RE: [PATCH] maple_tree: Use correct variable type in sizeof

[David Laight]

From: Peng Zhang
> Sent: 10 April 2023 11:09
> 
> 在 2023/4/10 17:46, Gang Li 写道:
> > On 2023/4/10 17:14, Peng Zhang wrote:
> >> The original code is:
> >>     memset(pivs + tmp, 0, sizeof(unsigned long *) * (max_p - tmp));
> >>
> >> The type of variable pointed to by pivs is unsigned long, but the type
> >> used in sizeof is a pointer type. Change it to unsigned long.
> >>
> >
> > Maybe add a fix tag?
> >
> > Fixes: 54a611b60590 ("Maple Tree: add new data structure")
> 
> Maybe sizeof(void *) is equal to sizeof(unsigned long)
> in most architectures, so I don't know if it counts as a fix.

Might be worth adding; "Fortunately the sizes are the same."

> >>             if (tmp < max_p)
> >>               memset(pivs + tmp, 0,
> >> -                   sizeof(unsigned long *) * (max_p - tmp));
> >> +                   sizeof(unsigned long) * (max_p - tmp));
	sizeof (*pivs)

> >>             if (tmp < mt_slots[mt])
> >>               memset(slots + tmp, 0, sizeof(void *) * (max_s - tmp));
	and sizeof (*slots)


	David

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