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Date: Tue, 24 Jan 2012 13:45:10 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Cyrill Gorcunov <gorcunov@gmail.com>,
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Subject: Re: [patch 2/4] [RFC] syscalls, x86: Add __NR_kcmp syscall v4
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On Tue, 24 Jan 2012 13:22:22 -0800
Andrew Morton <akpm@linux-foundation.org> wrote:

> static int kcmp_task_pointers(void *task1, void *task2, size_t field_offset,
> 				enum you_forgot_to_name_the_enum type)
> {
> 	void **field1 = t1 + field_offset;	/* points to a pointer in the task_struct */
> 	void **field2 = t1 + field_offset;

On reflection, this was being too cute.  It would be better to make the
function type-safer and just put up with the local typecasts:

static int kcmp_task_pointers(struct task_struct *task1,
			struct task_struct *task2, size_t field_offset,
			enum you_forgot_to_name_the_enum type)
{
	void **field1 = (void *)t1 + field_offset;
	void **field2 = (void *)t2 + field_offset;