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From: "evouga at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/43529]  New: G++ doesn't optimize away empty loop when index is a double
Date: Thu, 25 Mar 2010 23:42:00 -0000	[thread overview]
Message-ID: <bug-43529-18958@http.gcc.gnu.org/bugzilla/> (raw)

Empty loops where the loop index is an integer are optimized away, but the
following loop is not (presumably because it is more difficult to prove that it
terminates in finite time?)

int main()
{
        for(double i=0; i<1e9; i+=1);
}

Command line: g++ -O3


-- 
           Summary: G++ doesn't optimize away empty loop when index is a
                    double
           Product: gcc
           Version: 4.4.1
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: evouga at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43529


             reply	other threads:[~2010-03-25 23:42 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-25 23:42 evouga at gmail dot com [this message]
2010-03-26 11:46 ` [Bug tree-optimization/43529] " rguenth at gcc dot gnu dot org
2010-06-04 23:15 ` changpeng dot fang at amd dot com
2010-06-04 23:29 ` changpeng dot fang at amd dot com
2010-06-05  0:05 ` pinskia at gcc dot gnu dot org
2010-06-05 10:40 ` rguenth at gcc dot gnu dot org

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