Add support for DW_AT_GNAT_descriptive_type.
* gdbtypes.h (enum type_specific_kind): New enum.
(struct main_type) [type_specific_field]: New component.
[type_specific]: Add new component "gnat_stuff".
(struct gnat_aux_type): New type.
(INIT_CPLUS_SPECIFIC): Also set TYPE_SPECIFIC_FIELD (type).
(HAVE_CPLUS_STRUCT): Also check TYPE_SPECIFIC_FIELD (type).
(gnat_aux_default, allocate_gnat_aux_type): Add declaration.
(INIT_GNAT_SPECIFIC, ALLOCATE_GNAT_AUX_TYPE, HAVE_GNAT_AUX_INFO)
(TYPE_SPECIFIC_FIELD): New macros.
(TYPE_CPLUS_SPECIFIC): Return cplus_struct_default if the given
type does not hold any cplus-specific data.
(TYPE_RAW_CPLUS_SPECIFIC): New macro.
(TYPE_GNAT_SPECIFIC, TYPE_DESCRIPTIVE_TYPE): New macros.
(TYPE_IS_OPAQUE): Use HAVE_CPLUS_STRUCT to check if type has
cplus-specific data.
* gdbtypes.c (allocate_cplus_struct_type): Minor stylistic rewrite.
Set new component TYPE_SPECIFIC_FIELD (type).
(gnat_aux_default): New constant.
(allocate_gnat_aux_type): New function.
(init_type): Add initialization the type-specific stuff for
TYPE_CODE_FLT and TYPE_CODE_FUNC types.
(print_gnat_stuff): New function.
(recursive_dump_type): Use HAVE_CPLUS_STRUCT to check for cplus-
specific data. Adjust code that prints the contents of the
type-specific union using the TYPE_SPECIFIC_FIELD value.
* dwarf2read.c (dwarf2_attach_fields_to_type): Do not allocate
the type cplus stuff for Ada types.
(dwarf2_add_member_fn, dwarf2_attach_fn_fields_to_type):
Error out if these routines are called with an Ada type.
(read_structure_type, read_array_type, read_subrange_type):
Add call to set_descriptive_type.
(set_die_type): Initialize the gnat-specific data if necessary.
(need_gnat_info, die_descriptive_type, set_descriptive_type):
New functions.
* ada-lang.c (decode_constrained_packed_array_type): Use
decode_constrained_packed_array_type instead of doing a standard
lookup to locate a parallel type.
(find_parallel_type_by_descriptive_type): New function.
(ada_find_parallel_type_with_name): New function.
(ada_find_parallel_type): Reimplement using
ada_find_parallel_type_with_name.
* ada-valprint.c (print_field_values): Use HAVE_CPLUS_STRUCT
to check if type has a cplus stuff.
* linespec.c (total_number_of_methods): Likewise.
* mdebugread.c (new_type): Likewise.
gdb/testsuite/ChangeLog:
* gdb.base/maint.exp: Adjust the expected output for the
"maint print type" test. Use gdb_test_multiple instead of
gdb_sent/gdb_expect.