[Bug fortran/121683] Data corruption with sourced allocation from constructor

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121683

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Paul Thomas <[email protected]>:

https://gcc.gnu.org/g:ad78f61449bc9ef1d585e69ff48c46574f9a9382

commit r17-3385-gad78f61449bc9ef1d585e69ff48c46574f9a9382
Author: Paul Thomas <[email protected]>
Date:   Thu Aug 13 16:00:15 2026 +0100

    ortran: Fix data corruption with allocation from ctr source [P121683]

    2026-08-13  Paul Thomas  <[email protected]>

    gcc/fortran
            PR fortran/121683
            * trans-expr.cc (gfc_trans_subcomponent_assign): For derived
            type expressions assigned to a class or derived type component
            copy allocatable components if necessary. Likewise, for a class
            expression assigned to a scalar class component, allocate the
            component and use the vptr copy.

    gcc/testsuite/
            PR fortran/121683
            * gfortran.dg/structure_constructor_18.f90: New test