Fields
- free_list: *void
- block_count: u32
- size_class: u32
- free_list_limit: u32
- used_count: u32
- free_list_deferred: *void
- list_size: u32
- block_size: u32
- flags: enum_flags u32 { MASTER :: 1; SUBSPAN :: 2; ALIGNED_BLOCKS :: 4; UNMAPPED_MASTER :: 8; }
- span_count: u32
- total_spans: u32
- offset_from_master: u32
- remaining_spans: s32
- align_offset: u32
- heap: *Heap
- next: *Span
- prev: *Span