Kernel Module - GCC Requires memmove

Dimitry Andric dimitry at
Wed Jan 21 15:44:23 PST 2009

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

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