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Date: Fri, 09 Jul 2010 10:41:00 -0000
Subject: [Bug middle-end/44885]  New: [4.6 regression] miscompilation of gnat.dg/aliasing3.adb after mem-ref2
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From: "ebotcazou at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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There is a regression in gnat.dg visible on various 32-bit platforms:
  http://gcc.gnu.org/ml/gcc-testresults/2010-07/msg00744.html
  http://gcc.gnu.org/ml/gcc-testresults/2010-07/msg00743.html
  http://gcc.gnu.org/ml/gcc-testresults/2010-07/msg00709.html

The problem is that the new code seems to overlook TYPE_NONALIASED_COMPONENT
when building the MEM_REF and thus gives the wrong alias set to the RTL mem,
causing aliasing memory references to be swapped by the scheduler.


-- 
           Summary: [4.6 regression] miscompilation of gnat.dg/aliasing3.adb
                    after mem-ref2
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ebotcazou at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44885