text.el
@@ -542,9 +542,7 @@ relevant to POS."
                ,(let* ((beg      (point-min))
                        (end      (point-max))
                        (total    (buffer-size))
-                       (percent  (if (> total 50000) ; Avoid overflow multiplying by 100
-                                     (/ (+ (/ total 200) (1- pos))  (max (/ total 100) 1))
-                                   (/ (+ (/ total 2) (* 100 (1- pos)))  (max total 1))))
+                       (percent  (round (* 100.0 (1- pos)) (max total 1)))
                        (hscroll  (if (= (window-hscroll) 0)
                                      ""
                                    (format ", Hscroll: %d" (window-hscroll))))
diff --git a/lisp/emacs-lisp/checkdoc.el b/lisp/emacs-lisp/checkdoc.el
index 0b451ef6b2a..c22aff4cbca 100644
--- a/lisp/emacs-lisp/checkdoc.el
+++ b/lisp/emacs-lisp/checkdoc.el
@@ -747,7 +747,7 @@ buffer, otherwise searching starts at START-HERE."
       ;; Loop over docstrings.
       (while (checkdoc-next-docstring)
         (message "Searching for doc string spell error...%d%%"
-                 (/ (* 100 (point)) (point-max)))
+                 (floor (* 100.0 (point)) (point-max)))
         (if (looking-at "\"")
             (checkdoc-ispell-docstring-engine
              (save-excursion (forward-sexp 1) (point-marker)))))
@@ -767,7 +767,7 @@ buffer, otherwise searching starts at START-HERE."
       ;; Loop over message strings.
       (while (checkdoc-message-text-next-string (point-max))
         (message "Searching for message string spell error...%d%%"
-                 (/ (* 100 (point)) (point-max)))
+                 (floor (* 100.0 (point)) (point-max)))
         (if (looking-at "\"")
             (checkdoc-ispell-docstring-engine
              (save-excursion (forward-sexp 1) (point-marker)))))
@@ -791,7 +791,7 @@ perform the fix."
       (condition-case nil
           (while (and (not msg) (checkdoc-next-docstring))
             (message "Searching for doc string error...%d%%"
-                     (/ (* 100 (point)) (point-max)))
+                     (floor (* 100.0 (point)) (point-max)))
             (if (setq msg (checkdoc-this-string-valid))
                 (setq msg (cons msg (point)))))
         ;; Quit.. restore position,  Other errors, leave alone
@@ -813,7 +813,7 @@ assumes that the cursor is already positioned to perform the fix."
                       (setq type
                             (checkdoc-message-text-next-string (point-max))))
             (message "Searching for message string error...%d%%"
-                     (/ (* 100 (point)) (point-max)))
+                     (floor (* 100.0 (point)) (point-max)))
             (if (setq msg (checkdoc-message-text-engine type))
                 (setq msg (cons msg (point)))))
         ;; Quit.. restore position,  Other errors, leave alone
diff --git a/lisp/emacs-lisp/eieio-opt.el b/lisp/emacs-lisp/eieio-opt.el
index 9ecc59434e1..0b003360ed5 100644
--- a/lisp/emacs-lisp/eieio-opt.el
+++ b/lisp/emacs-lisp/eieio-opt.el
@@ -243,13 +243,13 @@ are not abstract."
     (princ "Methods Primary Only: ")
     (prin1 primaryonly)
     (princ "\t")
-    (princ (format "%d" (* (/ (float primaryonly) (float methidx)) 100)))
+    (princ (format "%d" (floor (* 100.0 primaryonly) methidx)))
     (princ "% of total methods")
     (terpri)
     (princ "Only One Primary Impl: ")
     (prin1 oneprimary)
     (princ "\t")
-    (princ (format "%d" (* (/ (float oneprimary) (float primaryonly)) 100)))
+    (princ (format "%d" (floor (* 100.0 oneprimary) primaryonly)))
     (princ "% of total primary methods")
     (terpri)
     ))
diff --git a/lisp/epa.el b/lisp/epa.el
index d3fec73ecf4..f6d60459777 100644
--- a/lisp/epa.el
+++ b/lisp/epa.el
@@ -658,7 +658,7 @@ If SECRET is non-nil, list secret keys instead of public keys."
         (if (= current total)
             (message "%s...done" prompt)
           (message "%s...%d%%" prompt
-                   (floor (* (/ current (float total)) 100))))
+                   (floor (* 100.0 current) total)))
       (message "%s..." prompt))))
 
