Re: Does malloc() have to zero the block?

[Ralph Hempel <rhempel@...>]

Roberto Ierusalimschy wrote:
> > Does Lua ever realloc() or malloc() 0 bytes?
>
> Frequently.
>
>
> > What are the expected semantics of:
> >
> > 1. realloc() an existing block to a size of 0 bytes?
>
> Free the block. (Assuming 'realloc' is Lua allocation function.)

Which is done for us in l_alloc() automatically. The system
specific implementation realloc() is never called in that case.

> > When nsize is zero, the allocator must return NULL; if osize is not
> > zero, it should free the block pointed to by ptr.
>
>
> > 2. realloc() a new block to a size of 0 bytes?
>
> no op (unlike C realloc).

Hmmmm - this should never happen since l_alloc handles that case for
us :-)

Thanks. It's always nice to get one's answers to questions answered
straight from the horse's mouth!

Cheers, Ralph