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minor doc fix for INT_MIN % -1


From: Paul Eggert
Subject: minor doc fix for INT_MIN % -1
Date: Mon, 05 Jun 2006 19:29:21 -0700
User-agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.4 (gnu/linux)

I installed this:

2006-06-05  Paul Eggert  <address@hidden>

        * doc/autoconf.texi (Integer Overflow): Mention that INT_MIN % -1
        typically overflows on x86 CPUs, even though the C standard
        requires otherwise.

--- doc/autoconf.texi   5 Jun 2006 08:39:57 -0000       1.1040
+++ doc/autoconf.texi   6 Jun 2006 01:44:53 -0000       1.1041
@@ -14479,7 +14479,10 @@ to an integer type or store it into an i
 are portable to the vast majority of modern platforms.  However, signed
 integer division is not always harmless: for example, on CPUs of the
 i386 family, dividing @code{INT_MIN} by @code{-1} yields a SIGFPE signal
-which by default terminates the program.
+which by default terminates the program.  Worse, taking the remainder
+of these two values typically yields the same signal on these CPUs,
+even though the C standard requires @code{INT_MIN % -1} to yield zero
+because the expression does not overflow.
 
 GCC users might consider using the
 @option{-ftrapv} option if they are worried about porting their code to




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