 (defun epa-read-file-name (input)
diff --git a/lisp/erc/erc-dcc.el b/lisp/erc/erc-dcc.el
index 182f1e05921..d4d005d8345 100644
--- a/lisp/erc/erc-dcc.el
+++ b/lisp/erc/erc-dcc.el
@@ -594,14 +594,9 @@ It lists the current state of `erc-dcc-list' in an easy to read manner."
                                             (get-buffer (plist-get elt :file))
                                           (+ (buffer-size) 0.0
                                              erc-dcc-byte-count))))
-                        (concat " ("
-                                (if (= byte-count 0)
-                                    "0"
-                                  (number-to-string
-                                   (truncate
-                                    (* 100
-                                       (/ byte-count (plist-get elt :size))))))
-                                "%)"))))
+                        (format " (%d%%)"
+                                (floor (* 100.0 byte-count)
+                                       (plist-get elt :size))))))
        ?f (or (and (plist-member elt :file) (plist-get elt :file)) "")))
     (erc-display-message
      nil 'notice 'active
diff --git a/lisp/ffap.el b/lisp/ffap.el
index 81cba07d4c3..c0ab1af80f5 100644
--- a/lisp/ffap.el
+++ b/lisp/ffap.el
@@ -1568,7 +1568,7 @@ Applies `ffap-menu-text-plist' text properties at all matches."
             (add-text-properties (car ffap-string-at-point-region) (point)
                                  ffap-menu-text-plist)
             (message "Scanning...%2d%% <%s>"
-                     (/ (* 100 (- (point) (point-min))) range) item)))
+                     (floor (* 100.0 (- (point) (point-min))) range) item)))
       (or mod (restore-buffer-modified-p nil))))
   (message "Scanning...done")
   ;; Remove duplicates.
diff --git a/lisp/gnus/gnus-registry.el b/lisp/gnus/gnus-registry.el
index 0cb596012c7..50443973a8d 100644
--- a/lisp/gnus/gnus-registry.el
+++ b/lisp/gnus/gnus-registry.el
@@ -1100,7 +1100,7 @@ only the last one's marks are returned."
         (when (and (< 0 expected)
                    (= 0 (mod count 100)))
           (message "importing: %d of %d (%.2f%%)"
-                   count expected (/ (* 100 count) expected)))
+                   count expected (/ (* 100.0 count) expected)))
         (setq entry (car-safe old)
               old (cdr-safe old))
         (let* ((id (car-safe entry))
diff --git a/lisp/gnus/nnbabyl.el b/lisp/gnus/nnbabyl.el
index d060c2a80dd..ae417a0ffe8 100644
--- a/lisp/gnus/nnbabyl.el
+++ b/lisp/gnus/nnbabyl.el
@@ -105,7 +105,7 @@
              (> number nnmail-large-newsgroup)
              (zerop (% (incf count) 20))
              (nnheader-message 5 "nnbabyl: Receiving headers... %d%%"
-                               (/ (* count 100) number))))
+                               (floor (* count 100.0) number))))
 
       (and (numberp nnmail-large-newsgroup)
            (> number nnmail-large-newsgroup)
diff --git a/lisp/gnus/nndiary.el b/lisp/gnus/nndiary.el
index 027d8888705..31344382029 100644
--- a/lisp/gnus/nndiary.el
+++ b/lisp/gnus/nndiary.el
@@ -423,7 +423,7 @@ all.  This may very well take some time.")
                    (> number nnmail-large-newsgroup)
                    (zerop (% count 20))
                    (nnheader-message 6 "nndiary: Receiving headers... %d%%"
-                                     (/ (* count 100) number))))
+                                     (floor (* count 100.0) number))))
 
