structs: lazily allocate special slots array.

A type which we never ask for a special slot need not
waste space the array.

* struct.c (struct struct_type): Change spslot from array to
pointer.
(make_struct_type): Initialize spslot pointer to zero.
(struct_type_destroy): Free the dynamic array.
(invalidate_special_slot_nonexistence): Do nothing if the
spslot pointer is null.
(get_special_static_slot): Dynamically allocate the array
if the spslot pointer is null, and update that pointer,
before doing anything else. The parameter signature changes;
instead of a pointer to an element of the stslot array, we
pass the index.
(get_equal_method): Pass the index of the equal method special
slot, rather than the address of the array entry.

0 files changed, 0 insertions, 0 deletions