(append_composite_type_field_aligned): Use the new function.
* gdbtypes.h (append_composite_type_field_raw): Declare.
* target-descriptions.c (struct tdesc_type_field): Add start and end.
(struct tdesc_type_flag): New type.
(struct tdesc_type): Add TDESC_TYPE_STRUCT and TDESC_TYPE_FLAGS to
kind. Add size to u.u. Add u.f for flags.
(tdesc_gdb_type): Handle TDESC_TYPE_STRUCT and TDESC_TYPE_FLAGS.
(tdesc_free_type): Likewise.
(tdesc_create_struct, tdesc_set_struct_size, tdesc_create_flags): New.
(tdesc_add_field): Handle TDESC_TYPE_STRUCT.
(tdesc_add_bitfield, tdesc_add_flag): New.
* target-descriptions.h (tdesc_create_struct, tdesc_set_struct_size)
(tdesc_create_flags, tdesc_add_bitfield, tdesc_add_flag): Declare.
* xml-tdesc.c (struct tdesc_parsing_data): Rename current_union to
current_type. Add current_type_size and current_type_is_flags.
(tdesc_start_union): Clear the new fields.
(tdesc_start_struct, tdesc_start_flags): New.
(tdesc_start_field): Handle struct fields, including bitfields.
(field_attributes): Make type optional. Add start and end.
(union_children): Rename to struct_union_children.
(union_attributes): Rename to struct_union_attributes. Add optional
size.
(flags_attributes): New.
(feature_children): Add struct and flags.
* features/gdb-target.dtd: Add flags and struct to features.
Make field type optional. Add field start and end.
doc/
* gdb.texinfo (Types): Describe <struct> and <flags>.
testsuite/
* gdb.xml/extra-regs.xml: Add struct1, struct2, and flags
types. Add structreg, bitfields, and flags registers.
* gdb.xml/tdesc-regs.exp: Test structreg and bitfields
registers.