             (and (numberp nnmail-large-newsgroup)
                  (> number nnmail-large-newsgroup)
diff --git a/lisp/gnus/nneething.el b/lisp/gnus/nneething.el
index 183e3967632..0d9044fb712 100644
--- a/lisp/gnus/nneething.el
+++ b/lisp/gnus/nneething.el
@@ -106,7 +106,7 @@ included.")
           (and large
                (zerop (% count 20))
                (nnheader-message 5 "nneething: Receiving headers... %d%%"
-                                 (/ (* count 100) number))))
+                                 (floor (* count 100.0) number))))
 
         (when large
           (nnheader-message 5 "nneething: Receiving headers...done"))
diff --git a/lisp/gnus/nnmbox.el b/lisp/gnus/nnmbox.el
index 78983a5cfef..a70a0395f37 100644
--- a/lisp/gnus/nnmbox.el
+++ b/lisp/gnus/nnmbox.el
@@ -106,7 +106,7 @@
              (> number nnmail-large-newsgroup)
              (zerop (% count 20))
              (nnheader-message 5 "nnmbox: Receiving headers... %d%%"
-                               (/ (* count 100) number))))
+                               (floor (* count 100.0) number))))
 
       (and (numberp nnmail-large-newsgroup)
            (> number nnmail-large-newsgroup)
diff --git a/lisp/gnus/nnmh.el b/lisp/gnus/nnmh.el
index 04270a554cf..cdbf38ae62d 100644
--- a/lisp/gnus/nnmh.el
+++ b/lisp/gnus/nnmh.el
@@ -109,7 +109,7 @@ as unread by Gnus.")
           (and large
                (zerop (% count 20))
                (nnheader-message 5 "nnmh: Receiving headers... %d%%"
-                                 (/ (* count 100) number))))
+                                 (floor (* count 100.0) number))))
 
         (when large
           (nnheader-message 5 "nnmh: Receiving headers...done"))
diff --git a/lisp/gnus/nnml.el b/lisp/gnus/nnml.el
index 8275e19f3b6..c825e097481 100644
--- a/lisp/gnus/nnml.el
+++ b/lisp/gnus/nnml.el
@@ -178,7 +178,7 @@ non-nil.")
                    (> number nnmail-large-newsgroup)
                    (zerop (% count 20))
                    (nnheader-message 6 "nnml: Receiving headers... %d%%"
-                                     (/ (* count 100) number))))
+                                     (floor (* count 100.0) number))))
 
             (and (numberp nnmail-large-newsgroup)
                  (> number nnmail-large-newsgroup)
diff --git a/lisp/gnus/nnspool.el b/lisp/gnus/nnspool.el
index 9e9537af1f9..f10b1ad6c54 100644
--- a/lisp/gnus/nnspool.el
+++ b/lisp/gnus/nnspool.el
@@ -174,7 +174,7 @@ there.")
             (and do-message
                  (zerop (% (incf count) 20))
                  (nnheader-message 5 "nnspool: Receiving headers... %d%%"
-                                   (/ (* count 100) number))))
+                                   (floor (* count 100.0) number))))
 
