Re: [PATCH 5/5] ntdll: Implement RtlSetUserValueHeap.

[Zebediah Figura]

On 6/7/22 13:33, Rémi Bernon wrote:
> typedef struct
>   {
> - SIZE_T __pad[sizeof(SIZE_T) / sizeof(DWORD)];
>  struct list           entry;      /* entry in heap large blocks list */
>  SIZE_T                data_size;  /* size of user data */
>  SIZE_T                block_size; /* total size of virtual memory block */
> - DWORD                 pad[2];     /* padding to ensure 16-byte alignment of data */
> - void                 *user_value;
>  DWORD                 size;       /* fields for compatibility with normal arenas */
>  DWORD                 magic;      /* these must remain at the end of the structure */
> } ARENA_LARGE;

Doesn't this end up wasting space on 64 bits? I.e. the structure is 
already aligned to a multiple of 16 bytes without any padding.

(Also, somewhat out of curiosity, why move the member?)