* gdbtypes.h (struct builtin_type): Add internal_fn member.
* gdbtypes.c (gdbtypes_post_init): Initialize it.
* value.c (internal_fn_type): Remove.
(_initialize_values): Do not initialize it.
* value.c (struct internalvar): Add enum internalvar_kind type and
kind member. Restructure union internalvar_data type. Remove type,
canonical, and make_value members.
(init_if_undefined_command): Update for data structure changes.
(create_internalvar): Likewise.
(create_internalvar_type_lazy): Likewise.
(get_internalvar_integer): Likewise.
(get_internalvar_function): Likewise.
(set_internalvar_component): Likewise.
(set_internalvar): Likewise.
(set_internalvar_integer): Likewise.
(set_internalvar_function): Likewise.
(clear_internalvar): Likewise.
(add_internal_function): Likewise.
(preserve_one_internalvar): New function.
(preserve_values): Call it.
* value.h (value_of_internalvar): Add GDBARCH parameter.
(internalvar_make_value): Likewise.
* value.c (value_of_internalvar): Add GDBARCH parameter. Pass it to
make_value callback. Use it to generate per-architecture result value
types for internal variables with no pre-defined type. Update for data
structure changes.
(show_convenience): Pass architecture to value_of_internalvar.
* eval.c (evaluate_subexp_standard): Likewise.
* infrun.c (siginfo_make_value): Add GDBARCH parameter. Use it
instead of current frame architecture. Return per-architecture type.
* value.h (set_internalvar_string): Add prototype.
* value.c (set_internalvar_string): New function.
* tracepoint.c (set_traceframe_context): Use it.