Remove no-longer-needed integer overflow code

* lisp/calculator.el (calculator-number-to-string):
Use truncate, not calculator-truncate, since integer
overflow cannot occur here.
* lisp/calendar/cal-persia.el (calendar-persian-year-from-absolute):
* lisp/gnus/gnus-agent.el (gnus-agent-read-article-number):
* lisp/gnus/nnmaildir.el (nnmaildir--group-maxnum)
(nnmaildir--new-number):
* lisp/scroll-bar.el (scroll-bar-scale):
* lisp/simple.el (beginning-of-buffer, end-of-buffer):
Simplify, now that integer overflow cannot occur.

2 files changed, 2 insertions, 19 deletions

diff --git a/lisp/gnus/gnus-agent.el b/lisp/gnus/gnus-agent.el
index a09b4368893..40d0d246056 100644
--- a/lisp/gnus/gnus-agent.el
+++ b/lisp/gnus/gnus-agent.el
@@ -1909,21 +1909,8 @@ article numbers will be returned."
 (defsubst gnus-agent-read-article-number ()
   "Reads the article number at point.  Returns nil when a valid article number can not be read."
 
-  ;; It is unfortunate but the read function quietly overflows
-  ;; integer.  As a result, I have to use string operations to test
-  ;; for overflow BEFORE calling read.
   (when (looking-at "[0-9]+\t")
-    (let ((len (- (match-end 0) (match-beginning 0))))
-      (cond ((< len 9)
-             (read (current-buffer)))
-            ((= len 9)
-             ;; Many 9 digit base-10 numbers can be represented in a 27-bit int
-             ;; Back convert from int to string to ensure that this is one of them.
-             (let* ((str1 (buffer-substring (match-beginning 0) (1- (match-end 0))))
-                    (num (read (current-buffer)))
-                    (str2 (int-to-string num)))
-               (when (equal str1 str2)
-                 num)))))))
+    (read (current-buffer))))
 
 (defsubst gnus-agent-copy-nov-line (article)
   "Copy the indicated ARTICLE from the overview buffer to the nntp server buffer."
diff --git a/lisp/gnus/nnmaildir.el b/lisp/gnus/nnmaildir.el
index 3becee35112..246f52c8d2b 100644
--- a/lisp/gnus/nnmaildir.el
+++ b/lisp/gnus/nnmaildir.el
@@ -322,8 +322,6 @@ This variable is set by `nnmaildir-request-article'.")
         (setq ino-opened (file-attribute-inode-number attr)
               nlink (file-attribute-link-number attr)
               number-linked (+ number-opened nlink))
-        (if (or (< nlink 1) (< number-linked nlink))
-            (signal 'error '("Arithmetic overflow")))
         (setq attr (file-attributes
                     (concat dir (number-to-string number-linked))))
         (or attr (throw 'return (1- number-linked)))
@@ -395,9 +393,7 @@ This variable is set by `nnmaildir-request-article'.")
         (let* ((attr (file-attributes path-open))
                (nlink (file-attribute-link-number attr)))
           (setq ino-open (file-attribute-inode-number attr)
-                number-link (+ number-open nlink))
-          (if (or (< nlink 1) (< number-link nlink))
-              (signal 'error '("Arithmetic overflow"))))
+                number-link (+ number-open nlink)))
         (if (= number-link previous-number-link)
             ;; We've already tried this number, in the previous loop iteration,
             ;; and failed.