Bug 51970

(In reply to comment #0)
> The code is accepted by trunk r183357.

And it crashes in the same way with 4.7.0 2012-01-18 trunk revision 183273.

(In any case it is not a (real) regression as GCC 4.6 didn't support polymorphic arrays.)

> And it crashes in the same way with 4.7.0 2012-01-18 trunk revision 183273.

So marked as NEW.

Created attachment 26443 [details]
Draft patch for trans-intrinsic.c

There are two issues:

a) from_expr->rank *and* to_expr->rank are 0 instead of 1.
   That's a variant of the issue of PR 51977.

b) trans-intrinsic.c's conv_move_alloc does not properly handle polymorphic
   arrays.

For (b) a draft patch is attached. TODO: Regtest it, try combinations of TYPE and CLASS, try CLASS with allocatable components - and CLASS components.


To use it, you need to either fix issue (a) or you can try the following hack:

--- a/gcc/fortran/check.c
+++ b/gcc/fortran/check.c
@@ -2726,0 +2727,5 @@ gfc_check_move_alloc (gfc_expr *from, gfc_expr *to)
+  /* THIS IS A HACK! */
+  if (from->ts.type == BT_CLASS && CLASS_DATA (from)->attr.dimension)
+    from->rank = CLASS_DATA (from)->as->rank;
+  if (to->ts.type == BT_CLASS && CLASS_DATA (to)->attr.dimension)
+    to->rank = CLASS_DATA (to)->as->rank;

The patch attached to comment #4 + the "hack" let the test compile without error (although I don't know if it is valid). I have noticed the following changes:

For 51948, before the patch I had two errors

[macbook] f90/bug% gfc pr51948.f90
pr51948.f90:14.24:

    call move_alloc (x, func)
                        1
Error: 'to' argument of 'move_alloc' intrinsic at (1) must be a variable
pr51948.f90:7.24:

    call move_alloc (x, func)
                        1
Error: the 'from' and 'to' arguments of 'move_alloc' intrinsic at (1) must have the same rank 0/1

After the patch I have only one

[macbook] f90/bug% gfc pr51948.f90
pr51948.f90:14.24:

    call move_alloc (x, func)
                        1
Error: 'to' argument of 'move_alloc' intrinsic at (1) must be a variable

For another avatar and the test in pr51977, the error is replaced by an ICE: before the patch

[macbook] f90/bug% gfc pr51948_db_1.f90
pr51948_db_1.f90:7.24:

    call move_alloc (x, func)
                        1
Error: the 'from' and 'to' arguments of 'move_alloc' intrinsic at (1) must have the same rank 0/1

after the patch

[macbook] f90/bug% gfc pr51948_db_1.f90
pr51948_db_1.f90: In function 'func':
pr51948_db_1.f90:9:0: internal compiler error: in fold_convert_loc, at fold-const.c:2016

Author: burnus
Date: Fri Jan 27 13:08:52 2012
New Revision: 183622

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=183622
Log:
2012-01-27  Tobias Burnus  <burnus@net-b.de>

        PR fortran/51970
        PR fortran/51977
        * primary.c (gfc_match_varspec. gfc_match_rvalue): Set
        handle array spec for BT_CLASS.
        * expr.c (gfc_get_variable_expr, gfc_lval_expr_from_sym)
        * frontend-passes.c (create_var): Ditto.
        * resolve.c (resolve_actual_arglist, resolve_assoc_var): Ditto.
        * trans-decl.c (gfc_trans_deferred_vars): Use class_pointer
        instead of attr.pointer.
        (gfc_generate_function_code): Use CLASS_DATA (sym) for BT_CLASS.
        * trans-intrinsic.c (conv_intrinsic_move_alloc): Move assert.
        * trans-stmt.c (trans_associate_var): Ask for the descriptor.

2012-01-27  Tobias Burnus  <burnus@net-b.de>

        PR fortran/51970
        PR fortran/51977
        * gfortran.dg/move_alloc_13.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/move_alloc_13.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/expr.c
    trunk/gcc/fortran/frontend-passes.c
    trunk/gcc/fortran/primary.c
    trunk/gcc/fortran/resolve.c
    trunk/gcc/fortran/trans-decl.c
    trunk/gcc/fortran/trans-intrinsic.c
    trunk/gcc/fortran/trans-stmt.c
    trunk/gcc/testsuite/ChangeLog

FIXED on the trunk (4.7).