           (when do-message
             (nnheader-message 5 "nnspool: Receiving headers...done"))
diff --git a/lisp/gnus/nntp.el b/lisp/gnus/nntp.el
index 0891dba0387..b617a1beeb2 100644
--- a/lisp/gnus/nntp.el
+++ b/lisp/gnus/nntp.el
@@ -728,7 +728,7 @@ command whose response triggered the error."
                     (> number nntp-large-newsgroup)
                     (zerop (% received 20))
                     (nnheader-message 6 "NNTP: Receiving headers... %d%%"
-                                      (/ (* received 100) number)))
+                                      (floor (* received 100.0) number)))
                (nntp-accept-response))))
          (and (numberp nntp-large-newsgroup)
               (> number nntp-large-newsgroup)
@@ -965,7 +965,7 @@ command whose response triggered the error."
                   (> number nntp-large-newsgroup)
                   (zerop (% received 20))
                   (nnheader-message 6 "NNTP: Receiving articles... %d%%"
-                                    (/ (* received 100) number)))
+                                    (floor (* received 100.0) number)))
              (nntp-accept-response))))
        (and (numberp nntp-large-newsgroup)
             (> number nntp-large-newsgroup)
diff --git a/lisp/gnus/registry.el b/lisp/gnus/registry.el
index 96a89fca1b7..7bada9f3095 100644
--- a/lisp/gnus/registry.el
+++ b/lisp/gnus/registry.el
@@ -320,7 +320,7 @@ Errors out if the key exists already."
            (when (and (< 0 expected)
                       (= 0 (mod count 1000)))
              (message "reindexing: %d of %d (%.2f%%)"
-                      count expected (/ (* 100 count) expected)))
+                      count expected (/ (* 100.0 count) expected)))
            (dolist (val (cdr-safe (assq tr v)))
              (let* ((value-keys (registry-lookup-secondary-value db tr val)))
                (push key value-keys)
diff --git a/lisp/imenu.el b/lisp/imenu.el
index 65c52828c47..3a856b88397 100644
--- a/lisp/imenu.el
+++ b/lisp/imenu.el
@@ -499,10 +499,7 @@ If REVERSE is non-nil then the beginning is 100 and the end is 0."
   (let ((pos (point))
         (total (buffer-size)))
     (and reverse (setq pos (- total pos)))
-    (if (> total 50000)
-        ;; Avoid overflow from multiplying by 100!
-        (/ (1- pos) (max (/ total 100) 1))
-      (/ (* 100 (1- pos)) (max total 1)))))
+    (floor (* 100.0 (1- pos)) (max total 1))))
 
 (defun imenu--split (list n)
   "Split LIST into sublists of max length N.
diff --git a/lisp/international/ja-dic-cnv.el b/lisp/international/ja-dic-cnv.el
index edb6d8900e6..d9c77bf5652 100644
--- a/lisp/international/ja-dic-cnv.el
+++ b/lisp/international/ja-dic-cnv.el
@@ -280,7 +280,7 @@
                 (cons (cons kana candidates) skkdic-okuri-nasi-entries)
                 skkdic-okuri-nasi-entries-count
                 (1+ skkdic-okuri-nasi-entries-count))
-          (setq ratio (floor (/ (* (point) 100.0) (point-max))))
+          (setq ratio (floor (* (point) 100.0) (point-max)))
           (if (/= (/ prev-ratio 10) (/ ratio 10))
               (progn
                 (message "collected %2d%% ..." ratio)
@@ -306,7 +306,7 @@
       (while l
         (let ((kana (car (car l)))
               (candidates (cdr (car l))))
-          (setq ratio (/ (* count 100) skkdic-okuri-nasi-entries-count)
+          (setq ratio (floor (* count 100.0) skkdic-okuri-nasi-entries-count)
                 count (1+ count))
           (if (/= (/ prev-ratio 10) (/ ratio 10))
               (progn
diff --git a/lisp/net/ange-ftp.el b/lisp/net/ange-ftp.el
index 1f893a72f8e..0685bac26c7 100644
--- a/lisp/net/ange-ftp.el
+++ b/lisp/net/ange-ftp.el
@@ -1613,7 +1613,7 @@ good, skip, fatal, or unknown."
                           -6)))
          (if (zerop ange-ftp-xfer-size)
              (ange-ftp-message "%s...%dk" ange-ftp-process-msg kbytes)
-           (let ((percent (/ (* 100 kbytes) ange-ftp-xfer-size)))
+           (let ((percent (floor (* 100.0 kbytes) ange-ftp-xfer-size)))
              ;; cut out the redisplay of identical %-age messages.
              (unless (eq percent ange-ftp-last-percent)
                (setq ange-ftp-last-percent percent)
diff --git a/lisp/nxml/rng-valid.el b/lisp/nxml/rng-valid.el
index 2bf8f1dfa63..61a96545a82 100644
--- a/lisp/nxml/rng-valid.el
+++ b/lisp/nxml/rng-valid.el
@@ -345,17 +345,11 @@ The schema is set like `rng-auto-set-schema'."
 
