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Subject: Re: [Qemu-devel] [PATCH] Introduce QEMU_NEW()
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org

On 07/25/2011 01:06 PM, Stefan Hajnoczi wrote:
> >    char *qemu_strndup(const char *str, size_t size);
> >
> >  +#define QEMU_NEW(type) ((type *)(qemu_malloc(sizeof(type))))
> >  +#define QEMU_NEWZ(type) ((type *)(qemu_mallocz(sizeof(type))))
>
> Does this mean we need to duplicate the type name for each allocation?
>
> struct foo *f;
>
> ...
> f = qemu_malloc(sizeof(*f));
>
> Becomes:
>
> struct foo *f;
>
> ...
> f = QEMU_NEW(struct foo);
>
> If you ever change the name of the type you have to search-replace
> these instances.  The idomatic C way works well, I don't see a reason
> to use QEMU_NEW().

It works as long as you don't make any mistakes:

   f = qemu_malloc(sizeof(*g));
   f = qemu_malloc(sizeof(f));

qemu_malloc() returns a void pointer, these are poisonous.

-- 
error compiling committee.c: too many arguments to function