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From: "anlauf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/107968] array slicing gives wrong result for an array
 pointer defined in a subroutine
Date: Mon, 05 Dec 2022 21:36:21 +0000
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X-Bugzilla-Component: fortran
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107968

--- Comment #2 from anlauf at gcc dot gnu.org ---
The following attempt fixes the erroneous output:

diff --git a/gcc/fortran/trans-io.cc b/gcc/fortran/trans-io.cc
index 9f86815388c..c4525f67ef3 100644
--- a/gcc/fortran/trans-io.cc
+++ b/gcc/fortran/trans-io.cc
@@ -2641,6 +2641,9 @@ gfc_trans_transfer (gfc_code * code)
                    seen_vector =3D true;
                    break;
                  }
+
+             if (!seen_vector && !gfc_is_not_contiguous (expr))
+               goto scalarize;
            }

          if (seen_vector && last_dt =3D=3D READ)

However, this defeats the optimization on array I/O and regresses on

gfortran.dg/implied_do_io_1.f90
gfortran.dg/implied_do_io_4.f90=