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Date: Thu, 22 Jan 2009 00:44:23 +0100
From: Dimitry Andric <dimitry@andric.com>
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To: Andrew Brampton <brampton+freebsd-hackers@gmail.com>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Kernel Module - GCC Requires memmove
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On 2009-01-21 13:12, Andrew Brampton wrote:
> The .ii file (post-processed source) did NOT mention memmove at all.
> So I found it very odd that an undefined symbol existed in the object
> file.  So then I looked in the .s file (asm), and it was clearing
> making a single call to memmove.

This can (amongst others) occur if you assign structs, e.g.:

int test(void)
{
	struct foo {
		char bar[100];
	} a, b;

	b = a;
}

Compile this with gcc -O0 -S, and you'll see it generates a call to
memcpy().