 (defun rng-compute-mode-line-string ()
   (cond (rng-validate-timer
-         (concat " Validated:"
-                 (number-to-string
-                  ;; Use floor rather than round because we want
-                  ;; to show 99% rather than 100% for changes near
-                  ;; the end.
-                  (floor (if (eq (buffer-size) 0)
-                             0.0
-                           (/ (* (- rng-validate-up-to-date-end (point-min))
-                                 100.0)
-                              (- (point-max) (point-min))))))
-                 "%%"))
+         (format " Validated:%d%%"
+                 (if (= 0 (buffer-size))
+                     0
+                   (floor (- rng-validate-up-to-date-end (point-min))
+                          (- (point-max) (point-min))))))
         ((> rng-error-count 0)
          (concat " "
                  (propertize "Invalid"
diff --git a/lisp/org/org-colview.el b/lisp/org/org-colview.el
index e14849f68e4..e938ab4ae4b 100644
--- a/lisp/org/org-colview.el
+++ b/lisp/org/org-colview.el
@@ -1086,7 +1086,7 @@ display, or in the #+COLUMNS line of the current buffer."
 (defun org-nofm-to-completion (n m &optional percent)
   (if (not percent)
       (format "[%d/%d]" n m)
-    (format "[%d%%]"(floor (+ 0.5 (* 100. (/ (* 1.0 n) m)))))))
+    (format "[%d%%]" (round (* 100.0 n) m))))
 
