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Date: Fri, 22 Sep 2006 19:13:00 -0000
Subject: [Bug c/29186]  New: optimzation breaks floating point exception flag reading
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From: "kreckel at ginac dot de" <gcc-bugzilla@gcc.gnu.org>
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See <http://gcc.gnu.org/ml/gcc-help/2006-09/msg00232.html>.

Disassembling the code suggests that, using gcc-4.1,2, both calls to
fetestexcept(3) mysteriously happened before the division when optimization is
turned on. This was not the case with earlier versions of gcc, where the calls
to fetestexcept(3) bracket the fdivl instruction.


-- 
           Summary: optimzation breaks floating point exception flag reading
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: kreckel at ginac dot de
 GCC build triplet: i486-linux-gnu
  GCC host triplet: i486-linux-gnu
GCC target triplet: i486-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29186