[Bug fortran/106546] Incorrect reuse of allocatable array temporaries under -O2 -fno-automatic

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106546

--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Thomas Koenig <tkoe...@gcc.gnu.org>:

https://gcc.gnu.org/g:996673496e9cbc05b6ec55f0ab1324c3ffe4a876

commit r17-631-g996673496e9cbc05b6ec55f0ab1324c3ffe4a876
Author: Thomas Koenig <tkoe...@gcc.gnu.org>
Date:   Wed May 20 22:43:10 2026 +0200

    PR fortran/106546 - inline matmul with -fno-automatic

    There was a problem caused with allocatable arrays used for
    front-end optimization when -fno-automatic was specified.
    Solved by explicitly setting the automatic attribute on the
    symbol.  It required "-O2 -fcheck=bounds -fno-automatic"
    to be seen.

    gcc/fortran/ChangeLog:

            PR fortran/106546
            * frontend-passes.cc (create_var): Set attr->automatic on
            new symbol.
            (create_do_loop): Likewise on iteration variable.

    gcc/testsuite/ChangeLog:

            PR fortran/106546
            * gfortran.dg/inline_matmul_27.f90: New test.