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From: "raphael.monod at wanadoo dot fr" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/107373] New: Unexpected result with loop optimisation
Date: Mon, 24 Oct 2022 08:39:15 +0000	[thread overview]
Message-ID: <bug-107373-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107373

            Bug ID: 107373
           Summary: Unexpected result with loop optimisation
           Product: gcc
           Version: 8.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: raphael.monod at wanadoo dot fr
  Target Milestone: ---

Created attachment 53765
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53765&action=edit
Source of test producing the bug (MWE)

The attached test show the vector "tab_int_from_logical" contains -1, although
+1 are expected.

Compiler option -O3 is required to get this bug.
Adding a print in the loop go around it.
Degreasing the dimension 'IDIM' from 16 to 15 go around it.

I do not have test all GCC releases, but I met this bug with release : 7.3.0,
8.2.0, 8.5.0, 9.4.0.

Everything is good with releases 6.3.0, 11.3.0, 12.1.0

I known that releases used to produce this bug are no longer supported, bug I
think that debian 10 (which is again supported) use 8.x GCC release.

             reply	other threads:[~2022-10-24  8:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-24  8:39 raphael.monod at wanadoo dot fr [this message]
2022-10-24 12:25 ` [Bug fortran/107373] " marxin at gcc dot gnu.org
2022-10-24 12:26 ` marxin at gcc dot gnu.org
2022-10-24 12:40 ` jb at gcc dot gnu.org
2022-10-24 13:06 ` marxin at gcc dot gnu.org
2022-10-24 13:25 ` rguenth at gcc dot gnu.org

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