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.

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))))