 
 (defun org-columns-string-to-number (s fmt)
diff --git a/lisp/org/org-list.el b/lisp/org/org-list.el
index 73f24ce7bd8..432e4310fae 100644
--- a/lisp/org/org-list.el
+++ b/lisp/org/org-list.el
@@ -2555,8 +2555,8 @@ With optional prefix argument ALL, do this for the whole buffer."
                      (checked (car (nth 3 cookie)))
                      (total (cdr (nth 3 cookie)))
                      (new (if percentp
-                              (format "[%d%%]" (/ (* 100 checked)
-                                                  (max 1 total)))
+                              (format "[%d%%]" (floor (* 100.0 checked)
+                                                      (max 1 total)))
                             (format "[%d/%d]" checked total))))
                 (goto-char beg)
                 (insert new)
diff --git a/lisp/org/org.el b/lisp/org/org.el
index e9dae191b99..b545f9ee1cb 100644
--- a/lisp/org/org.el
+++ b/lisp/org/org.el
@@ -4346,7 +4346,8 @@ If TABLE-TYPE is non-nil, also check for table.el-type tables."
       (goto-char (point-min))
       (while (re-search-forward org-table-any-line-regexp nil t)
         (unless quietly
-          (message "Mapping tables: %d%%" (/ (* 100.0 (point)) (buffer-size))))
+          (message "Mapping tables: %d%%"
+                   (floor (* 100.0 (point)) (buffer-size))))
         (beginning-of-line 1)
         (when (and (looking-at org-table-line-regexp)
                    ;; Exclude tables in src/example/verbatim/clocktable blocks
@@ -12679,7 +12680,8 @@ statistics everywhere."
                 (outline-next-heading)))
             (setq new
                   (if is-percent
-                      (format "[%d%%]" (/ (* 100 cnt-done) (max 1 cnt-all)))
+                      (format "[%d%%]" (floor (* 100.0 cnt-done)
+                                              (max 1 cnt-all)))
                     (format "[%d/%d]" cnt-done cnt-all))
                   ndel (- (match-end 0) checkbox-beg))
             ;; handle overlays when updating cookie from column view
diff --git a/lisp/play/decipher.el b/lisp/play/decipher.el
index f42ae90f3c8..c2268a9b057 100644
--- a/lisp/play/decipher.el
+++ b/lisp/play/decipher.el
@@ -793,7 +793,7 @@ TOTAL is the total number of letters in the ciphertext."
         (insert (caar temp-list)
                 (format "%4d%3d%%  "
                         (cl-cadar temp-list)
-                        (/ (* 100 (cl-cadar temp-list)) total)))
+                        (floor (* 100.0 (cl-cadar temp-list)) total)))
         (setq temp-list (nthcdr 4 temp-list)))
       (insert ?\n)
       (setq freq-list (cdr freq-list)
@@ -957,7 +957,7 @@ Creates the statistics buffer if it doesn't exist."
                     ": A B C D E F G H I J K L M N O P Q R S T U V W X Y Z *"
                     (format "%4d %4d %3d%%\n  "
                             (cl-third entry) (cl-second entry)
-                            (/ (* 100 (cl-second entry)) total-chars))
+                            (floor (* 100.0 (cl-second entry)) total-chars))
                     (decipher--digram-counts (aref decipher--after  i)) ?\n))))
       (setq buffer-read-only t)
       (set-buffer-modified-p nil)
diff --git a/lisp/profiler.el b/lisp/profiler.el
index 2425d8c56a7..f28bbfe2768 100644
--- a/lisp/profiler.el
+++ b/lisp/profiler.el
@@ -56,7 +56,7 @@
          (format "%s" object))))
 
 (defun profiler-format-percent (number divisor)
-  (concat (number-to-string (/ (* number 100) divisor)) "%"))
+  (format "%d%%" (floor (* 100.0 number) divisor)))
 
 (defun profiler-format-number (number)
   "Format NUMBER in human readable string."
diff --git a/lisp/progmodes/cc-cmds.el b/lisp/progmodes/cc-cmds.el
index 94dc34bb20e..c9f59451b7e 100644
--- a/lisp/progmodes/cc-cmds.el
+++ b/lisp/progmodes/cc-cmds.el
@@ -1809,7 +1809,7 @@ with a brace block."
   (c-save-buffer-state
       (beginning-of-defun-function end-of-defun-function
        where pos name-end case-fold-search)
- 
+
     (save-restriction
       (widen)
       (save-excursion
@@ -3412,7 +3412,7 @@ Otherwise reindent just the current line."
       (if (< c-progress-interval (- now lastsecs))
           (progn
             (message "Indenting region... (%d%% complete)"
-                     (/ (* 100 (- (point) start)) (- end start)))
+                     (floor (* 100.0 (- (point) start)) (- end start)))
             (aset c-progress-info 2 now)))
       )))
 
