https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83118
--- Comment #42 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-9 branch has been updated by Paul Thomas <pa...@gcc.gnu.org>: https://gcc.gnu.org/g:e780e940a9f53b93bdf6bd70fdb3ec2b287a52e3 commit r9-9158-ge780e940a9f53b93bdf6bd70fdb3ec2b287a52e3 Author: Paul Thomas <pa...@gcc.gnu.org> Date: Fri Dec 18 14:00:11 2020 +0000 As well as the PR this patch fixes problems in handling class objects 2020-12-18 Paul Thomas <pa...@gcc.gnu.org> gcc/fortran PR fortran/83118 PR fortran/96012 * resolve.c (resolve_ordinary_assign): Generate a vtable if necessary for scalar non-polymorphic rhs's to unlimited lhs's. * trans-array.c (get_class_info_from_ss): New function. (gfc_trans_allocate_array_storage): Defer obtaining class element type until all sources of class exprs are tried. Use class API rather than TREE_OPERAND. Look for class expressions in ss->info by calling get_class_info_from_ss. After, obtain the element size for class descriptors. Where the element type is unknown, cast the data as character(len=size) to overcome unlimited polymorphic problems. (gfc_conv_ss_descriptor): Do not fix class variable refs. (build_class_array_ref, structure_alloc_comps): Replace code replicating the new function gfc_resize_class_size_with_len. (gfc_alloc_allocatable_for_assignment): Obtain element size for lhs in cases of deferred characters and class enitities. Move code for the element size of rhs to start of block. Clean up extraction of class parameters throughout this function. After the shape check test whether or not the lhs and rhs element sizes are the same. Use earlier evaluation of 'cond_null'. Reallocation of lhs only to happen if size changes or element size changes. * trans-expr.c (gfc_resize_class_size_with_len): New function. (gfc_get_class_from_expr): If a constant expression is encountered, return NULL_TREE; (trans_scalar_class_assign): New function. (gfc_conv_procedure_call): Ensure the vtable is present for passing a non-class actual to an unlimited formal. (trans_class_vptr_len_assignment): For expressions of type BT_CLASS, extract the class expression if necessary. Use a statement block outside the loop body. Ensure that 'rhs' is of the correct type. Obtain rhs vptr in all circumstances. (gfc_trans_scalar_assign): Call trans_scalar_class_assign to make maximum use of the vptr copy in place of assignment. (trans_class_assignment): Actually do reallocation if needed. (gfc_trans_assignment_1): Simplify some of the logic with 'realloc_flag'. Set 'vptr_copy' for all array assignments to unlimited polymorphic lhs. * trans.c (gfc_build_array_ref): Call gfc_resize_class_size_ with_len to correct span for unlimited polymorphic decls. * trans.h : Add prototype for gfc_resize_class_size_with_len. gcc/testsuite/ PR fortran/83118 PR fortran/96012 * gfortran.dg/dependency_60.f90: New test. * gfortran.dg/class_allocate_25.f90: New test. * gfortran.dg/class_assign_4.f90: New test. * gfortran.dg/unlimited_polymorphic_32.f03: New test. (cherry picked from commit ce8dcc9105cbd4043d575d8b2c91309a423951a9)