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From: "albin at yahoo dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/109344] New: feraiseexcept produces incorrect code when
 optimizations are enabled
Date: Thu, 30 Mar 2023 07:49:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109344

            Bug ID: 109344
           Summary: feraiseexcept produces incorrect code when
                    optimizations are enabled
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: albin at yahoo dot com
  Target Milestone: ---

At -O1, calls to feraiseexcept are inlined. But the inlined code produces
incorrect results.

See here, only the first function behaves as expected:
https://godbolt.org/z/ncc3cjoKh

The behavior persists across many versions.

(A side note, I don't understand how the first function works, in order to
produce a divbyzero exception it appears to divide 0 / 1, not 1 / 0, am I
reading the assembly wrong?)=