diff --git a/lisp/progmodes/cpp.el b/lisp/progmodes/cpp.el
index bf8458e725a..0a51add68b6 100644
--- a/lisp/progmodes/cpp.el
+++ b/lisp/progmodes/cpp.el
@@ -234,7 +234,8 @@ A prefix arg suppresses display of that buffer."
       (cpp-progress-message "Parsing...")
       (while (re-search-forward cpp-parse-regexp nil t)
         (cpp-progress-message "Parsing...%d%%"
-                          (/ (* 100 (- (point) (point-min))) (buffer-size)))
+                              (floor (* 100.0 (- (point) (point-min)))
+                                     (buffer-size)))
         (let ((match (buffer-substring (match-beginning 0) (match-end 0))))
           (cond ((or (string-equal match "'")
                      (string-equal match "\""))
diff --git a/lisp/progmodes/idlwave.el b/lisp/progmodes/idlwave.el
index 8e30aa29502..d7594428e8d 100644
--- a/lisp/progmodes/idlwave.el
+++ b/lisp/progmodes/idlwave.el
@@ -4881,7 +4881,7 @@ Cache to disk for quick recovery."
               props (car (cdr elem)))
         (if (= (mod elem-cnt msg-cnt) 0)
             (message "Converting XML routine info...%2d%%"
-                     (/ (* elem-cnt 100) nelem)))
+                     (floor (* elem-cnt 100.0) nelem)))
         (cond
          ((eq type 'ROUTINE)
           (if (setq alias (assq 'alias_to props))
@@ -8694,7 +8694,7 @@ can be used to detect possible name clashes during this process."
       (erase-buffer)
       (while (setq routine (pop routines))
         (if (= (mod (setq n (1+ n)) step) 0)
-            (message "Compiling list...(%2d%%)" (/ (* n 100) nroutines)))
+            (message "Compiling list...(%2d%%)" (floor (* n 100.0) nroutines)))
 
         ;; Get a list of all twins
         (setq twins (idlwave-routine-twins routine (or lroutines routines)))
diff --git a/lisp/progmodes/opascal.el b/lisp/progmodes/opascal.el
index 2eba620ceb2..ef3433f003b 100644
--- a/lisp/progmodes/opascal.el
+++ b/lisp/progmodes/opascal.el
@@ -368,7 +368,7 @@ routine.")
          ;; Report the percentage complete.
          (setq opascal-progress-last-reported-point p)
          (message "%s %s ... %d%%"
-                  desc (buffer-name) (/ (* 100 p) (point-max))))))
+                  desc (buffer-name) (floor (* 100.0 p) (point-max))))))
 
 (defun opascal-next-line-start (&optional from-point)
   ;; Returns the first point of the next line.
diff --git a/lisp/progmodes/vhdl-mode.el b/lisp/progmodes/vhdl-mode.el
index 5ed0ff0ebed..16e4e8ed53d 100644
--- a/lisp/progmodes/vhdl-mode.el
+++ b/lisp/progmodes/vhdl-mode.el
@@ -7383,11 +7383,11 @@ only-lines."
                 (- (nth 1 (current-time)) (aref vhdl-progress-info 2))))
     (let ((delta (- (aref vhdl-progress-info 1)
                     (aref vhdl-progress-info 0))))
-      (if (= 0 delta)
-          (message (concat string "... (100%s)") "%")
-        (message (concat string "... (%2d%s)")
-                 (/ (* 100 (- pos (aref vhdl-progress-info 0)))
-                    delta) "%")))
+      (message "%s... (%2d%%)" string
+               (if (= 0 delta)
+                   100
+                 (floor (* 100.0 (- pos (aref vhdl-progress-info 0)))
+                        delta))))
     (aset vhdl-progress-info 2 (nth 1 (current-time)))))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -13881,10 +13881,10 @@ hierarchy otherwise.")
       ;; do for all files
       (while file-list
         (unless noninteractive
-          (message "Scanning %s %s\"%s\"... (%2d%s)"
+          (message "Scanning %s %s\"%s\"... (%2d%%)"
                    (if is-directory "directory" "files")
                    (or num-string "") name
-                   (/ (* 100 (- no-files (length file-list))) no-files) "%"))
+                   (floor (* 100.0 (- no-files (length file-list))) no-files)))
         (let ((file-name (abbreviate-file-name (car file-list)))
               ent-list arch-list arch-ent-list conf-list
               pack-list pack-body-list inst-list inst-ent-list)
diff --git a/lisp/ps-print.el b/lisp/ps-print.el
index e76b332ee3c..0ba470be68c 100644
--- a/lisp/ps-print.el
+++ b/lisp/ps-print.el
@@ -6043,10 +6043,7 @@ XSTART YSTART are the relative position for the first page in a sheet.")
             (progn
               (setq ps-razchunk q-done)
               (message "Formatting...%3d%%"
-                       (if (< q-todo 100)
-                           (/ (* 100 q-done) q-todo)
-                         (/ q-done (/ q-todo 100)))
-                       ))))))
+                       (floor (* 100.0 q-done) q-todo)))))))
 
