[Bug debug/103315] Gfortran DW_AT_Rank expression not emitting correct rank value.

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103315

--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:7230ae73c96dc7d19f072627e1f9c48e008e03b8

commit r11-9336-g7230ae73c96dc7d19f072627e1f9c48e008e03b8
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sun Nov 21 21:08:04 2021 +0100

    fortran, debug: Fix up DW_AT_rank [PR103315]

    For DW_AT_rank we were emitting
            .uleb128 0x4    # DW_AT_rank
            .byte   0x97    # DW_OP_push_object_address
            .byte   0x23    # DW_OP_plus_uconst
            .uleb128 0x1c
            .byte   0x6     # DW_OP_deref
    on 64-bit and
            .uleb128 0x4    # DW_AT_rank
            .byte   0x97    # DW_OP_push_object_address
            .byte   0x23    # DW_OP_plus_uconst
            .uleb128 0x10
            .byte   0x6     # DW_OP_deref
    on 32-bit.  I think this is wrong, as dtype.rank field in the descriptor
    has unsigned char type, not pointer type nor pointer sized integral.
    E.g. if we have a
        REAL :: a(..)
    dummy argument, which is passed as a reference to the function descriptor,
    we want to evaluate a->dtype.rank.  The above DWARF expressions perform
    *(uintptr_t *)(a + 0x1c)
    and
    *(uintptr_t *)(a + 0x10)
    respectively.  The following patch changes those to:
            .uleb128 0x5    # DW_AT_rank
            .byte   0x97    # DW_OP_push_object_address
            .byte   0x23    # DW_OP_plus_uconst
            .uleb128 0x1c
            .byte   0x94    # DW_OP_deref_size
            .byte   0x1
    and
            .uleb128 0x5    # DW_AT_rank
            .byte   0x97    # DW_OP_push_object_address
            .byte   0x23    # DW_OP_plus_uconst
            .uleb128 0x10
            .byte   0x94    # DW_OP_deref_size
            .byte   0x1
    which perform
    *(unsigned char *)(a + 0x1c)
    and
    *(unsigned char *)(a + 0x10)
    respectively.

    2021-11-21  Jakub Jelinek  <jakub@redhat.com>

            PR debug/103315
            * trans-types.c (gfc_get_array_descr_info): Use DW_OP_deref_size 1
            instead of DW_OP_deref for DW_AT_rank.

    (cherry picked from commit da17c304e22ba256eba0b03710aa329115163b08)