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Date: Thu, 22 Feb 2007 22:39:00 -0000
Subject: [Bug rtl-optimization/30931]  New: Simple test case loops infinitely with -O1 -fstrength-reduce.
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From: "bergner at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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The simple test which I'll attach shortly, loops infinitely when compiled with
-O1 -fstrength-reduce and executes fine with plain -O1.  Doing a little
debugging, it seems the loop index variable "i" is not incremented within the
loop causing us to loop forever.

I have tested this using the latest FSF 4.1, 4.2 and mainline compiler sources
and it only fails using the 4.1 compiler.  Using an older 3.4.6 distro
compiler, it executes fine, so this _looks_ like a regression.


-- 
           Summary: Simple test case loops infinitely with -O1 -fstrength-
                    reduce.
           Product: gcc
           Version: 4.1.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bergner at gcc dot gnu dot org
 GCC build triplet: i686-linux
  GCC host triplet: i686-linux
GCC target triplet: i686-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30931