 (defvar ps-last-font nil)
 
diff --git a/lisp/simple.el b/lisp/simple.el
index 7eed279ed59..1a4bcf124db 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1255,10 +1255,7 @@ in *Help* buffer.  See also the command `describe-char'."
          (end (point-max))
          (pos (point))
          (total (buffer-size))
-         (percent (if (> total 50000)
-                      ;; Avoid overflow from multiplying by 100!
-                      (/ (+ (/ total 200) (1- pos)) (max (/ total 100) 1))
-                    (/ (+ (/ total 2) (* 100 (1- pos))) (max total 1))))
+         (percent (round (* 100.0 (1- pos)) (max 1 total)))
          (hscroll (if (= (window-hscroll) 0)
                       ""
                     (format " Hscroll=%d" (window-hscroll))))
diff --git a/lisp/textmodes/bibtex.el b/lisp/textmodes/bibtex.el
index 9d6d19e6e1e..b1232d4c0a0 100644
--- a/lisp/textmodes/bibtex.el
+++ b/lisp/textmodes/bibtex.el
@@ -2099,7 +2099,7 @@ If FLAG is nil, a message is echoed if point was incremented at least
          (let* ((size (- (point-max) (point-min)))
                 (perc (if (= size 0)
                           100
-                        (/ (* 100 (- (point) (point-min))) size))))
+                        (floor (* 100.0 (- (point) (point-min))) size))))
            (when (>= perc (+ bibtex-progress-lastperc
                              bibtex-progress-interval))
              (setq bibtex-progress-lastperc perc)
diff --git a/lisp/textmodes/flyspell.el b/lisp/textmodes/flyspell.el
index e0749180611..64aa3de146e 100644
--- a/lisp/textmodes/flyspell.el
+++ b/lisp/textmodes/flyspell.el
@@ -1350,7 +1350,7 @@ that may be included as part of a word (see `ispell-dictionary-alist')."
         (if (and flyspell-issue-message-flag (= count 100))
             (progn
               (message "Spell Checking...%d%%"
-                       (* 100 (/ (float (- (point) beg)) (- end beg))))
+                       (floor (* 100.0 (- (point) beg)) (- end beg)))
               (setq count 0))
           (setq count (+ 1 count)))
         (flyspell-word)
@@ -1403,7 +1403,7 @@ The buffer to mark them in is `flyspell-large-region-buffer'."
           ;; be unnecessary too. -- rms.
           (if flyspell-issue-message-flag
               (message "Spell Checking...%d%% [%s]"
-                       (* 100 (/ (float (point)) (point-max)))
+                       (floor (* 100.0 (point)) (point-max))
                        word))
           (with-current-buffer flyspell-large-region-buffer
             (goto-char buffer-scan-pos)
diff --git a/lisp/textmodes/table.el b/lisp/textmodes/table.el
index edc78e52efa..fa9f0fa638a 100644
--- a/lisp/textmodes/table.el
+++ b/lisp/textmodes/table.el
@@ -1893,7 +1893,9 @@ all the table specific features."
             (while (and (re-search-forward border3 (point-max) t)
                         (not (and (input-pending-p)
                                   table-abort-recognition-when-input-pending)))
-              (message "Recognizing tables...(%d%%)" (/ (* 100 (match-beginning 0)) (- (point-max) (point-min))))
+              (message "Recognizing tables...(%d%%)"
+                       (floor (* 100.0 (match-beginning 0))
+                              (- (point-max) (point-min))))
               (let ((beg (match-beginning 0))
                     end)
                 (if (re-search-forward non-border (point-max) t)