From:	Robert Ruehlmann <rr9 AT angband DOT org>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Compiler optimization bug
Date:	12 Dec 1999 14:17:38 GMT
Organization:	The Pits of Angband
Lines:	28
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

I think I've found a bug in the DJGPP compiler (gcc 2.95.2).  When optimized
with -O2 the following small sample program goes into an infinite loop.
Debugging with gdb shows strange behaviour like modifications of the 'size'
variable.

<-- cut here -->
static void bug(int size, int tries)
{
    int i;
    int num = 0;

    while (num < size)
    {
        for (i = 1; i < tries; i++) num++;
    }
}

int main()
{
    bug(5, 10);
    return 0;
}
<-- cut here -->

-- 
Robert Ruehlmann ( rr9 AT angband DOT org )
"Thangorodrim - The Angband Page" : http://thangorodrim.angband.org/
Visit the #angband chat channel at Othernet (irc.othernet.org).

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